Post on 03-Dec-2014
GRUNDFOS SP ENGINEERING MANUAL
1 Introduction
Water supply2.1 Resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.2 Groundwater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.2.1 Groundwaterwells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.2.2 Riverbankfiltration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.2.3 Groundwaterrequirement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102.2.4 Requiredraw/wellwaterandwatertreatmentcapacity.......................................... 112.2.5 Wellyieldandoperationalefficiency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.3 Surfacewater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142.3.1 Fromfreshwatersources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142.3.2 Fromtheseaandsaltwatersources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Applications3.1 Freshwatersupply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173.2 Dewatering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.2.1 Mining. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.3 Horizontalapplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.4 Air/gasinwater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.5 Corrosivewater(seawater) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223.6 Hotwaterandgeothermalwater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233.7 Boostermodules. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Pumps4.1 Pumpprinciple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274.2 Wearparts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284.3 Pumpselection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284.4 Pumpcurvesandtolerances. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Motors and controls5.1 Motortypes,generaldescription . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335.2 Motorcablesandjoints,referencetodropcables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355.3 Motorprotectiondevices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365.4 Reducingthelocked-rotorcurrent. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365.4.1 Direct-on-line–DOL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375.4.2 Star-delta–SD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385.4.3 Autotransformer–AT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395.4.4 Primaryresistor-typestarter,RR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395.4.5 Softstarter–SS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395.4.6 Frequencyconverters(variablespeeddrive) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405.5 Operationwithfrequencyconverter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415.6 CUEvariblespeeddriveforSPpumps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6 Power supply6.1 Powergeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476.2 Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476.2.1 Voltageunbalance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476.2.2 Overvoltageandundervoltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476.3 Frequency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 486.4 Variablefrequencydrives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 486.5 Gridconnection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 496.6 Currentasymmetry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
7 Installation & operation7.1 Wellsandwellconditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557.2 Pumpsetting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567.3 Pumpandmotorselection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567.3.1 Thedutypoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Contents
7.3.2 Welldiameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577.3.3 Wellyield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577.3.4 Pumpefficiency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577.3.5 Watertemperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 607.3.6 Deratingofsubmersiblemotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 607.3.7 Protectionagainstboiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617.3.8 Sleevecooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617.4 Riserpipeselection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 627.5 Cableselectionandsizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 637.6 Handling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657.6.1 Pump/motorassembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657.6.2 Cablesplice/Connectionofmotorcableanddropcable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657.6.3 Riserpipeconnections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 667.7 Pumpsinparalleloperation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 667.8 Pumpsinseriesoperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 667.9 No.ofstart/stops. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 677.10 Pumpstartup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 677.11 VFDoperation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 677.12 Generatoroperation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
8 Communication8.1 Generalintroduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 718.2 CommunicationsandNetworkingTechnology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 718.3 SCADAsystems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728.3.1 SCADAmainparts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728.3.2 SCADAfunctions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728.3.3 Web-hostedSCADA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 738.4 Networkingbasics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 748.4.1 Networkingtopology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 748.4.2 Communicationsprotocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 758.4.3 Functionalprofile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 758.4.4 Thefieldbus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 758.5 GENIbus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768.5.1 Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768.5.2 Technicaldescription. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768.5.3 Cablingguidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 778.6 GrundfosGENIbusproductsforSPApplications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
9 Troubleshooting9 Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
10 Accessories10.1 Coolingsleeves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8310.2 Corrosionprotectioninseawater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8310.2.1 Cathodicprotection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8310.2.2 Galvaniccathodicprotectionsystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8310.2.3 Impressedcurrentcathodicprotectionsystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8410.3 Dropcables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8410.4 Cablejoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8510.5 Riserpipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
11 Additional information11 Additionalinformation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
1 Index12 index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
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Introduction
1.Introduction
Serving our common interests
ThisengineeringmanualhasbeencreatedwithaspecificfocusononeofGrundfos’mostrecognisableandpopularpumps:theSP.Whenitwascreatedinthelate1960’s,thisbreakthroughproductsetnewstandardswithindurability,efficiency,andconstructioninthin-platestainlesssteel.Thenumerousproducttypes,sizes,andconfigurationpossibilitiesavailabletodayserveasatestamenttotheinnovativenatureoftheoriginalSPpumps.
WorkingwithSPpumpsonadailybasisoftengivesrisetolotsofdifferentquestions.Wehavecreatedthisen-gineeringmanualtohelpyouquicklyandeasilyfindtheanswerstoanumberofthesequestions.WeserveourcommoninterestsofprovidingthebestpossibleSPsolutionsandserviceforallcustomers.
Pleasenotethatthisengineeringmanualisasupplementtoandnotareplacementforproductdatabookletsand installationmanuals.Thenewesteditionsof thesepublicationsarealways themostvalidandmustbeadheredto.
Wehavetakenconsiderabletimeandcaretomakethepresentationasconvenientandeasytouseaspossible.Werealise,however,thatthereisalwaysroomforimprovement,andinviteyoutocomment.PleasecontactyourlocalGrundfosrepresentativeiftherearesubjectsyouwouldliketoseecoveredinfutureeditions.
WesincerelyhopethatyoufindthismanualausefulreferencetoolinyourworkwithSPpumps.
KenthH.NielsenGlobalprogramDirector,GrundfosManagementA/S
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.Water Supply
Water supply
.1 ResourcesThe amount of water in the world is constant. It ischangingposition,quality,phase,etc.,but it iscon-stant.Seawateraccountsforapprox.97.5%ofallwa-ter.Freshwateraccountsfortheremaining2.5%.Two-thirdsof the freshwater isboundasglaciers,polarice,andsnowcover.Theremaining,lessthan1%ofallwaterintheworld,issomehowavailableindifferentsourcesformankindtouse.
Thesesourcesare:• groundwater,shallowordeepundergroundaqui-
fersofwater• surfacewater,fromriversorlakes.Incasenofreshwaterisavailable,seawaterorcon-taminatedwateristreatedandusedasfreshwater.
. GroundwaterGroundwater is typically between 25 and 10,000yearsold.Beforeitreachestheaquifer,ithasbeenfil-teredandexposedtobiologicaltreatmentonitswaythroughthevariouslayersoftheground.Groundwa-ter is therefore usually of high quality and requireslittleornotreatmentbeforeitisconsumed.
..1 Groundwater wellsIrrigation and water supply systems serving up to500,000consumersandtheadjacent industriesareideallysuppliedbygroundwater.Pollution-freeaqui-ferslargerthan600km2arenormal.75to150well-in-takesspreadonthedifferentaquiferswillprovidethemost environmentally-friendly, safest and reliablewater sources. For waterworks serving more than 1millionconsumers,anadditionalsourcesuchasriv-erbankfiltration, riverdams,ordesalinationshouldbeconsidered.
The individual wells are to be extended into oldergroundwateratpollution-freedepthswhenextract-ingfordrinkingwater.Irrigationwellscaneasilyusewaterfromtheupperaquifer,thesecondaryaquifer,withslightlypollutedwaterquality.Thegroundwa-ter level will vary over the seasons, but is to be re-spectedontheyearlybasis,asthemaximumremov-ablequantityissimilartowhatiscreatedeveryyear.
If groundwater levels are permanently lowered, awatersupplydisasterwithanincreasingsalinityandotherundesiredsubstancescanbeexpected.
Well head
Pump
Pump inlet
Gravel packing
Well screen
Submersible motor
Redox layer
Casing sealedat layers of clay
Fig. 1 Groundwater well with submersible pump
.. Riverbank filtrationInriverbankfiltrationwells,thewellisplacednearbyariver.Usingthismethod,theriverwaterisfilteredthrough the ground.This process is a natural addi-tiontoadirectintakeplantneedingcapacityenlarge-ment.The easy-to-clean, pre-filtered water requireslessfinaltreatmentandextractswaterfromtheaq-uiferwhentheriverlevelrunslow.
After every wet period with high river water levels,themud/dung/sedimentsoftheriverbedarewasheddownstreamandpartlyreplacedbynewsediments.Thisnaturalprocessprovidesperfectconditionsfora90%reductionofhuman-inducedenzymes,viruses,bacteria,pathogens,andsoon.Eachwetperiodwithhighriverwater levelsalsofillstheaquifersaroundtheriverwithwater,whereitisstoredandreadyfor
10 11
Water supplyWater supply
feedingtheriverbankwellswhentheriverwaterlev-elrunslowindryseason.Thestorageofriverwaterinaquiferscauseslesswaterstressontheriverduringdryseasons.
Riverbankwellscanbeconstructedlikegroundwaterwells,orfrom7-8mverticalcasingsdugdownunderthe riverbed. They can be supplemented with 8-12horizontal injected steel screens or filters for sedi-ment-freewaterintake.
Fig. 2 Riverside well installations
Fig. 3 Riverbank filtration Bacteria, pathogens, etc. are trapped by the sediments.
.. Groundwater requirementThebasisfordeterminingthegroundwaterrequire-mentfromthewellfieldsistoevaluatetherelation-shipbetweenthewaterstoragevolumeandthefin-ished water production capacity compared to peakanddailyconsumption.
Tofindthepeakhourlyconsumption,pleaserefertotheMPC-BoostersectionofGrundfosWinCAPS/Web-CAPSorfigures4and5.
Pump-out requirementWaterisusedbymanydifferenttypesofconsumers,eachwithaspecificconsumptionpattern.Therearemany methods of calculating the maximum waterrequirement,bothmanualandcomputerisedones.
Thetablebelowcanbeusedforroughcalculationofthewaterrequirementfor:• officebuildings• residentialbuildingsincl.blocksofflats• departmentstores• hospitals• hotels.
Category UnitsAverange
m/h
Dwellings 2,000units 70
Officebuildings 2,000employees 30
Departmentstores 2,000employees 55
Hotels 1,000beds 110
Hospitals 1,000beds 80
Maximumpeakload(warmseason)
345
Factorsforcalculatingdailyconsumption:•Minimum100consumersconnected:Factor8•Minimum30consumersconnected:Factor4•Minimum10consumersconnected:Factor2.5The maximum daily consumption in the exampleabovewillbefactor8x345m3/h=2,760m3/day.
0 200 600 800 1000400
0
20
40
60
80
100
Hotels
Number of beds
Consumptionm3/h
Hospitals
Fig. 4 Peak water consumption
0 400 1200 1600 2000800
0
10
20
30
40
50
60
Departmentstores
Number of employees
Consumptionm3/h
Dwellings
Office buildings
Fig. 5 Peak water consumption
Peakhourlyconsumptionisstated,thiscanbecon-vertedintoassumeddailyconsumptionbyusingthefactors8/4/2.5.
.. Required raw/well water and water treatment capacity
The relationship between water storage and dailyconsumption illustrates thepercentageof thedailyconsumption that is present in storage. With thispercentage,followithorizontallyinfig.6tofindthenecessary percentage for raw-water requirement.Thedailyconsumptionmultipliedbythepercentageofraw-waterrequirementprovidesthenecessaryca-pacityfromthewellfields.
Ifatreatmentplanthasnocleanwatertankorwatertower, the raw-water and treatment capacity mustbe equal to the maximum hourly consumption, i.e.Qraw-water=345m3/hintheexample.
Ifthetreatmentplanthasaclean-watertankorawa-tertowercapacityof2,760m3,peak loadsituationscan be covered from the reservoir.This means thattheraw-waterpumpscanrunconstantlyaroundtheclockat2,760/24m3/h=115m3/h.
Theeffectivevolumeoftheclean-watertankand/orwatertowerandthemaximumcapacityofthetreat-ment plant are crucial for investment costs in con-nectionwithgroundwaterwells.
Intheexample,thereisaclean-watertankof1,600m3. This means that the water reservoir comprises1,600/2,760x100=58%ofthedailyconsumption.
At a maximum peak consumption of 345 m3/h andamaximumconsumptionof2,760m3/dayandwithaneffectiveclean-watertankvolumeof1,600m3,theraw-watercapacitymustbeatleast2,760x7.6/100=210m3/h.7.6istakenfromfig.2.Thiswillgiveamaxi-mumdutytimeoftheraw-waterpumpsof2,760/210=13hours/day.The210m3/haresplitupbetweenatleastthreetofourwells.Incaseoffewerwells,astandbyinstalla-tionmustbemade.
1 1
Water supplyWater supply
0 4 6 8 10 12 14 16 18 20 22 24 26 28 30 322
0
10
20
Minim
um 100 consum
ers connected
Minimum 100 consumers connected
Minimum 100 consumers connected
58%
7,6%30
60
50
40
80
100
90
70
Clean-water tank size as a percentage of daily consumption
34 %
%
Clean-water tank size as a percentageof daily consumption:
Raw-water requirement:
Raw-water requirement
Tank volume (m3)Daily consumption (m3/24h) x 100 = % tank capacity
x = % raw-water requirementDaily consumption (m3/24h)
100
Fig. 6 Raw-water and treatment capacity (m3/h) as a percentage af the daily consumption (m3/day)
.. Well yield and operational efficiency
Each well has specific capacity, consisting of m3/hfor each metre of drawdown of the pumping wa-ter level.Withyourraw-waterrequirement,youareabletoloadeachwelltoobtainthelowestaveragedrawdown.Thesmallerthedrawdown,thesmallerthetotalhead.Thesmallerthevoltagedropinpowercables,thebettertheoperationalefficiency.
• Overpumping will result in deep drawdown. Thisgivesroomforoxidation,resultingintheformationof ochre which may clog well screen and pump.Thismeansincreasedservicecostsforwellregen-erationandpossiblyreducedwelllife.
• Overpumpingmeansloweringofthewaterleveloftheaquiferwhichcanresult inchemicalchangesandprecipitationofheavymetals.Infiltrationofni-trateandpesticidesinthewatermayoccur,result-inginincreasedexpensesforwatertreatment.
Themostcommoncauseofoverpumpingofawelloraquifer is increasedwaterconsumption.This iscov-eredbyincreasedpumpcapacityorlongerdutytimeof the groundwater pumps without increasing thecatchmentareaorthenumberofwells.
Aquifer load When pumping at constant capacity for severalhours,thedynamicwaterlevelinthewellshouldre-mainfairlyconstant.Ifthelevelisloweredconsider-ably,thismeansthattheamountofpumpedwaterexceedstheinflux.Iftheleveldropsfromyeartoyear,thequantityofpumpedwatershouldbereducedandwaterfromotheraquifersshouldbeutilised.
Well loadDuringtestpumping,theamountofpumpedwateris increased at fixed intervals which will result in alowering of the dynamic water level. If the draw-downisplottedagainstincreasedpumping,aroughparabolawillresult.
Linear drawdown at moderate flowsAt moderate flows, this means that typically an in-creasedamountofwaterof1m3/hwillresultinanal-mostlinearincreaseinthedrawdownof10cm/m3.
Anincreasefrom10to20m3/hwillconsequentlyre-sultinaloweringofthewaterlevelofapprox.1m.Anincreasefrom10to30m3/hwillgivealoweringofthewaterlevelofapprox.2m.
Atmoderateflows,thedrawdowncurvewillbecloseto linearas the increaseddrawdown isduetoflowresistanceinscreensetting.
Parabolic drawdown at large flowsAtincreasinglylargeflows,aprogressivelyincreasingfrictionalresistanceinscreensettingandaquiferwillgive a parabolic drawdown curve of the second de-gree.Thismeansaprogressivelyfallingwaterlevelinthewellwithincreasedpumping.
An increase from 80 to 90 m3/h will give an addi-tionaldrawdownofapprox.5m;from80to100m3/happrox.11m,i.e.muchmorethanatmoderateflows.Themosteconomicwellloadoccursataflowwherethedrawdowncurvegoesfromlineartoprogressive.
If the well yield is not sufficient to meet the waterrequirement, even by prolonged operation, the fol-lowingshouldbedone:• Haveaspecialistlookattheproblem.• Haveasupplementarywelldrilled.
Pleasenotethatrulesandregulationsmayvaryfromcountrytocountry.
0 10 60 10090807050403020
40
10
20
30
50
m/h
Static water level
Gradient: 10 cm/m3/h
OverpumpingAcceptable well load
55
Increasing gradient
Fig. 7 Dynamic water-level variations by test pumping
1 1
Water supplyWater supply
. Surface water
..1 From freshwater sourcesSurface water is usually taken from lakes or rivers.Unlikegroundwater, it isnotprotectedfromnatureor human activities, and treatment is therefore al-waysnecessary.Surfacewater levelandqualitywillvaryovertheseasons.Forexample,afterheavyrain-fall,orsnowmelt,lotsofsolidsandsandarewasheddownstream.
Thesesharpandabrassivemineralsaswellasbiode-gradablematerialsaretobesettledorscreenedoffbeforepumpintaketoavoidnegativeeffectsonthefinal water treatment process. Submersible pumpsareidealfortheseapplicationswithperiodicuncon-trollably high water levels. Note that power cablesandelectricequipmentmustbeelevatedtoperma-nentlydrylocations.
Fig. 8 Settling tank principle
For more permanent installations, indirect riversideinfiltrationviasandorgravelbankfillingsto intakecasings or riverbank wells are recommended. Thisnatural filtering improves the water quality andsaves up to 20% on power consumption, chemicalsandtestingatfinaltreatment.
Usingdirectwaterintakeandstandardconventionalwatertreatmentwillonlyresultinamicroscopicdi-verse biodynamic-balanced fauna entering the ac-companying pipework and tank system. The faunacan range from single-celled organisms to millime-tre-sizedpredators.Thisfaunamustbeeliminatedbydosinghighlevelsofchlorine.Directwaterintakeatatemperateclimatewillrequirechemicaloverdosingduringthecoldestseasonoftheyear,whenchemicalreactionshaveslowedtonearlyinactivity.
.. From sea and saltwater sourcesCoastalseawaterintakeshouldbeplacedwherethelowestsaltcontentisexpected.Inthecoastalsplash-ingzone,a lotofwaterevaporatesmakingthesaltconcentrationofremainingwatersgreaterthanout-sidethesplashingzone.Infact,itcanbeuptotwiceasgreat.
This makes it necessary to extend the seawater in-take up to hundreds of meters from the splashingzonetoobtainthe lowestsaltcontent.Thistypeofintake structure is generally beneficial when intakecapacityexceeds1,000m3/h.
For intake capacities lower than 1,000 m3/h, cor-rosion-safe beach wells and coastal bank filtrationwellsarerecommended.Theseinstallationscanpro-videsavingsofupto20%peryearoncostsrelatedtomaintenance,repair,powerconsumptionandchemi-calsatthedesalinationplant.
Coastalbankfiltrationwellsareconstructedlikeriv-erbankfiltrationwells,butinhighercorrosionclassestoresisttheimpactfromthepresentsalts.
16 17
.Applications
Applications
.1 Freshwater supplyThesupplyof freshwaterfordrinkingwater, irriga-tion and various industrial applications is the mostcommonapplicationforsubmersiblepumps.Pumpsofmanydifferentdesigns,andmadefrommanydif-ferentmaterialscanbeusedwithareasonablygoodresulthere.
GrundfosSPpumpsmadeofstainlesssteelEN1.4301/AISI304aretheobviouschoiceforthisapplication.Ifthewellismadecorrectlyandproducesclean,sand-freewater,thepumpcanlastformanyyears.
However, in some livestock watering and irrigationapplications,thewaterqualityissopoorthatpumpsmadeofstandardstainlesssteelmaterialdonotsur-vivevery long. InthesecasesapumpinEN1.4401/AISI316orEN1.4539/AISI904Lstainlesssteelcanbeused.
Estimates for a timeframe for carrying out severalactivitiesarefoundinthediagramsbelow.They in-clude:• therecommendedserviceperiodscausedbywear
andtear• theexpectedservicerepaircost• thelossofefficiencyintheserviceperiods.
Pleasenotethatthediagramsdonotreflectlossofef-ficiencycausedbycloggingfromsedimentorscale.Service intervals for submersible pumps
Submersiblepumpsaresubjecttowear just likeallotherpumps.Unfortunately,theirplacementunder-ground makes viewing this wear difficult. The dia-gramhereenablesyoutocalculatethefollowing:
· WhenshouldIservicemysubmersiblepump?· Howmuchefficiencyhasbeenlostsincethe last
service?· Howmuchwillarenovationcost(approximately)?
Anumberofthingsmustbedeterminedbeforehand.Theyinclude:· Watervelocityatthecomponentyouwishtotest· Theconditionsrelatedtopumpmaterialandthe
pumpingenvironment· Thepresenceorabsenceofsolidsandaggressive
carbondioxide.
18 19
ApplicationsApplications
. DewateringDewatering in connection with mining applicationsorconstructionsites isoftendonewithsubmersiblepumps. The water quality determines whether thepumpcanbeastandardEN1.4301(AISI304)pump,orifithastobestainlesssteelofahighergrade.
When reducing groundwater levels, the aquifer isexposedtooxygen,creatingrustandotheradhesivesolids.Theyarewashedoutandpenetrates thewellscreen,thenpassingontothepumpinlet.
Tomaintainpumpperformance,thedutypoint istobeselectedtotherightofthebestefficiencypoint.
Thehigherthevelocityinsidethepump,thelongerin-tervalsbetweenservicecanbe.Ahighvelocitypreventsthepumpfromcloggingupandlosingperformance.Inveryadhesivemixtures,itcanbebeneficialtoremovethenon-returnvalvefromthepumptoenhanceback-washofthepumpandpipesafterpumpstoppage.
..1 Mining Miningisatypicaldewateringapplication.However,thewaterqualityisveryoftenaggressiveinrelation
to the submersible pump, and high-grade stainlesssteelisrecommendable.Aspecialminingapplicationis leachmining,whereanaggressiveliquidisusedtodissolvethemineralstobemined.Thesearethenpumpedwiththeliquidtothesurfaceandreclaimed.
Onewayofdoingthisisdescribedinthefollowing:
1. Find the chloride corrosion potential (chlorideequivalent=ppmchloride–(0.5xppmacid)).
2. Withthischlorideequivalent,usefig.10tofindtheminimumpHvalueacceptable forEN1.4539 (AISI904L) stainless steel. If the illustration indicatesthatthereisahighcorrosionrisk,epoxy-coatingofthemotorisrequired.
3. Mostpowercablematerialsandjunctionkitsareunstableinacidicwaters.Ifpossible,usetheblueGrundfos TML motor cable in full length to thejunctionboxonthesurface.
4. Installthepumpcenteringdeviceonyourpumpormotor to ensure perfect cooling of the entire sur-face.
5. If corrosion occurs, install ion-exchange units tobringdownthechloridecontent,orinstallzincan-odesascathodicprotection.
200 mg salt/litre
Recommended service intervals for submersible pumpsVelocity at components
Motor coolingWater pipesValve strainersChamber bowlsImpellers
510152025
80%
100%
70%
60%
50%
40%
2
8
4
12
16
20
123456789m/s
Average efficiency loss during service period
Expe
cted
reno
vatio
n in
% o
f the
pric
e of
a n
ew p
ump
FreshwaterBrackish water
0.24
0.32
0.20
0.12
0.44
0.48
0.40
0.36
0.04
0.16
0.14
0.18
0.12
0.10
0.08
0.06
0.04
0.02
Curve A
Curve B
Curve C
Curve D
Curve E
Curve F
Wat
er c
onta
inin
g 10
mg/
l sol
ids
Sand
free
wat
er
0 mg/l (all materials)
Differentiation line for water qualities without aggressive carbon dioxide
Differentiation line for salinity
10 mg/l (cast iron only)
20 mg/l (cast iron only)
40 mg/l (cast iron only)
800 mg salt/litre
2,000 mg salt/litre
Material loss per 1,000 hours of operation in [mm]
0.28
0.16
0.08
1 2 3
4567
Serv
ice in
terv
als i
n 1,0
00 h
ours
Curve A:Material: Cast ironpH: 5Oxygen content: 7 ml/lTemperature: 30o CSolids content: 10 mg/l
Curve B:Material: Cast ironpH: 7Oxygen content: 2 ml/lTemperature: 10o CSolids content: 10 mg/l
Curve C:Material: stainless steel impeller coated with hard chromiumor bronze impeller with hard chromium shaftpH: 5-8Oxygen content: 0-10 ml/lTemperature: 0-30o CSolids content 10 mg/l
Curve D:Material: Cast ironpH: 5Oxygen content: 7 ml/lTemperature: 30o C
Curve E:Material: Cast ironpH: 7Oxygen content: 2 ml/lTemperature: 10o C
Curve F:Material: Bronze or stainless steel impeller pH: 5-8Oxygen content: 0-10 ml/lTemperature: 0-30oC
%
Fig. 9 Recommended service intervals for submersible pumps
Thechartbelowisusefulasaguidelinetodeterminetheserviceintervalsforsubmersiblepumps.Followthestepsbelow:1. Notepoint1onCurveA.Pumpmaterialandmedia
conditionsareasindicatedinthelegend.2. Drawaparallellinetotheright.Impellermaterial
loss isapprox.0.18mmper1,000hoursofopera-tion(point2).
3. Followtheparallel lineuntilyoureachthediffer-entiationlinethatcorrespondstoaggressiveCO2and component material. Note the conditions intheexample(point3).
4. Dropdirectlydown(90°).TheaggressiveCO2con-tent has increased the material loss to 0.25mm.Notethesalinitylevelofthewater(point4).Drawahorizontallinethroughthispoint;followittotheleftandreadtheresults.
5. Recommendedserviceintervalsforyourpump:Af-terevery6,000hoursofoperation(point5).
6. Lossofefficiency:Approx.18%(point6).7. Estimatedcostofrenovatingthepump:75%ofthe
priceofanewpump(point7).
0 500
0
1
2
3
4
5
6
7
8
pH
Corrosion due to chlorides on R-version pumps at 35°C
5,000 50,000 300,000
ppm Cl-Brine
100,00010,000 20,000
High corro
sion ris
k
Little or n
o corro
sion ris
k
Balti
c/M
edite
rran
ean
seaw
ater
Paci
fic/A
tlant
ic se
awat
er
30,0
00 -
Hig
hest
corr
osiv
e po
tent
ial (
seaw
ater
)
SeawaterBrackish waterFreshwater
River mouthor coastal
waterlowering
Seawater,marine
environment
Miningwaters
Fig. 10 Corrosion due to chlorides
0 1
ApplicationsApplications
. Horizontal applicationPumping water from a tank or reservoir is very oftendonewithastandardsubmersiblepump.Asubmersiblepumphasmanyadvantagescomparedtoadry-installedpumpsuchas:• Lownoiselevel:Thesubmersiblepumpisverysi-
lentanddoesnotdisturbanyneighbours.• Theftproof:Thepumpisinstalledatthebottomof
thetank/reservoir.• No shaft seal:This eliminates the risk of leakage
aboveground.
In horizontal installations, Grundfos always recom-mendsthatyouincludeaflowsleeveandbaffleplateatlowwaterlevels.
Fig. 11 Flow sleeve on horizontally installed pump
Fig. 12 Vortex baffle plate on horizontally-installed pump (seen from above)
Fig. 13 Vortex baffle plate on horizontally installed pump (cross-section)
Ifmorethanonesubmersiblepumpisinstalledinatank or reservoir the distance between the pumpsmust equal the overall diameter of the pump andmotorincludingcoolingsleeve.
Submersible pumps used for fountain applicationsareofteninstalledhorizontally.Becauseofitslowin-ertia, a submersible pump is able to start and stopvery fast. This makes it ideal for fountain applica-tions.Becauseofthehighstart/stopfrequency,itisrecommended to use canned motors only. Rewind-ablemotorsshouldneverbeusedinconnectionwithanextremenumberofstartsandstops.
Thelargenumberofstarts/stopsisalsohardonthecontactors, which have a limited lifetime. In ordertoprotectthemotorfromfailure inthecontactors,Grundfos recommends that you install the phase-failurerelaybetweentheoverloadrelayandthemo-tor.
Finally, it is important to size the pump and nozzletogether,sothepumpneveroperatesatmaximumflow,butalwaysasclosetothebestefficiencypointaspossible.
. Air/gas in waterIf air/gas is mixed in the pumped water, the pumpwillunderperform,andsometimesevenstoppump-ing.Air/gasgreatlydisturbsthehydraulicfunctionsof centrifugal pumps.To improve performance, thepumpmustbesubmergeddeeperintothewell,thusincreasingthepressure.
Ifthatisnotpossible,theproblemmaybeovercomeby installing a sleeve around the pump, below thepump inlet. The sleeve should extend upwards asfar as possible, but never above the dynamic waterlevel.
Fig. 14 Gas evacuation
Gas vacuum
Gas
Groundwater level
5-7 m
Water level in casing
Vacuum switchVacuum pump
Non-returnvalve
Vacuum gauge
Fig. 15 Vacuum wells
Vacuum wellsIfthewellwatercontainssomuchgasinsuspensionthatasleeveisinsufficienttomeetthewaterqualityrequirements,avacuummustbecreatedinthewellcasing.Thiscanbedonebyconnectingavacuum
pumptotheventpipewhenthecasingishermetical-lysealed.ThisrequiresthatthewellcasingisstrongenoughtowithstandthevacuumandthattheNPSHrequirementismet.
ApplicationsApplications
. Corrosive water (seawater)Submersiblepumpsareusedformanyseawaterap-plicationslikefishfarming,offshoreindustrialappli-cationsandwatersupplyforreverseosmosis-treatedwater.
SPpumpsareavailableindifferentmaterialsandcor-rosion classes depending on the application of thepumps.Thecombinationofsalinityandtemperatureisnotfavourabletostainlesssteel,andmustalwaysbetakenintoconsideration.A good way to compare the corrosion resistance ofstainless steel, is to compare its resistance againstpitting. The figure used as a comparison is called:‘PittingResistanceEquivalent’(PRE).Fig.16showsthemostcommonstainlesssteeltypesusedbyGrundfos.
PRE=(%Cr)+(3.3x%Mo)
Forcomparisontootherstainlesssteeltypes,whichcontainNitrogen(N)theformulalookslikebelow:
PREN=(%Cr)+(3.3x%Mo)+(16x%N)
In addition to temperature and salinity, the corro-siontemperatureisaffectedbythepresenceofothermetals,acidsandbiologocalactivity.Thisisalsoindi-catedinfig.16.
Thechartbelowcanbeusedfortheselectionofthepropergradeofsteel. 0 200 400 600 800 1000 1400 1600 1800 20001200
Corrosion diagramEN 1.4301, 1.4401 and 1.4539
Chloride [ppm]
Tem
pera
ture
[°C]
0
20
40
60
80
100
10
30
50
70
90
SPR 1.4539
SPN 1.4401
CRN 1.4401
SP 1.4301
Fig. 17 Corrosion diagram
0 2000 4000 6000 8000 16000 2000012000
Corrosion diagramEN 1.4301, 1.4401 and 1.4539
Chloride [ppm]
Tem
pera
ture
(°C)
0
20
40
60
80
100
10
30
50
70
90
SPR 1.4539
SPN 1.4401
CRN 1.4401
SP 1.4301
Fig. 18 Corrosion diagram
Theelastomercomponentsinthepumpmayalsobedamaged by poor water quality, for example if thewaterhasahighcontentofhydrocarbonsandmanychemicals.InsuchcasesthestandardelastomercanbereplacedbyFKMrubber.TheGrundfosSPEpumpsareparticularlydesignedtomeettheserequirements.Forallothermodels,thepumpscanbespecifiedanddeliveredonrequest.
.6 Hot water and geothermal waterGroundwaterclosetothesurfacewillbeclosetotheaverageannualairtemperatureintheregion.Goingdeeper, the temperature will increase 2 to 3 °C foreach100mofwelldepth,intheabsenceofgeother-malinfluence.
Ingeothermalareas,this increasemightbeashighas5to15°Cforeach100mofwelldepth.Goingdeepforwaterrequirestemperature-resistantelastomers,electricalcables,connectionsandmotors.
Hotgroundwaterisusedforgeneralheatingapplica-tions,andforleisureinmanyareas,especiallythosewithvolcanicactivity.
The motor liquid of your submersible motor has ahigherboilingpointtemperaturethanthewellwaterprevents the motor bearing lubrication from beingreducedduetothelowerviscosityoftheliquid.Themotormustbesubmergeddeepertoraisetheboil-ingtemperatureasthetablebelow.
TemperatureVapour
pressureKinematicviscosity
°C mWC mm2/s0 0.00611 1.7924 0.00813 1.568
10 0.01227 1.30720 0.02337 1.00430 0.04241 0.80140 0.07375 0.65850 0.12335 0.55460 0.19920 0.47570 0.31162 0.41380 0.47360 0.36590 0.70109 0.326
100 1.01325 0.294110 1.43266 0.268120 1.98543 0.246130 2.70132 0.228140 3.61379 0.212150 4.75997 0.199160 6.18065 0.188
35
30
25
20
15
10
5
0
Tem
pera
ture
of s
tand
ard
seaw
ater
(21,
000
ppm
Cl¯)
- °C
Full-developed pitting resistance equivalent in 60 days
Critical crevice temperature instagnant water
EN 1.4301/AISI 304
Critical temperature for permanent still-standing water
Corrosion resistance of seawater-submerged pumps
Pitting resistance
PRE = % Cr + 3.3 x % Mo = 7.5
PRE = % Cr + 3.3 x % Mo= 24.3
PRE = % Cr + 3.3 x % Mo= 33.5
PRE = % Cr + 3.3 x % Mo= 34.9
EN 1.4401/AISI 316 EN 1.4462/AISI 904L EN 4539/AISI 904L
Zink
ano
des
incr
ease
tem
p.ac
cept
ance
by
15°C
Cast
iron
and
mild
ste
el a
node
s in
crea
se te
mp.
acc
epta
nce
by 5
°C
Biol
ogic
al a
ctiv
ity d
ecre
ases
te
mp.
acc
epta
nce
by 5
°C
Chlo
rine,
sul
phur
ic a
cids
and
che
mic
als
decr
ease
tem
p. a
ccep
tanc
e by
8°C
Environmental impact
Fig. 16 Corrosion resistance
Gasinthewateristobeexpectedwherethereisgeo-thermalactivity.Toavoidreducedpumpcapacityinageothermal water installation where air is mixed in,Grundfos recommends to install the pump a mini-mumof50mbelowthedynamicwaterlevel.
.7 Booster modulesGrundfos pump types BM and BME are SP pumpsbuiltintoasleeve.Byconnectingeachunitinseries,averyhighpressurecanbeobtained.
Thepumpsareprimarilyusedforreverseosmosisap-plications,producingcleanwaterfrompollutedwa-terorseawater.
Grundfos booster modules are also used for watersupplyindistributionnetworkstoboostwaterpres-sureoverlongdistributionlines.Themainadvantag-escomparedtoconventionalboosterpumpsarethequietoperation,andthereisnoshaftsealthatmayleak.
Fig. 19 Grundfos BM
ApplicationsApplications
6 7
.Pumps
Pumps
.1 Pump principleTheSPpumpisacentrifugalpump,wherethepumpprincipleistotransformmechanicalenergyfromthemotortovelocityenergyinthepumpedmedium,andthereby creating a pressure difference in the mediabetweenthepumpinletandoutlet.
(3) Outlet
(4) Impeller
(7) Guide vane
(6) Seal ring
(1) Inlet
(5) Shaft
(2) Stage (Chamber)
Fig. 20 Submersible pump principle
The pump consists in principle of an inlet (1), anumber of pump stages (2) and a pump outlet (3).Eachpumpstagecreatesapressuredifference,andthemorepressureneeded,themorestagesneedtobeincluded.
Apumpstageincludesanimpeller(4)wheretheim-peller blades transfer energy to the water in termsofavelocityandpressure increase.Each impeller isfixedtothepumpshaft(5)bymeansofasplinecon-nectionorsplit-coneconnection.
Forsubmersiblepumps,therearetwogeneraldesigntypes:• radial• semi-axial.
The radial design is characterised by a large differ-encebetweentheimpellerinletandtheoutletdiam-eteroftheimpeller.Itissuitablewhereahighheadisrequired.
Thesemi-axialdesignismoresuitableforlargerflowpumps.
A seal ring (6) between the impeller inlet and thechamberensures thatanyback flow is limited.Thechamber includesaguidevane (7),which leadsthewatertothenextstage.Italsoconvertsthedynamicpressureintostaticpressure.
Inadditiontoguidingthewaterintothefirstimpel-lers,thepumpinletisalsotheinterconnectorforthemotor.FormostpumpsthedimensionsconformstotheNEMAstandardfor4”,6”and8”.Forlargerpumpsand motors there are various standards dependingonthesupplier.Thepumpinletmustbedesignedinordertodeliverthewatertothefirstimpellerinthebestpossiblewayandtherebyminimisethelossesasmuchaspossible.Forsomeradialdesignedimpellers,theinletalsoincludesaprimingscrew(fastenedonthepumpshaft)inordertosecurethewaterintakeandavoiddryrunningofthepump.
The pump outlet normally includes a non-returnvalve, which prevents back flow in the riser pipe,
8 9
PumpsPumps
whenthepumpisstopped.Severalbenefitsareob-tainedsuchas:• Energylossduetobackflushisavoided.• Acounterpressureisalwaysensured,whenstart-
ingupthepumpagain.Thisisessentialinordertomakecertainthatpumpperformanceremainsonthepumpcurve.
• Damageinthepumpduetowaterhammeringislimited.
• Contamination of the groundwater due to backflushislimited.
. Wear partsDependingonthepumpedmediaandthenumberofyearsapumphasbeeninoperation,aserviceinspec-tionofthepumpisrecommended.Thisincludesre-placingallwearpartsinthepump.Therecommend-edservicepartsare:• bearings,radial• valveseat• neckrings• sealring• upthrustring.
If extensive wear from sand has occurred in thepump,replacingthepumpshaftandimpellersmayalsobenecessary.
Renewingthewearpartsincaseofserviceisessen-tialformaintainingahighpumpefficiencyandalowoperatingcost.
For further service information, see the Grundfosserviceinstructions.
. Pump selectionSelectionofapumpstartswithestimatingtheflowandpressure.Thetotalheadisthesumofthefollow-ing• dynamicwatertable(1)• liftaboveground(2)• dischargepressure(3)• lossesinpipes,valveandbends(4)
Friction losses: 0 m
Flow (Q): 60 m3h
Head: 90 m
: 80 m
: 50 m Pipe length of riser pipe: 0 m
: 10 m
Pipe length of discharge pipe: 0 m
4
4
3
2
1
Fig. 21 Total head calculation
When estimating the flow demand, the well yieldmust also be taken into consideration. Informationregarding the well yield is available from the welldrillers test report, which is made during well de-velopment. If possible, the necessary flow must bereducedasmuchaspossible.Thiswillminimisethewatertabledrawdown,andreducetotalpowercon-sumptionintermsofkwh/m3.
. Pump curves and tolerancesAfterestimatingthenecessaryflowandhead,pumpselectioncanbeperformedbyusingGrundfosWin-CAPS/WebCAPS or the corresponding pump databooklet.Bothsourcescontainperformancecurves.
In addition to the pump head, the required powerconsumption is also available in the data booklet,wherethepumpsupplierdistinguishesbetweenthemotorshaftpoweroutputP1(printedonthemotornameplate)andthemotorinputpower,P1.P1isusedforsizingtheelectricalinstallations.
PleasenotethatP4isthehydrauliceffectproducedbythepump.
P2 : Motor shaft power (=P3)
P1 : Motor input power
P4 : Hydraulic effect
Fig. 22 Power definitions
Normallythepowerconsumptionisalsoshownasafunctionoftheflow.
0 10 20 30 40 50 60
0
Q [m3/h]
H [m]
0
10
20 20
30
40 40
50
60 60
70
8080
100
120
Eta[%]
0 10 20 30 40 50 60
0
Q [m3/h]
P [kW]
0
16 8
12 6
8 4
4 2
NPSH[m]
SP 60-8ISO 9906 Annex A
Pumped medium = any viscous fluid
Eta, pump
NPSH
QH
Eta, total
Shadedareas show acceptable tolerances
P1
P2
Figures 23 and 24 Pump performance parameters including tolerances
Inthedatabooklet,informationregardingpumpef-ficiencyisalsoavailable,anditcanbeshownasthepump-endefficiency(basedonP2)orasacompletepump efficiency including the motor (based on P1).Insomecases,losesinnon-returnvalvesarenotin-cludedintheefficiencyshown.Theefficiencycurvesare used for the selection of pump size, where thebestefficiencyareamatchestherequiredflow.Ifthecompletepumpefficiencyisnotshown,itcanbecal-culated by using the flow (Q), head (H) and powerinputP1:
etatotal = (Q x H x 9.81)/( P1 x 600)
The NPSH value stands for “Net Positive SuctionHead”andisameasureforrequiredinletpressure=minimumwaterlevelabovepumpinlet.
In general, the NPSH value will increase for bigger
Fig. 23
Fig. 24
0 1
PumpsPumps
flowsandiftherequiredinletpressureisnotmet,itwill result inevaporationof thewateranda riskofcavitationdamageinthepump.
Ingeneral, therearemanydifferent localstandardsfor tolerances on performance curves. Pump per-formance for Grundfos SP pumps is shown accord-ingto ISO9906,AnnexA.QHcurvesprinted inthedocumentation show the nominal curve. AccordingtoISO9906,AnnexA,powercurvesonlyhaveanup-pertolerance.Forefficiencycurves,onlylowertoler-ances are shown. Please see the example shown infig.23and24above.Thegeneralconditionsaccord-ing to ISO 9906 for the performance curves in thisillustrationare:• Themeasurementsaremadewithairlesswaterat
atemperatureof20°C.• Curvesapplytoakinematicviscosityof
1mm2/s.Whenpumpingliquidswithahigherdensity,ahighermotoroutputisrequired.
In addition to QH, Q-P, Q-eta curves, an axial loadcurveisnormallyalsoavailableonrequest.Thedownthrust load is created by the hydraulics and trans-ferred to the motor thrust bearing. The total axialloadiscalculatedbymultiplyingthesingle-stageval-uesbythenumberofstages.Itcanbeusedtocheckwhetherthecapacityofthemotorthrustbearingissufficient.
Fig. 25 Single-stage axial-load curve, SP 60
.Motors and controls
Motors and controls
.1 Motor types, general descriptionThischapterdealsexclusivelywithsubmersiblemo-tors,andcontrolsforsubmersiblemotors.Submers-iblemotorsarespecialbecausetheyaredesignedtorununderwater.Otherwise,theiroperatingprincipleisthesameasallotherelectricmotors.
Please note that all Grundfos 4”, 6”, and 8” motorsconformtoNEMAstandards.
Asubmersiblemotorconsistsofamotorbodyandamotorcable.Thecableisdetachableinaplugsystem.Thecableisdimensionedforsubmergeduseinordertominimisethespatialrequirementalongthepump.Themotorcableisconnectedtothedropcableabovethepumpbyuseofacableterminationkit.Thedropcableusedtoraiseandlowerthepump.
CannedInacannedmotor,thewindingsareenamelwire(likeinstandardsurfacemotors)hermeticallysealedfromthe surroundings and filled with embedding ma-terial in order to withhold the windings and at thesametimeincreaseheattransfer.Thesemotorshavea journal bearing system, consisting of upper andlowerradialbearingsaswellasupthrustanddown-thrustbearings.Thrustandjournalbearingsrunhy-drodynamicallyinthewater-basedmotorliquid.
Wetwound (rewindable)Wetwound motors have a special water resistancewire, and a watertight joint between the windingsand the motor cable.The joint is always inside themotor,andnoplugsystemisavailable.
Themotorliquidmainlyconsistsofcleanwater.Theliquid circulates around the entire motor, transfer-ringheatawayfromwindingsandrotorandlubricat-ingthebearingsystems.
Oil-filledAnoil-filledmotorisequippedwithanimpregnatedstandard surface motor winding. Transformer oil isfilledintothemotorandusedaslubricantandcool-ing.Theoilcanbemineralorvegetableoilwithhighinsulationresistance.Themotorcablespliceistypi-callymadeinsidethemotoras inawetwoundmo-
tors, fewhaveplugsystems.Oil-filledmotors incor-porateaball-bearingsystem.
Single-phase motorsThere are several versions of single phase motors.Theyallhavetheirdistinctiveadvantagesanddisad-vantages.Mosttypesneedacapacitorandsomeoth-eraccessories,which isbuilt intoastarterbox.Thestarterboxisdedicatedforstartingagivenmotoratspecificvoltageandfrequency.
Permanent-split capacitor (PSC) motors Simpleandreliable,PSCmotorshavearun-typeca-pacitorincludedinthecircuit.Thecapacitorsizeisacompromisebetweenaddingstartingtorqueanden-suringahighefficiencyduringoperation.Pros:Simple,low-cost,reliableandsilent.Cons:Lowlocked-rotortorqueandlowefficiency.
L
PSC
Switch
Overload
Capacitor
Lightningarrestor(optional)
Main
Start
N
PE
CSCR RSIR
Switch
Lightningarrestor
Overload
L
Main
Start
N
PE
L
Main
Tmac
Start
Bimetal
N
PE
Startcap.
Relais
Runcap.
Capacitor start Capacitor run1,1 - 3,7 kW
CSIR
L
Main
Start
N
PE
Startcap.
Relais
Capacitor start Induction run0,37 ... 0,75 kW
Fig. 26 PSC
Motors and controls Motors and controls
Capacitor-start/induction-run (CSIR) motor Thestart-upcapacitorbooststhetorqueduringstartup.Thenitisdisconnectedbyaswitch.TheCSIRmo-tortypeistypicallyusedforsmallerkWratings.Pros:Locked-rotortorque.Cons:Noisyoperation(truesingle-phase),relayneededtocutoutthestart-upcapacitor.
L
PSC
Switch
Overload
Capacitor
Lightningarrestor(optional)
Main
Start
N
PE
CSCR RSIR
Switch
Lightningarrestor
Overload
L
Main
Start
N
PE
L
Main
Tmac
Start
Bimetal
N
PE
Startcap.
Relais
Runcap.
Capacitor start Capacitor run1,1 - 3,7 kW
CSIR
L
Main
Start
N
PE
Startcap.
Relais
Capacitor start Induction run0,37 ... 0,75 kW
Capacitor-start/capacitor-run (CSCR) motors This motor type has both a starting capacitor tobooststartingtorque,andaruncapacitor(PSC).Thisensures a smooth operation and a good efficiency.Themotortypecombinestheadvantagesofbothoftheabovetypes.Pros:Goodstartingtorque,highefficiency.Cons:Priceofcontrolbox.
L
PSC
Switch
Overload
Capacitor
Lightningarrestor(optional)
Main
Start
N
PE
CSCR RSIR
Switch
Lightningarrestor
Overload
L
Main
Start
N
PE
L
Main
Tmac
Start
Bimetal
N
PE
Startcap.
Relais
Runcap.
Capacitor start Capacitor run1,1 - 3,7 kW
CSIR
L
Main
Start
N
PE
Startcap.
Relais
Capacitor start Induction run0,37 ... 0,75 kW
Resistance-start/induction-run (RSIR) motorThis motor has a relay built directly into the motorwinding. The relay disconnects the starting phasewhenthemotorisrunning.Pros:Noneedforcapacitors(nocontrolbox),easeofinstallation.Cons: Limited starting torque, limited kW ratings(onlythrough1.1kW).
L
PSC
Switch
Overload
Capacitor
Lightningarrestor(optional)
Main
Start
N
PE
CSCR RSIR
Switch
Lightningarrestor
Overload
L
Main
Start
N
PE
L
Main
Tmac
Start
Bimetal
N
PE
Startcap.
Relais
Runcap.
Capacitor start Capacitor run1,1 - 3,7 kW
CSIR
L
Main
Start
N
PE
Startcap.
Relais
Capacitor start Induction run0,37 ... 0,75 kW
Fig. 29 RSIR motor
Terminology; -wire and -wire motorsThe terminology is related to the number of wiresneeded in the installation excluding earth cable. 2-wiremotorsmustbesuppliedbythreeleads:phase,neutralendearth.3-wiremotorsmustbesuppliedbyfourleads:phase,neutral,pointbetweenstart-andrun-windinginmotor+earthcable.
-wire motors: • PSCmotorsacapacitorisbuiltintothemotor.• RSIR.
-wire motors:• PSCmotorsifthereisacapacitorinthestarterbox
ontheground.• CSIRmotors• CSCRmotors
Motor deratingMotor derating is where there are special require-ments to the motor, such as high water tempera-ture, voltage tolerances outside of acceptable in-terval,orvoltageunbalance.Allofthesesituationsstress the motor winding more than what it hasbeendesignedfor.
The simplest solution is to use an oversized motor,typically not more two output sizes above the re-quiredoutput.Theresultisanextendedlifetime,buttheefficiency isnotoptimal, since themotorneveroperatesatitsoptimaldutypoint.Thepowerfactorisnormallybelowduetothepartialloadonthecon-struction.
Abettersolutionistohaveamotorspeciallywoundin a larger stack length. Due to the increased sur-face, the electrical data and cooling capability areimproved.Thesemotorsaredesignedforhighertem-peratures,widervoltagetolerances,etc.Also,theef-ficiency of a standard motor is maintained or evenincreased.
. Motor cables and joints, reference to drop cables
Submersible pump installation are designed to beused with the submersible motor, the motor cableand the joint between motor cable and drop cableunderwater.Ifforanyreasonthemotorcableisnotfullysubmerged,thecurrent-carryingcapacitymustalwaysbechecked.Seechapter7.5aswell.Therefore,themotorcable,jointandsubmergedpartof the drop cable have a relative large surface areathat is incontactwith thepumped media. It is im-portanttochoosethecorrectmaterialforthegiveninstallation. You must also be aware of your localdrinkingwaterapprovalrequirements.
Fig. 27 Schematic diagram of a CSIR motor Fig. 28 Schematic diagram of a CSCR motor
6 7
Motors and controls Motors and controls
. Motor protection devices Thesametypeofmotor-protectivedevicesusedforstandard surface motors can be used for submers-iblemotors.Itisimportanttosecureandlimitshort-circuitingcurrentsandprotectagainstphase-failuresaswellasoverload.
Most single-phase motors have a built-in thermalprotector.Iftheprotectorisnotbuiltintothewind-ing, it must be incorporated in the starter box.Theprotectorsfeatureautomaticormanualreset.Ther-mal protectors are designed to match the motorwindingcharacteristics.
Pt100andPt1000arelinearresistors.Combinedwithastandardsensordevice,theycanindicatethetem-perature development over time. On canned-typemotors, the sensor device is placed in the staybolthole; on wet-wound versions, the sensor device isplacedinthemotorliquid.
PTCandNTCresistorsarerarelyusedinsubmersibleinstallations because they are not sufficiently fastandreliabletoprotectthesubmersiblemotor.
GrundfosoffersaspecialtemperaturesensingdevicecalledTempcon.ItisaNTC-resistorbuiltinnearthewinding,andsensesthetemperature.Thetempera-tureisconvertedintoahigh-frequencysignal,trans-mittedtothecontrolpanelbymeansofpower-linecommunication. From the control panel, the signalcanbepickedupbya signalconverter, transmittedtotheMP204controlpanelandindicatedasatem-peratureontheMP204controlpaneldisplay.MP204isaadvancedmotorprotectordesignedforthepro-tectionofthesubmersiblemotoragainstnetdistur-bances.
. Reducing the locked-rotor currentThe purpose of reducing the locked-rotor current istoprotectotherequipmentagainstpowersurgesinconnectionwithhighpowerloads.Thisalsoprotectsthe piping against excessive pressure surges.There
areseveralwaysofreducingtheimpactonthemains,howevernotallofthemarerelevanttopumps.Thissectioncoversseveraldifferentwaysofreducingthelocked-rotorcurrent,andinformationaboutrunningsubmersiblepumpswithfrequencyconverters.
Thefollowingappliestoradialandsemi-radialpumps,includingGrundfosSPpumps.Axialpumpsarehowevernotdealtwithhere.
Asthelocked-rotorcurrentofapumpmotorisoften4-7timesashighastheratedcurrent,therewillbeaconsiderablepeakloadofgridandmotorforashortperiod.Inordertoprotectthegrid,manycountrieshaveregulationsforreducingthelocked-rotorcurrent.NormallyitisgivenasamaximumloadinkWorinAmpsallowedtostartDirectonLine(DOL);Themaximumloadallowedvariesquitealotthroughouttheworld,soyoumustbecertainthatyouadheretoyourlocalregulations.Insomecases,onlyspecificmethodsforreducingthelocked-rotorcurrentareallowed.
Thefollowingtypesaredescribedinthefollowing:
DOL-Direct-on-lineSD-Star-deltaAF-AutotransformerRR–ResistorstarterSS-SoftstarterFC-FrequencyconverterBeforeachoiceismade,application,requirementsandlocalstandardsmustbeconsidered.
..1 Direct-on-line – DOLIn DOL starting, the motor is coupled directly to thegridbymeansofacontactororsimilar.Assumingallotheraspectstobethesame,DOLstartingwillalwaysgivethelowestgenerationofheatinthemotor,con-sequentlyprovidingthelongestlifespanofmotorsupto45kW.Abovethissize, themechanical impactonthemotorwillbesoconsiderablethatGrundfosrec-ommends current reduction. Furthermore, although
theDOLmotorstartergivesthehighestlocked-rotorcurrent,itwillcauseminimalgriddisturbance.
Lotsofsubmersiblepumpsuselongcables,however.Theselongcablesautomaticallytriggerareductionofthelocked-rotorcurrentduetothesimplephysicsin-volved,astheresistanceinthecablereducesthecur-rent.If,forexample,thecableislonganddesignedforavoltagedropof5%fullload(amps),areductionofthelocked-rotorcurrentwilloccurautomatically.Theexamplebelowillustratesthispoint.
Example:
0 1/10 second
x operating current
Power consumptionat startup
0
1
2
3
4
5
6
Time
Operatingcurrent
Sineperiods
Typically 3 to 5 periods
Fig. 30 Current flow by DOL starting
Type Reduced locked-rotor
current
Price Features in relation to
price
Space requirement
Customer friendly
Reliable Reduced pressure surge Energy sav-ings during operationMechanical Hydraulic
DOL No Low OK Low Yes Yes No No NoSD
Below kW above kW
NoYes
LowLow
LowOK
LowLow
YesYes
YesYes
No NoNo
NoNo
AF Yes Medium OK Medium Yes/No Yes Yes/No No NoRRSS Yes Medium OK Medium Yes/No Yes/No Yes No Yes/NoFC Yes High OK Medium/
highYes/No Yes/No Yes Yes/No Yes/No
8 9
Motors and controls Motors and controls
.. Star-delta – SDThemostcommonmethodforreducingthelocked-rotor current for motors in general is star-deltastarting. During start-up, the motor is connectedfor star operation. When the motor is running, itisswitchedovertodeltaconnection.Thishappensautomatically after a fixed period of time. Duringstart-up instarposition, thevoltageonmotorter-minals is reduced to 58 % of the nominal startingvoltage.Thisstartingmethodisverywellknowninthemarketandrelativelycheap,simpleandreliable,whichmakesitverypopular.
0
x operating current
Power consumptionat startup
Operatingcurrent
0
1
2
3
4
5
6
Time
Fig. 31 Current flow by SD starting
ForSPpumps,andingeneralforpumpswithalowmomentofinertia,SDstartingisnotrecommendeddue to the fact that speed is lost during switchingfromY/D.Asubmersiblepumpgoesfrom0to2.900rpmwithinthreecycles(0.06s)!Thisalsomeansthatthepumpstopsimmediatelywhenthecurrentisdis-connectedfromthemains.
When comparing the DOL and star-delta locked-ro-tor current, star-delta starting reduces the currentatthebeginning.Whenswitchingoverfromstartodelta,thepumpslowsconsiderably,almoststoppingcompletely.Afterwards,ithastostartdirectlyindelta(DOL).Thediagramshowsthatthereisnorealreduc-tionofthelocked-rotorcurrent.
Thingsaresomewhatdifferentforcentrifugalpumpswith a greater diameter and mass, as they conse-quentlyhaveahighermomentofinertia.Rememberthatstaroperationfortoolongmayresultinconsider-ablemotorheatingandareducedlifetimeasaresult.
SubmersibleinstallationswithSDstarterswilloftenbe more expensive than other similar installations.Twosupplycables(6leads)arerequiredforthemo-tor insteadofone(3 leads) inthenormalsituation.Themotormustalsofeaturetwosockets,makingittypically 5% more expensive than a traditional, sin-gle-socketmotor.
Fig. 32. Wye eonfiguration at start-up
Afterapre-determinedtime, thestarterelectricallyswitches the windings over to the Delta Configura-tion,showninfig.33.
Fig. 33. Delta Configuration motor
.. Autotransformer – ATIn this starting method, the voltage is reduced bymeans of autotransformers. This principle is alsocalledtheKorndorfmethod.
Fig. 34 Current flow by autotransformer starting
Whenthemotoristobestarted,itisfirstconnectedtoareducedvoltage,withfullvoltagefollowingafter-wards.Duringthisswitchover,partoftheautotrans-formerisconnectedasachokecoil.Thismeansthatthe motor will be connected to the grid the entiretime.Motorspeedwillnotbereduced.Thepowerconsumptionwhenstartingcanbeseenfromfig.34.
Autotransformer starters are relatively expensive,but very reliable.The locked-rotor current naturallydependsonthecharacteristicsofmotorandpump,andvariesconsiderablyfromtypetotype.
Never have the autotransformer in the circuit formorethan3seconds.
Fig. 35 Typical electrical diagram for an autotrans-former reduced voltage starter
.. Primary resistor-type starter, RRIn this starting method, the voltage is reduced bymeansofresistorsputinseriesoneachmotorphase.Thefunctionistoincreasetheresistanceduringthestartthus limitingthe locked-rotorcurrentflowing.Acorrectlydimensionedstarterwillreducethestart-ing voltage (on the terminals of the motor) to ap-proximately70%ofthelinevoltage.
Thestarteriscutoutbymeansofatimercontrollinga contactor which means that the reduced voltagewillonlybepresentforthepredefinedtimeandthatthemotorisenergizedtheentiretime.
Neverhaveresistorsconnectedformorethan3sec-onds,asitwillreducethestartingtorquewithconse-quentlyincreasedwinding.
Fig. 36. Typical electrical diagram for a primary resis-tor reduced voltage starter
.. Soft starter – SS Asoftstarterisanelectronicunitwhichreducesthevoltage and consequently the locked-rotor currentby means of phase-angle control. The electronicsunitconsistsofacontrolsection,wherethedifferentoperating and protective parameters are set, and apowerpartwithtriacs.
The locked-rotor current is typically reduced to 2-3timestheoperatingcurrent.
0 1
Motors and controls Motors and controls
0Max. 3 sec. Max. 3 sec.
0
55%
100%
Time
Operating
StopStart-up
Torque
Fig. 37 Recommended start-up and stop time, max. 3 sec.
Fig. 38 Current flow by soft starting
Otherthingsbeingthesame,thisalsogivesareducedstarting torque.The slow start may result in an in-creasedheatgenerationinthemotor,leadingtoare-ducedlifetime.Withshortacceleration/decelerationtimes(suchasthreeseconds),thisisofnopracticalimportance.ThesamegoesforSDandATstarting.
Grundfosthereforerecommendsfollowingtheaccel-eration/decelerationtimesstatedinthefigurewhenusingasoftstarter.Itshouldnotbenecessaryincon-nection with Grundfos pumps to raise the startingvoltage above 55%. However if a particularly highstartingtorqueisrequired,thestartingvoltagemaybeincreasedtoachievetherequiredtorque.
A soft starter will absorb a non-sinusoidal currentandgiverisetosomegridnoise.Inconnectionwithveryshortacceleration/decelerationtimes,thisisofno practical importance and does not conflict withregulationsconcerninggridnoise.
Anewseries/generationofsoftstartershasbeenin-troduced. They are equipped with a programmablestart ramp function for reducing the locked-rotorcurrent further,or for rampinghigh inertia loads. Ifsuch soft starters are used, please use ramp timesofmax. three seconds. In general,Grundfos recom-mends that you always install the soft starter witha bypass contactor, enabling the motor to run DOLduringoperation.Inthisway,wearandpowerlossisavoidedinthesoftstarterduringoperation.
Pleasenotethatiframpingdownisrequired,itmightnotbepossibletousethebypasscontactorsolutionforreducingthepowerconsumptionduringnormaloperation.
We recommend the use of frequency converters ifotherramptimesarerequired.
TemperaturereadoutofGrundfosmotorswithtem-perature transmitters is possible if the soft starterhasabypasscontactor.
Softstartersmayonlybeusedon3phasesubmers-iblemotors.Max.timeforreducedvoltageshallbelimitednottoexceed3seconds.
..6 Frequency converters (variable speed drive)
Frequencyconvertersaretheidealdevicetocontroltheperformanceofthepump,byadjustingthespeedofthemotor.Itisthereforealsoanidealstartertype,bothforreductionofthelocked-rotorcurrentandforreductionofpressuresurges.
Note:a lowfrequencyproducesslowimpellerrota-tion,reducingpumpperformance.
Fig. 39 Pump performance with different frequencies
0 3 secondsmin. 30 Hz
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
1.1
1.2
1.3
1.4
0.9
1,5
1,0
Typical start-up 30 seconds
Operatingcurrent
x operating current
Fig. 40 Current flow by frequency converter starting
Frequencyconvertersarethemostexpensiveoftheabove-mentionedstartingdevices,andwillprimarilybeusedinconnectionwithoperationatvariableper-formance.
There are several types of frequency converters onthe market, each having its own characteristics. Abriefoverviewispresentedhere:
• The simplest frequency converter is based on avoltage frequency curve.This converter is some-times called an U/f orV/f converter.They calcu-latetheactualoutputvoltagefromthefrequency,without taking the actual load into considera-tion.DifferentU/forV/fcurvescanbechosentooptimise for the actual application. Pumps willtypicallyusetheVariableTorquecurve.Thesefre-
quency converters are the cheapest on the mar-ket,andareoftenemployed.
• The next step is the Vector-Controlled frequencyconverter.Thisfrequencyconverterusesamodelofthemotor,andcalculatestheoutputvoltagebasedonseveralparametersincludingtheactualload.Thisgiveshigherperformanceincontrollingtheshaftofthemotor,suchasahigheraccuracyofmin-1,torque,etc. These drives are more expensive than the U/fbaseddrives,andaretypicallyusedforindustrialap-plications. However, they are also used in systemswhereinstabilitiesoftenoccur.Themoreprecisewayofcontrollingtheshaftnormallyeliminatestheprob-lemscausedbyaninstablepump,Thevector-control-leddrivesusuallyhaveahigherefficiency,oranauto-maticenergyoptimizerfunction.
Theoutputsectionofafrequencyconvertercanbemade intwodifferentways:eitherwithsixorwith12transistors.
Thiscanalsobereferredtoas6-pulseand12-pulseinverters. Six transistors are the most commonlyfound solution, as it is the cheapest and the sim-plestwayofcreatinganoutputstage.Toreducethestressonmotorinsulationandincreasethecontrolperformance, the 12-transistor output stage wasintroduced.12-transistoroperationistypicallycom-binedwithadvancedcontrolsthatarebasedonfluxmodelsofthemotor.Theadvantageofa12-transis-tor solution usually includes improved control atlowspeedsandlessstressonthemotor.A12-pulsefrequency converter lies in the expensive range offrequencyconverters.
Themainselectionfactorforcombiningfrequencyconverterandpumpisthefullloadampsincludingtheoverloadfactor.Thefrequencyconvertershouldbechosensoitcandelivertherequiredcurrentallthe time. For example, if the motor requires 9.7 A,chose a frequency converter with and output cur-rentat9.7Aorhigher.
. Operation with frequency converter
There are several things that should be consideredwhenusingfrequencyconverterstogetherwithsub-mersiblemotors.Someoftheconditionsforrunningsubmersible motors on frequency converters arefoundbelow.
1a.Thefrequencyconvertermusthavesomekindofoutput filter to limit voltage peaks (Upeak) andto reduce dU/dt (or dV/dt) which courses stresson the insolation of the submersible motor.Themaximumvoltage (Upeak) shouldbereducedtoalevel of less than 850V (except for the MS 402);dU/dt should also be limited in accordance withthefollowingtable.
Max peak voltage and max dU / dt for Grundfos submersibles
Motorseries Max.Upeakvoltage Max.dU/dt
MS402 650VPhase-Phase 2000V/micros.
MS4000 850VPhase-Phase 2000V/micros.
MS6/MS6000 850VPhase-Phase 2000V/micros.
MMS6/MMS6000 850VPhase-Ground 500V/micros.
MMS8000 850VPhase-Ground 500V/micros.
MMS10000 850VPhase-Ground 500V/micros.
MMS12000 850VPhase-Ground 500V/micros.
The typical output filters for frequency convert-ers are LC (also called sinus filters) or RC filters.Frequency converter suppliers can supply dataregarding Upeak and dU/dt for their different fre-quencyconverterseries.Pleaseseechapter5.6.
Normally,filtersarealsorequirediflongmotorca-bles are to be used together with the frequencyconverter.
TheUpeakanddU/dtvaluesshouldbemeasuredonthemotorterminals.
SeetableaboveforacceptablevaluesofdV/dt.
1b.Frequency converters are normally designed foruse in an industrial environment. If a frequencyconverterisusedinresidentialareas,itmightbenecessarytoaddsomekindofinputfiltertopre-
vent electrical disturbances from the frequencyconverterfromaffectingotherequipmentonthesame mains. Normally there are three differentlevelsoffilterstoselectamong:
• Nofilter(Onlyforindustrialusewherefilteringisdoneelsewhere)
• Filtersforindustrialapplications • Filtersfordomesticapplications. The version for domestic applications can be an
add-onfortheindustrialapplication,oritcanbeaseparateversion.
It is mandatory to fulfil the requirements in themanualsforthefrequencyconverterforkeepingthe CE mark on the product. If this is not doneproperlytheCEmarkingisnotallowed.
2. The flow rate past the motor must be at least0.15m/s.Themotormustbefittedwithacoolingsleeve if the pumping does not create sufficientflowpastthemotor.
3. Withcontrolofsubmersiblemotors inopensys-temswithhighstaticlift,thepowerconsumptionwill change only moderately. This means that areductionofthepumpperformancewillgive in-creasedgenerationofheatinthemotor.Areduc-tionof themotor lifetimemust thereforebeex-pected.Foroperationwithafrequencyconverter,Grundfos therefore always recommends using amotorwithsparecapacity,i.e.anindustrialmotororaderatedstandardmotor.
4. Themotorfrequency:min.:30Hzmax.:60Hz
5. TemperatureprotectionofGrundfossubmersiblemotors with frequency converter is possible formotorswithabuilt-inthermocontacts.Themotortemperaturecannotberead,buttheprotectionisthesame.Anadditionalcable isrequiredforthemotor, but as operation of submersible motorsbymeansoffrequencyconvertersisusuallyusedinconnectionwithtankapplication,thiswillnotcausedisturbancesoradditionalcosts.
If the points discussed above are met, the motor will have an acceptable lifetime.
Pleasenotethatexternalfrequencyconvertersresultinpowerlossandtransmitstransients,theywill:
• generatemoreheatinthemotorcomparedtodi-rectonlineoperation
• reducethemotorefficiency• increasethepowerconsumptionofthemotor.Because of this, an industrial motor should alwaysbeused,asithasbeenbuilttocompensateforthesedisadvantages.
Asfarastheoperatingeconomyisconcerned,thefol-lowingshouldbetakenintoconsideration:• Frequencycontrolofdeepwellsubmersiblepumps
will normally not result in improved operatingeconomywheninstalledinawell.
• Itdoes,however,reducetheneedforlargetanksandspaceforthese.
• Frequency control of raw-water pumps reducespressuresurgesinthepipesystemandvariationsof the water level in the well at pump start andstop.
Howeverwheresomekindofcontrolisneededsuchasconstantpressure,constantwellwaterlevel,orsimi-lar,theremightbedifferentlevelsofimprovementinusingfrequencyconverters.Afrequencyconverterin-cludessomelogicinputandoutput.Italsotypicallyin-cludesaPIDcontrolsection,forestablishingcontroloftheapplication. Inmanycasesadditionalequipmentcanbeomitted,andtheuseofthefrequencyconvert-erasastarterandasapartofthecontrolsystemwillimprovetheoveralleconomicperspective.
The PID controller is widely used in control applica-tions,andfrequencyconvertermanufacturesnormal-lygivessomehintsabouthowtooptimizetheuseofthisfeature.Please be aware of that an incorrectly programmedPIDcontrollercould leadtoan instableperformanceandexcessivepressureonthesystem.
Pleasenotethattheramp-uptimetoaminimumfre-quencyof30Hzmaynottakelongerthan3seconds.
.6 CUE variable speed drive for SP pumps
CUEisaGrundfosfrequencydrivewithalogicalin-terfaceforeasysetupandoperation.
WithaCUE, it ispossibletocontrolpumpperform-ance by changing the frequency.This allows you toprogram a smooth start up and stop of the pump.Thisminimisestheriskofdamagesonthepressurepipeandtheentirepressurepipingsystem.Italsore-ducesthestressfromwaterhammerwhileminimis-ingthecostsforvalvesandotherregulatingdevices.
Operation below 30 Hz is acceptable for no morethanthreeseconds.Above30Hz,thereisnolimita-tion regarding operation time.This must always beobservedhowever,bothduringramp-upandramp-downsequences.
Themax.frequencyis60Hz.
Motors and controls Motors and controls
Fig. 41 CUE family
Motors and controls Motors and controls
The set-up data for the CUE is always current, andnotkW,sincesubmersiblemotorsareoftendifferentfromnormmotors.
FunctionsThe CUE allows you to maintain the following pa-rameters:• Constantpressure• Constantlevel• Constantflowrate• Constanttemperature• Constantcurve.
Power cableAsubmersiblepumppowercableinascreenedver-sionisnotavailable.Normally, it isnotrequiredac-cordingtotheEMCregulationsduetothesubmergedinstallation.
Mains cableThis cable runs from the mains supply to the CUEunscreened. The cable between CUE and filter isscreened. The cable running from the filter to thepumpmotorisnormallyunscreened.Thetwoexam-plesillustratethesesetups.
Ifthecableisusedoutsidethewellinadryenviron-ment,ascreenedcablemaybeusedwithacablecon-nection to the submersible pump cable at the wellhead.fig.42belowshowshowacableselectioncanbeusedtogetherwithCUEandafilter.Inthesecondexample, the connection box is located at the wellhead.
Further information may be found in webCAPS onwww.grundfos.com.
Filter selectionFig.44belowshowshowtoselectthecorrectfilterfortheinstallation.
ThemaindifferencebetweendU/dtfiltersandsinewavefiltersis:Bothfiltersconsistofcoilsandcapacitors.ThecoilsandthecapacitorsaresmallinvalueinthedU/dtfil-terscomparedtothevaluesusedinsinewavefilters.
GrundfosoffersafullrangeoffilterstobeusedwithCUE.
Setting guidelines• Ramp(upanddown):maximum3seconds.This
istoensurethelubricationofjournalbearingstolimitwear,andpreventthewindingfrombecom-ingburntout.
• UsetemperaturemonitoringbyPT100(useofscreenedcablecanbeneeded).
• Heatkillsthemotor=>lowisolationresistance=>sensitivetovoltagepeaks.
• Motorrecommendations:–ForMS:usemotorswith10%extraingiven
dutypoint. –ForMMS:alwaysusemotorsthatarePE2–PA
wound.• RemembertouseaLCfilter.• Reducepeakstomax.800V.• GrundfosrecommendDanfossfrequencyinvert-
er,incombinationwithaLCfilter.• Cablesactasamplifiers=>measurepeaksatthe
motor.• Dimensionitwithrespectforthecurrentandnot
thepoweroutput.• Dimensionthecoolingprovisionforthestator
tubeatdutypointwithlowestflowrate.Theminimumflowm/salongthestatorhousingmustbeconsidered.
• Assurethatthepumpisusedwithintheintend-edrangeofthepumpcurve.
• FocusonthedischargepressureandsufficientNPSH,asvibrationswillkillthemotor.
CUE FilterMainsUnscreened cable screened cable Unscreened drop cable
CUE and Filter mounted close to well
M
CUE FilterMainsUnscreened cable
screened cable
Unscreened drop cable M
screened cable Connection
box*
* Both ends of the screened cable from the filter to the connection box must connected to earth
NO YES
How to chose a filter
Is the pump an SP/BM or BMB
Cable length<150m and
p> 11 kW
Use sine wave filter Use dU/dt filter
Fig. 42 Submersible pump without connection box
Fig. 43 Submersible pump with connection box and screened cable
Fig. 44 Setting guidelines
6 7
6.Power Supply
Power Supply
6.1 Power generation
Thefollowingwillonlyfocusonalternatingcurrent(AC)asthisistheprimarysourceofpowerforasyn-chronousmotors.
DistributionInorderforgeneratedpowertobeuseful,itmustbetransmitted from the generating plant to the areawhereconsumptiontakesplace.Thechallengeistohave sufficient amount of energy available at thetimeandplacewhereworkisdemanded.
Themostefficientwaytotransferenergyfromgen-erating plant to consumption places is to increasevoltage while reducing current.This is necessary inorder to minimize the energy loss as consequenceoftransmission.TheselossesarereferredtoasI2xRlosses,sincetheyareequaltothesquareofthecur-renttimestheresistanceofthepowerlines.Oncetheelectricalenergygetsneartheenduser,theutilitywillneedtostepdownthevoltagetothelevelneededbytheconsumingmachine.Eachtime,thevoltagelevelischanged,energyislost,eveninthemostefficienttransformers.
6. Voltage
6..1 Voltage unbalanceSubmersiblemotorsaredesignedtooperateonpow-erlineswithgivenvoltageandfrequency.
Voltageunbalancecanberegulatedattheregulatingboard of the transformer and/or the generator.Thevoltageunbalanceshallbekeptassmallaspossible,asitistheprimarysourceofcurrentunbalance.Thisleadstothecreationofadditionalheatinthemotor.
One possible cause of voltage unbalance is the un-equaldistributionofsinglephaseloads.Theseloadsvary over time. Voltage unbalance is subsequentlyvery difficult to avoid if the net contains high per-centageofsinglephaseconsumption.
Use of two single phase transformers in so called“open delta” connection is not recommended forthreephasesupply.
6.. Overvoltage and undervoltagePowerlinesareexpectedtodeliveraspecificvoltage.Near the low voltage transformer, there will oftenbeanovervoltageof3-5%.Whenthepowerlinesareloaded,avoltagedropwilloccurduetoohmicresist-anceinperiodsofpeakpowerconsumption.
Mostpowerlinesaredimensionedsothatundervolt-age of more than -10% will occur less than once ayearattheweakestpoint.Butmanyconsumersstillexperienceperiodsofconsiderablevoltagedrop.
Anymotorwillsufferifitdoesnotreceivethevoltagestampedonthenameplate.Ifthevoltagedrops,themotor torque will be reduced and the speed of theloadedmotorwillconsequentlybereduced,too.
Asaresultofthis,theefficiencyandinductionresist-anceofthemotorwilldrop.Thiswillmakethepowerconsumptionincrease,resultinginincreasedgenera-tionofheatinthemotor.
Whenafully-loadedcentrifugalpumpmotorreceives10% undervoltage, the power consumption will in-creasebyapprox.5%,andthemotortemperaturebyabout20%.Ifthistemperatureincreaseexceedsthemaximum temperature of the insulation materialaround the windings, these will be short-circuitedandthestatorwillbedestroyed.Inthesubmersiblemotor, the temperature of the motor liquid is veryimportantforthelubricationofthejournalbearings.Theloadcapacityasfunctionofthetemperaturecanbeseenonthediagrambelow.
Fig. 45 Diagram: Journal bearings load capacity as function of motor liquid temperature.
8 9
Power Supply
Thisiscriticalifthemotorisplacedinahotenviron-mentandisbadlycooled,orincaseofvoltageasym-metry, current asymmetry or voltage transients atthesametime.
Usually,anincreasedwindingtemperaturecausedbyundervoltagewill leadtofasteragingoftheinsula-tion,resultinginareducedlife.
Incaseofovervoltagefromthegrid,thepowercon-sumptionandheatgenerationinthemotorwindingswillincreaseaswell.
Fig. 46 Current variation as a function of over- and undervoltage on a 230 V motor.
Conclusion1. Forvoltagevariationsof+6/-10%oftheratedvalue,
measuredatthemotorterminals,normal lifecanbeexpectedwhenthepowerconsumptionisequalto or less than the rated current stamped on thenameplateandifthemotorcoolingissufficientandnotransientsorasymmetryoccur.
2. For short/periodic voltage variations exceeding+6/-10%oftheratedvalue,thereductioninlifewillbemoderateuntilundervoltage/overvoltagevaria-tionsaresoconsiderablethatthestatorwindingsareshort-circuited.
3. Withpermanentorlonglastingvoltagevariationsexceeding+6/-10%,themotorshouldbederatedora Grundfos oversize motor chosen in order to ob-tainacceptablelifeandefficiency.ControlofmotortemperatureisbyuseofGrundfosMP204electron-icallymotorprotectorisalwaysrecommended.
Itiscustomarytoderateastandardmotortoensurelonglifeifovervoltageorundervoltageofmorethan+6/-10%canbeexpectedatthemotorcableentry.Single-phase motors will often require capacitoradaptionwhenexposedtolowvoltagesupply.
6. FrequencyThefrequencyshouldalwaysbekeptatthenominalvalue.Ifthefrequencyishigher,thepumpmayover-loadthemotor.Ifthefrequencyislower,pumpper-formancewilldrop.
6. Variable frequency drivesInordertomakerationalelectricpowerdistributionutilitieshaveagreedtousesamefrequency.Thisen-abledirectconnectionofdifferentnetsundercondi-tionthatthefrequencyandsequenceofthisisthesame.The dominant frequencies used in the world todayare60Hzand50Hz.
Thefrequencydeterminesthespeedofanasynchro-nous motor. Unfortunately it is very difficult to cal-culateexactlythespeedofanasynchronousmotor.This is determined by the speed of a synchronousmotorminustheslip.
Slip is defined as the difference in speed betweenrotorandstatorfield.Theslip is theproductof theresulting torque – this means the greater the load,(torque)thegreatertheslip.Inotherwords,theslipofanasynchronousmotorisloaddependent.
Thesynchronousspeedcanbecalculatedbyuseoffollowingformula:
Ns = 10 x f P
Ns=thespeedoftherotatingmagneticfield.120=constant.f=frequency.P=numberofpoles.
Power Supply
Variablefrequencydrives(VFDs)areusedtocreatea “new” local net with a frequency different fromwhatthesupplycompany isproviding.Thisallowsthefrequencyandthemotor(andpump)speedtoberegulated.Modernfrequencydrivescanregulateinanintervalbetween0and400Hz(orevenmore).Pleaseremem-ber,asthespeedgoesuptheloadisalsoincreasingeventuallyleadingtoriskofoverloadingthemotorifnotdimensionedcorrectly.
Another important issue to remember is that thefrequencydrivemustnotbeusedtoboostvoltage.Whenyouregulatethevoltage,thefrequencymustremainconstant.
Practical example:Givennet=400V,50HzIn order to have bigger regulation area, you choosetodimensionthepumpsetfor60Hzoperation.Thisgivesrecommendedregulationareafrom30–60Hz.Hence you are not to boost voltage you have tochoose a motor suited for running at 400V, 60 Hz(practicallythiswillleadintochoosinga380V,60Hzmotorhencethisisastandard).
Filters:Variable frequency drives is based on a technologythat switches (chops) in and out the voltage. Thismeansthattheresultingoutputfromavariablefre-quency drive is only partly a sinusoidal curve. Theresult is generation of noise on primary as well assecondary side of the variable frequency drive. Theprimarysideisregulatedbyauthoritiesand/orutili-tiesanddemandsRFIfiltersolutions.Ontheoutputside,thechallengeisthelength,thetype,thesizeandhowthecablesareplacedintheinstallation.Longca-blesincreasetheriskofcreatinghighvoltagepeaksleadingtodeteriorationofthe insulationsystemofthesubmersiblemotor.
Grundfos recommends the use of LC filters on thesecondarysideofallvariablefrequencydrives.Ifthesupplier of aVFD with a given cable configurationwill issue assurance that Upeak for given motor isnotexceededatmotorterminalsthiscanbeaccept-ed.Seethetableonpage42.
Current:Pleasenotethatdimensioningofvariablefrequencydrives is done from the current value of the motor– and that a submersible motor has higher currentvaluesthansimilaroutputsurfacemotor.
6. Grid connectionBeforeconnectingtogrid,thecharacteristicsofthegrid shall be known: How is the quality of the net,whatkindofearthisusedandhowgoodisthesurgeandlightningprotection?
• Whatvoltagewillbesuppliedandwithwhattoler-ances?
• What frequency will be supplied and with whattolerances?
• Whatpowerisatdisposition?• Howoftencangriddisturbancesbeexpected?• Isanowntransformerforeseenorwillacommon
transformerbeused?Ifacommontransformerisused,askhowevenloadofthenetisassured(onlyapplicablefor3-phasemotors).
Thesupplyfromthegridtothemotorisnormallyre-ferredtoasthenetsupply.Netsupplyisthepowerlinehavingthevoltageformachineuses.Netqualitywedivideintosocalled“stiff”or“soft”net.
Agivengridvoltageistransformedintoappropriatenetvoltagebyuseofatransformer.Thecheapestwayoftransformingagivengridvolt-age into appropriate net voltage is done through asocalledautotransformer.Pleasenotethatthisisnotpossibleinallcountries.
Inordertoprotectthesubmersiblemotor,youneedadevicethatcanisolatethemotorfromthenet/gridsupply in case of problems. Grundfos recommendstheuseofelectronicmotorprotectordeviceMP204.
0 1
Power Supply
6.6 Current asymmetryLowcurrentasymmetrygivesthebestmotorefficien-cyandlongestlife.Itisthereforeimportanttohaveall phases loaded equally. Before measuring takesplace,itshouldbecheckedthatthedirectionofrota-tionofthepumpiscorrect, i.e.theonewhichgivesthe highest performance. The direction of rotationcan be changed by interchanging two phases. Thecurrent asymmetry should not exceed 5%. If thereisaMP204connected,10%willbeacceptable. It iscalculatedbymeansofthefollowingtwoformulas:
I (%) =Iphase max. – Iaverage
Iaverage( ) x 100 [%]
( )I (%) =Iphase – Iaverage min.
Iaverage
x 100 [%]
Themaximumvalueisusedasanexpressionofthecurrent asymmetry. The current must be measuredonallthreephasesasillustratedbelow.Thebestcon-nection is the one which gives the lowest currentasymmetry.Inordernottohavetochangethedirec-tionofrotationwhentheconnectionischanged,thephasesmustalwaysbemovedasillustrated.MP204makesitpossiblenotonlytoprotectagainsttoohighacurrentasymmetry,butalsotohavereadoutsoftheactualvaluesifusedwithanR100.Thismakesiteasytofindtheoptimalconnection.
Fig. 47 Optimal connection
ExampleSeethediagraminfig.45andthetablebelow.
Step1 Connection1UZ31AVX26AWY28A
Totally85A
Connection2Z30AX26AY29A
Totally85A
Connection3Z29AX27AY29A
Totally85A
Step2 =Totalcurrent3x3
=28.3A85+85+853x3
Averagecurrent:
Step3 Max.amps.differencefromaverage:Connection1=31-28.3=2.7AConnection2=28.3-26=2.3AConnection3=28.3-27=1.3A
Step4 %unbalance:Connection1=9.5%-nogoodConnection2=8.1%-nogoodConnection3=4.6%-ok
Step5 Ifthecurrentunbalanceisgreaterthan5%,thepowercompanyshouldbecontacted.Asanalternative,aderatedorindustrialmotorprotectedbyanMP204shouldbeused.Ontheremotecontrol,youwillbeabletoreadtheactualcurrentasymmetry.Acurrentunbalanceof5%correspondstoavoltageunbalanceof1-2%.
Evenasmallvoltageunbalancegivesalargecurrentunbalance. This unbalance, in turn, causes unevendistributionofheatinthestatorwindingsleadingtohotspotsandlocaloverheating.Thekeyresultsareillustratedgraphicallybelow.
Power Supply
0 2 4 6 8
0
10
20
30
50
40
60
%
Current unbalance
Voltage unbalance%
Fig. 48 Relationship between voltage and current unbalance
0 2 4 86
Increases in winding temp. in hottest phase
Voltage unbalance
20
40
60
100
80
%
%
120
Fig. 49 Relationship between voltage unbalance and temperature
Current unbalance can be created by the position-ingofthedropcables.Ifjacketedcablesareused,noproblemsshouldbeexpected.Ifsingleleadisuseditisalwaysrecommendtoplacethethreephasecon-
ductorsononesideoftheriserpipeandthenhavetheearthleaddiagonallyopposite.
Voltage transients / lightningPowerlinesaresupposedtodeliversinusoidalshapedwaves on all three phases. The sinusoidal shapedwaves produced at the power station are added tothetransientsinthedistributionsystem.
Sourcesoftransients:1. Frequencyconverterswithoutfilters2. Softstarters3. Contactorsforbigmachines4. Capacitorsforprocessmachines5. Lightning
1. Frequency converters without filters Modernfre-quency converters with an LC or RC filter can beprotected so that they do not produce voltagepeaksabove850Vinconnectionwithcablesofupto100mbetweenfrequencyconverterandmotor.This is fully acceptable and any Grundfos motorwithcorrectratingandcoolingwillhaveanaccept-able life. Frequency converters of the PWM type(PulseWidth Modulation) without LC or RC filteryieldanoutputvoltagewhichdiffersmuchfromtheidealsinusoidalcurvewithtransientsof600Vat400VmainsanddU/dt:2000-2400V/us,meas-ured at a cable length of 1m, depending on themake.Thesetransientswillincreasewithincreas-ingcablelengthbetweenfrequencyconverterandmotor. At 200m, for instance, the transients willbedoubleatthemotorcableplug,i.e.Upeakequals1200VanddU/dt:1200V/us(400Vmains).There-sultwillbereducedlifetimeofthemotor.Becauseofthis,frequencyconvertersmustatleastcontainanRCfiltertoensureoptimummotorlife.
2. Aconnectedsoftstarterwillabsorbanon-sinusoi-dalcurrentandgiverisetoacertaingridnoise.Inconnectionwithveryshortacceleration/decelera-tiontimes,this isofnopractical importanceanddoesnotconflictwithregulationsconcerninggridnoise.Ifthestart-uptimeislongerthanthreesec-onds, the non-sinusoidal transients will overheatthe motor windings and consequently affect thelifttimeofthemotor.
Power Supply
3. Big machines starting DOL or in star-delta con-nectionmaycreatesparksandsendconsiderabletransients back to the grid when the contactorsareopened.Thesesurgescanharmthesubmers-iblemotor.
4. Phase compensation of process plants may con-tain complicated controls with many and big ca-pacitorswhichsendsurgesbacktothegrid.Surgescanbeharmfullforsubmersiblemotors.
5. Aseverestrokeof lightningdirectlyonawell in-stallation, starter or power supply will generallydestroyalllivingorganismsandallelectricalinstal-lations.Thetransientsfromsuchastrokeoflight-ningwillbeatleast20-100kVandthegenerationof heat enough to melt the insulation materials.Lightningstrikingthegridwillgeneratetransientswhichwillpartlybeabsorbedbythelightningar-restersintgridsystem.Thefunctionofalightningarrester is to leak the overvoltage to earth. If alow-voltage grid is hit directly by lightning thereis a risk of transients of more than 10-20 kV atthepumpmotorstarter. Ifstarterandmotorarenotcorrectlyprotectedbylightningarrestersandearthing,theinstallationmaybedamaged,asitisinstalled in electrically conducting groundwater,whichisthebestkindofearthingthereis.
Damage to submersible motors from lightning mayariseboth inconnectionwithpowersupplythroughoverheadcablesandundergroundcables.Inareaswithfrequentlightning,thebestprotectionofbothstarterandsubmersiblemotoristoinstalllightningarrestersonthedischargesideofthestartermainswitchandconnectthemtogroundingrodsorifpossibletotherisermainofthewellifthisismadeofsteel.
Attheborehole,lightningarrestersshouldbefittedonthedischargesideoftheisolationswitchground-edtotherisermainandthewellcasing ifmadeofsteel. For deep installations, lightning arresters canbefitted inthemotorcable,too,astransientsdou-blethevoltageina200mdropcable.Butingeneral,lightningarrestersshouldbepositionedsothattheirfunctioncanbecheckedbyperiodicmeggingastheywear out when exposed to much heavy lightning.
If the power supply suffers from heavy lightningtransients,callthepowercompanytohavethemtesttheirlightningarrestersatthetransformerstation.
Ifasystemhasbeenexposedtolightning,allcom-ponents in the starter box should be thoroughlytested.Thecontactormaybeburnedononephasewhich may give rise to voltage and current unbal-ance in the motor. The contactor or the thermalrelay can be burned on several phases which maycausebothundervoltageandunbalance.Thether-malrelaymaybeburnedwhichmeansthatitcan-nottripandconsequentlycannotprotectthemotorwindings.Onlysomeofthemotorswhicharedam-agedbylightningaredestroyedbythestrokeitself;the rest are damaged by consequential effects.Grundfos submersible motors type MS 402 haveaninsulationlevelofupto15kV.This isthemaxi-mumvoltagepeaks,whichthemotorisexposedtoin practice, e.g. in connection with lightning closeto the installation. Lightning directly on the pumpinstallation is excluded here. Additional lightningprotectionisthereforenotnecessary.
Power Supply
7.Installation & operation
Installation & operation
7.1 Wells and well conditionsA well is a hole, stretching from the surface of theearthtotheundergroundaquifer,wheretheground-waterisfound.Thedepthofthewellmayvaryfromafewmeterstoseveralhundredmeters.
Wellsaretypicallydrilledwithspecialdrillingequip-ment,whichisabletopentratethevariouslayersoftheground,suchassand,clay,bedrock,etc.Insidethedrilledholeacasing(pipe)istypicallyinstalled,whichpreventsthewellfromcollapsingaroundthepump.
Belowthecasing,andinlinewiththeaquifer,isan-other‘casing’withfineslots.Thisisthewellscreen,wheretheslotsallowsthewatertoenterthewell.Itholdsbacksandand largerparticles tryingtoenterthewell.Seefig.50.
Toimprovethefilteringfunction,theboreholetypi-callyfeaturesadiameterthatis2-3”largerthanthecasing. A fine sand gravel pack filter is placed be-tweenthecasingandtheaquifer,asshownfig.45.Some casings come with a pre-made gravel packfilter.Madecorrectly, thisfilteringmethodpreventssandandsiltfromenteringthewell.
Fig. 50 Typical groundwater well components
Recommendations on sand content varies from onecountrytoanother.The National Ground Water Association (NGWA) inUSA recommends the following sand limits in wellwater:• 1.10 mg/l in water used for food and beverage
processing.• 2.50mg/l inwaterforprivatehomes, institutions
andindustries.• 3.10mg/linwaterforsprinklerirrigation,industrial
evaporativecoolingandotherapplicationswherea moderate content of solids is not particularlyharmful.
• 4.15mg/linwaterforfloodirrigation.
6 7
Installation & operation
Iftheconcentrationofsandexceeds15mg/l,somuchmaterialwillberemovedfromthewellthattheaq-uiferandthestrataabove itmaycollapseandthusshortenthelifeofthewell.
Grundfospermitsasandcontentofnomorethan50ppminthewellwater.Withasandcontentof50mg/l,thepumpefficiencyandthelifttimewillremainac-ceptableforupto25,000-35,000dutyhours,equaltoapprox.fouryearsofoperationforeighthoursaday.
If the well water has a sand content higher than50mg/l,aspecialpumpandmotorisavailableonrequest.
Beforethewellcanbeputintooperation,itmustbede-veloped.Anewwellwillalwaysproducesomesandandsiltinthebeginning,andwelldevelopmentistheproc-essofpumpinganewwellfreefromsandandsilt.Itisdonebypumpingwithaveryhighflow,whichdrawsthe fine particles in the aquifer into the filter of thewell.Thisslowlymakesthefiltermoreeffective.Afterapproximatelyonedayofpumping,thewellisnormallypumpedclean,andisreadyfornormaloperation.
Thepumpusedforwelldevelopmentwearsoutrela-tivelyquicklybecauseofthehighsandcontent,andit should therefore always be replaced with a newpumpassoonasthewelldoesnotproduceanymoresand.
Thepumpmustalwaysbeinstalledabovethescreenarea of the casing. In this way, you ensure that thewater is forced past the motor, providing adequatemotorcooling.Ifthepumpcannotbeinstalledabovethe screen filter, a cooling sleeve is always recom-mendedtocreatethenecessaryflowalongthemo-torforpropercooling.Seechapter10.
7. Pump settingPump setting is the depth at which the pump hasbeeninstalledbeneaththeground.Thepumpmustbeabletoliftthewaterfromtheaquifertothesur-faceanddeliveracertainminimumpressure.
Whenthepumpisinstalled,thedrawdownandthedynamicwaterlevelmustalwaysbeknown.Duringoperation,thewatermustneverfallbelowtheinletofthepump.Theriskofcavitationisnormallyverysmall with submersible pumps. However, NPSH ofthe specific pump in its duty point, should alwaysbechecked.
Minimumpumpinletsubmergenceinmeters:NPSH(m)–10(m).
Fig. 51 Static and dynamic water level
7. Pump and motor selectionPleaseseechapter4forsizingandselectionofsub-mersiblepumps.
7..1 The duty pointThedutypointofthepumpistheflowwherepumpefficiencyisbest.Thepumpmustbeselectedsotherequiredflowisascloseaspossibletothedutypoint,orslightlytotherightofthedutypoint.
Installation & operation
7.. Well diameterIngeneral,thelargerthediameterofthepump,thehighertheefficiency.
However,thepumpmustbeabletofitintothewell,and a certain minimum clearance between motorsurface and internal well diameter is therefore al-waysrequired.
Inacorrectlydesignedwell,withthewellscreenbe-lowthepumpandmotor,thewaterhastopasstheclearance between the casing and the motor. Thiswillcauseafrictionloss.
Ifatthesametimethemotoriseccentricpositionedinthewellwithonesideagainstthecasing,thesin-glesidedinletofwaterintothepumpwillcreatetur-bulencesandaffecttheperformanceofthepump.
Fig.52showsthefrictionlossforclearancefrom4to16mmina6“well,andfig.53isshowingthesamefora8”well.
Boththeturbulenceandthefrictionlosswillresultinpumpunderperformance,which insomesituationscanbeextreme.
In wells with well screen area positioned abovethepump,thewaterhastopasstheclearancebe-tweenthepumpandthecasing,whichwillcauseafrictionloss.
Ifatthesametimethepumpispositionedeccentricagainstthecasing,itwillrestricttheinflowathalfofthesuctioninterconnecter.ThissinglesidedU-turnof inlet water will create inlet turbulence affectingthefunctionofthepump.
Fig.54showstheworstcaseturbulence/frictionlossat6”pumpsin6”wellsofdifferentdiameters.
Fig.55showstheworstcaseturbulence/frictionlossat8”pumpsin8”wellsofdifferentdiameters.
Theturbulenceandfrictionwillbeseenasunderper-formanceofthepump.
7.. Well yieldManypumpsareabletooverpumpthewell,whichmeans itwill rundry inashortperiodof time.Thepumpmustbeselectedwithduerespecttotheca-pacity of the well, so overpumping is avoided. Wethereforerecommendmonitoringthewatertable.
Severalproblemsmayarisefromoverpumping:• Dryrunningandpumpdamage• Infiltrationofnon-potablewater,i.e.seawater• Chemicalreactions inthewellwhenoxygencon-
tactsthedryaquifer.
Excessive drawdown also triggers increased powerconsumption,sinceitmustbecompensatedwithad-ditionalpumplift.
7.. Pump efficiencyAllpumpshavetheirpeakefficiencyoverarelativelynarrow flow range. This range is normally used toselectthepump.AGrundfosSP46has itspeakeffi-ciencyatandaround46m3/hflow,justasSP60liesaround60m3/h,andsoonforallotherSPpumps.
Iftheflowrequirementfallsbetweentwomodels,i.e.66m3/h,bothanSP60andanSP77maybeusedwiththesameefficiency.Someoftheothercriteriacomeintoplayasaresult:• Welldiameter(seechapter7.3.2)• Wellyield(seechapter7.3.3)• Sparecapacity.
8 9
0 10 60 807050403020
20
10
0
30
40
50
60
m³/h
Friction loss m
Friction loss in metres at each metre of motor length, whenwater is passing ∆D mm between motor and 6" casing
Wall side positioning
m
6" casing
∆D
D1D2
D3
D4D5
∆D = 1 m of motor length
Flow
Capacity
(delta) D1 = 4 mm(delta) D2 = 7 mm(delta) D3 = 10 mm(delta) D4 = 13 mm(delta) D5 = 16 mm
40 60 160 20018014012010080
20
10
0
30
40
50
60
m³/h
Friction loss m
Capacity
Friction loss in m at each m. of motor length, whenwater is passing ∆D mm between motor and 8" casing
Wall side positioning
m
8" casing
∆D
D1
D2
D3
D4
D5D6
∆D = 1 m of motor length
Flow
(delta) D1 = 7 mm(delta) D2 = 10 mm(delta) D3 = 13 mm(delta) D4 = 16 mm(delta) D5 = 22 mm(delta) D6 = 64 mm
Fig. 52 Friction loss, 6”
Fig. 53 Friction loss, 8”
Installation & operation
0 10 60 807050403020
10
5
0
15
20
25
30
m³/h
Turbulence loss/Friction loss m
U-turn inlet turbulence and friction loss in metres at each metre ofpump length for 6" SP-pumps in 6" wells, wall-side positioning
Wall side positioning
Filter of well
P
6" casing
C1 C2 C3
C4
Friction loss for each m of pump length
Flow
Flow
Cable guardC1 PVC 160 casing Internal diameter: 145 mmC2 PVC 160 casing Internal diameter: 148 mmC3 PVC 160 casing Internal diameter: 151 mmC4 Steel casing Internal diameter: 153 mm
40 60 160 20018014012010080
10
5
0
15
20
25
30
m³/h
Turbulence loss/Friction loss m
U-turn inlet turbulence and friction loss in metres at each metre ofpump length for 8" SE-pumps in 8" wells, wall-side positioning
Wall side positioning
Well screen
P
8" casing
C1 C2 C3
Friction loss for each m of pump length
Flow
Flow
Cable guardC1 PVC casing Internal diameter: 185 mmC2 PVC casing Internal diameter: 188 mmC3 Steel casing Internal diameter: 203 mm
Fig. 54 U-turn, 6”
Fig. 55 U-turn, 8”
Installation & operation
60 61
Installation & operation
7.. Water temperatureThe limiting factor is the submersible motor andcoolingofthemotor.Coolingisthekeytoalonglife-timeofthemotor.
Submersiblemotorsinstalledatmaximumacceptablewatertemperaturemustbecooledataflowrateofatleast0.15m/s,whichensuresturbularflow.Thisveloc-ityisensuredbynotlettingthepumpflowdropbelowacertainminimumvalue.Seefig.56.
Inlargediameterwellsortanksitmaybeneccessaryto use a flow sleeve to increase the flow along themotortominimun0.15m/s.Seechapter10aswell.
Inthediagrambelow,themotorisassumedtobepo-sitionedabovethescreensetting.
Maximum water temperature:Themaximumtemperaturesshownbelowarebasedonflowalongthemotorof0.15m/sMS402 30°CMS4000 40°CMS4000I 60°CMS6000 40°CMS6000I 60°CMS6T30 30°CMS6T60 60°CMMSwithPVCwire: 25°CMMSwithPE2/PAwire: 40°C
Water temperatures above the temperature limitGrundfosMS402motorsmustnotbeusedatliquidtemperaturesabove30°C.OperationwithMS4000and MS6 is possible at a liquid temperature abovethegiventemperaturelimit, ifthemotorisderated(Seefig.57inchapter7.3.6).
Ingeneral,however,thiswillshortenthe lifeofthemotor. It is impossible to say by how much, as thisdependsonanumberofotherparameters,e.g. thevoltagesupply,motorload,motorcoolingconditions,etc.Followingtherecommendationsinthismanualhowever,shouldprovideanacceptablelifetime.Inthesecases,werecommendthatthepumpisserv-icedandall rubberpartsreplacedeverythreeyearsinordertokeepconstantefficiencyandensureanor-mallifetime.
Atoperationabovethetemperature limit,warrantyissuesmustalwaysbeagreedupon.NowarrantycanbegivenwithoutderatingandMP204protection.
7..6 Derating of submersible motorsMultiplythemotorsize(P2)withthederatingfactor.ThisgivesthederatedmotoroutputP2.That is themaximum load that may be applied on the motor.Inmanycasesthisresultsinamotorthatisonesizebiggerthanoriginallycalculated.
Fig. 26 rettet.
Fig. 28 godkendt.
Fig. 29 godkendt.
Fig. 30a godkendt.
Fig. 30b godkendt.Fig. 31 godkendt.
Fig. 56 Maximum full-load cooling water temperature
Installation & operationFig. 24b rettet.
Fig. 24a rettet.
Fig. 25 rettet. Fig. 27 rettet.
Fig. 23 godkendt.
Fig. 20 godkendt.
Fig. 57 Derating of submersible motors
Example: AMS6T30withstandardrating,P2=30kW,isabletoproduce30x0.9=27kWin40°Cwateratacoolingflowrateof0.15m/s.Thesubmersiblemotorshouldbeinstalledattherecommendeddepth.
PleasenotethatderatingofMS4000IandMS6T60isnotrecommended.
7..7 Protection against boilingInordertoprotectthemotoragainstboilingatpumpstopandconsequentlyacoolingwaterstop,itshouldbeinstalled5mbelowthedynamicwaterlevel.Thiswillraisetheboilingpoint.
Fig. 58 Required water temperature/installation depth of MS 4000 and MS 6000
ForMS4000andMS6,thebestandsimplestprotec-tion against overload and excessive temperaturesis to measure the motor temperature by means ofanMP204.Forothersubmersiblemotors,aPt100/Pt1000maybeusedtomonitorthetemperature.
7..8 Sleeve coolingFlowpastthemotormustbeaminimumof0.15m/sinordertosecurepropercoolingofthemotor.
If theminimumflowpastthemotorcannotbeob-tained the natural way, Grundfos offers a range ofcoolingsleevesthatensurecorrectflowandcooling,andareeasytoworkwith.Flowsleevesaretypicallyusedwhenthepumpisinstalledinareservoirortank,orinawell,wherethewaterflowstothepumpfromabove,andthereforedoesnotcoolthemotor.Theremustbereasonablespacingbetweenthecasingandtheouterdiametertolimitthepressuredrop.
6 6
Installation & operation
Therecommendedmin.spacingbetweencasingandflowsleevemaybecalculatedfromtheformulabe-low:
v = Q x (D – d)
v=m/s.Mustbemax.3m/stolimitheadlossQ=m3/hD=Casinginnerdiameterinmmd=Flowsleeveouterdiameterinmm.
1. If the well water contains large amounts of iron(and iron bacteria), manganese and lime, thesesubstances will be oxidised and deposited onthemotorsurface.This isapprox.5-15°Cwarmerthan the influx water. In case of slow flow pastthe motor, this build-up of a heat insulating lay-er of oxidized minerals and metals may resultin hot spots in the motor winding insulation.Thistemperatureincreasemayreachvalueswhichwillreducetheinsulatingabilityandconsequentlythemotorlife.Acoolingsleevealwaysgivesatur-bular flow past the motor. Turbulent flow givesoptimum cooling irrespective of the character ofthedeposits.
2. Ifthegroundwaterisaggressiveorcontainschlo-ride,thecorrosionratewilldoubleforevery15°Cincrease in water temperature. A cooling sleevewillthereforereducetheriskofmotorcorrosion.
3. Atthetopofthewell,oxidisedrawwaterisfound.Eachtimethepumpstarts,thewaterlevelinthewell is lowered.This draws new oxygen into thewell.Thisoxidationofthetopfewmetersisharm-less unless the oxygen reaches the screen. If theinfluxofrawwaterthroughthescreenwithalowcontentofoxygenismixedwithwatercontainingfreshoxygen, iron,manganeseand limewilloxi-dizeandbedepositedinthescreenslots.Thiswillreducetheefficiencyandconsequentlythecapac-ityofthewell.Awarmsubmersiblemotorwithoutcoolingsleevewillheatupthesurroundingwaterwhenswitchedoff.
The thermal effect will make the heated watermovetowardsthetopofthewell.Atthesametime,
oxidizedwaterwillmovetowardsthescreensetting.When using a cooling sleeve, the motor will run atalowertemperatureandwhenthemotorstops,thecoolingsleevewillabsorbtheresidualheatfromthemotorandconsequentlypreventwaterfrommovingupwardbecauseofthethermaleffectandoxidatedwater from moving downward.This will contributetolongerperiodsbetweenwellscalings.
For these applications, the risk of local heatingshouldbeconsidered,particularlyinconnectionwithhorizontalinstallationsandwhereseveralpumpsareinstalled next to each other. In such cases, coolingsleevesshouldalwaysbeused.
7. Riser pipe selectionThechoiceofrisermaindependsonseveraldifferentfactors:• Dischargepressureandinstallationdepth• Theaggressivityofthegroundwater• Frictionloss/operatingcost• Accessibilityandcostofalternative• Priorityofinitialcostsinrelationtoserviceandre-
paircostsatalaterstage.
0 50 100 150 200 250 300
0
5
10
15
20
25
30
35
Installationdepth [m]
Pressure at ground level [bar]
PN 6PN 10
PN 16
PN 24
PN 36
Fig. 59 Required pipe pressure class at different instal-lation depths and actual pressure at ground level
The aggressivity of most groundwater is so moder-atethatcoatedorgalvanizedsteelpipeswillbefullyacceptable.
Installation & operation
PELorPEMrisermainsareprimarilyusedfordomes-ticapplications.Incaseofwaterwhichissoaggres-sive that itwillattackeventhebeststainlesssteel,replaceablezincanodesshouldbefittedinordertoprotectmotorandpump.Insuchinstallations,itwillbetooexpensivetoprotectstainlesssteelrisermainsagainstcorrosion.
InsuchcasestheWellmasterisrecommended.Seechapter10.
Friction loss in riser mainsFrictionlossinpipesorhosescontributessignificant-lytothepowerconsumptionofasubmersiblepump.A small diameter steel pipe is cost-wise attractive,butitcreatesalotofinternalfriction,andovertimethis isgoingto increase.Theresult ishigherpowerconsumptionandcosts.
A larger diameter stainless steel pipe represents alargerinvestment,butthelowerfrictionlossrequiresless energy for pumping. The smooth internal sur-faceisretainedeasier,requiringlessmaintenanceforcleaning.
Example:Flowis54m3/h,or15l/s.
Friction loss in100mof3”pipeand 100mof4”pipeiscalculatedfromafrictionlosstable.
3”pipe:14m4”pipe:3.8m
Choosinga4”pipeinsteadofa3”pipesavesmorethan10mheadper100mofpipe.Theenergysavingsarecalculatedasfollows:
kWh = Q x H 67xη = x 10.
67x0.6 = . kWh
Flexiblehosesspeciallydesignedforpressurisedwa-ter, like Wellmaster, are an alternative to stainlesssteel pipes. Some types are even approved for usewithpotablewater.
This solution is generally recommended as a riserpipeforsubmersiblepumps.Becauseofthehosede-sign,thediameterwillswellslightlywhenthehoseispressurised,andthusdecreasefrictionloss.Atthesametime,italsopreventsthebuiltupofscalingonthesurface,wheretheconstantchangeofthediam-eterforcesthescalingtobreakoff.
The hose solution also makes pump pulling fastercompairedwiththetraditionalpipingsolution,andisthereforealsorecommendedwhenfrequentpull-ingforservicehastobedone.
Never use fire hoses, nylon hoses or the like whichage quickly, and do not have the required pressurerating.Thereisariskthatpumpandmotorwillfalldownintothewellwhichmayrequirethedrillingofa new well. Remember to attach a wire to all hoseinstallations to prevent the pump from falling intothewell.
The disadvantage of flexible hose solutions is thatsometimes it is difficult to prevent the hoses fromgettingintocontactwiththeground.Thiscancausecontamination from bacteria and germs, which can-notberemovedunlessyouemployexpensivespecialequipment.Whendimensioningrisermainsandraw-waterpipesbymeansofdiagramsorPCprogrammes,remembertouseapipesurfaceroughnessof1mm.
7. Cable selection and sizingThe drop cable is the cable running from the wellheadtothemotorcablethatisattachedtothesub-mersiblemotor.
Normally,thedropcablehasfourwires,whereoneisaground/PEwire. Insome local areas,aground/PEisnotrequired.Alwayschecklocalregulationaboutgroundingbeforecabletypeisselected.
Othercriteriafordropcableselectionare:1. Currentcarryingcapacity2. Voltagedrop3. Waterqualityandtemperature4. Drinkingwaterapprovalrequirements5. Regulations
6 6
Installation & operation
Current-carrying capacitySubmersiblepumpdropcableisneverdimensionedfor the locked-rotor current, as the motor starts upin less than 1/10 of a second. Always use the fullloadcurrentfromthenameplateasthedimension-ingcurrent.Theentirelengthofthedropcableisnotsubmerged inwater,soadditionalcoolingfromthewatermaybeencountered.
Typicalguidelinesformax.ampsinsubmersibledropcables:
Dimension(mm2) Max.current(A)1.5 18.52.5 254 346 43
10 6016 8025 10135 12650 15370 19695 238
120 276150 319185 364240 430300 497
Pleasealwayscheckthelocalguidelines,whichover-rulethetableabove.
Voltage dropThecablemustbesizedsothevoltagedropdoesnotexceed3%.Undernocircumstancesmustthevoltageatthemotorterminalsbelowerthantheminimumvoltageforthemotor,whichistheratedvoltagemi-nus10%.
Themaximumlengthiscalculatedaccordingtotheformulasshownbelow:
Max. cable length of a single-phase submersiblepump:
L = U x ∆U l x x 100 x (cosφ x + sinφ x Xl) [m]
Max. cable length of a three-phase submersiblepump:
L = U x ∆U l x 1,7 x 100 x (cosφ x + sinφ x Xl) [m]
U = Ratedvoltage[V]U = Voltagedrop[%]I = Ratedcurrentofthemotor[A]ρ = Specificresistance:0.02[mm²/m]q = Cross-sectionofsubmersibledropcable[mm²]XI= Inductiveresistance:0.078x10-3[Ω/m]
Water quality and temperatureThebestcablematerialforcleanwaterisEPR(EPMorEPDM).Thismaterialhasgoodelectricpropertiescombinedwithagoodresistancetowater.Thistypeofcableisalwaysrecommendedwhenthepumpedwater isnotcontaminatedwithhydrocarbons.EPRoffersonlylimitedresistancetohydrocarbons,how-ever.
Inlighterhydrocarbonsolutions,aChloroprenecablemaybeused.
Inheavierconcentrationsofhydrocarbonsitmaybenecessary to use PTFE (Teflon) jacketed cable. TheSPEversionof theSPpumpscomesstandardwithPTFEmotorcable,andmakesitsuitableforpump-ingwaterwithahighcontentofhydrocarbons.
A lower cost solution is a standard Chloroprenetypeofcable.SpecificationsmaybeobtainedfromGrundfos.
When the water temperature increases, the cablemustbederated.Thecurrentcarryingcapacityofthedrop cables is usually valid at 30°C. At higher tem-peratures, this must always be compensated in ac-cordancewiththetablebelow.
Installation & operation
Cabletype TML-A-B H07RN
Insulationmaterial
EPR NR/SR
Ambienttemp.°C Correctionfactor Correctionfactor
10 1.18 1.29
15 1.14 1.22
20 1.10 1.15
25 1.05 1.05
30 1.00 1.00
35 0.95 0.91
40 0.89 0.82
45 0.84 0.71
50 0.77 0.58
55 0.71 0.41
60 0.63 -
65 0.55 -
70 0.45 -
Drinking water approvalAllGrundfosmotorsoutsideNorthAmericaandJa-panaredeliveredfromfactorywithdrinkingwater-approvedmotorcables.Ifthepumpisusedforpump-ing potable water, Grundfos always recommendsalsousingadropcablethathasadrinkingwaterap-proval.
RegulationsLocal regulations must always be checked and fol-lowed.
7.6 Handling
7.6.1 Pump / motor assemblyGrundfos submersible pumps and motors are allmadeinaccordancewithNEMAstandards.Theyarefully compatible with pumps and motors that con-form to these standards as well. Grundfos recom-mendsalwaysusingonlyaGrundfospumptogetherwithaGrundfosmotorandviceversa.
Fordetailedassemblyinstructionspleaseseethein-dividual installation and operating instructions forSPpumps.
7.6. Cable splice/connection of motor cable and drop cableFaultyorunapprovedcablejointsarefrequentcausesofburned-outmotors.Grundfos-recommendedprod-ucts or products of similar quality should be chosenandthemanufacturer’sguidelinesfollowed.Anycablejointmustbewatertightandhaveaninsulationresist-anceofminimum10megaohms,measuredinasub-mergedstateafter24hoursinwater.Inordertoobtainthis,allcablepartsmustbe100%cleanandallotherrequirements indicatedintheservicemanualandinservice video programmes observed. There are fourwaysofmakingacablejoint.
1. Heat shrinkHeatshrinkisaplastictubewiththeinsidecoveredwithglue.Whenexposedtoheat,itwillshrink,andthegluemelts,andmakesawatertightcablesplice.Ittakesalotofpracticetoperformthiskindofjoint.Furthermore,hightemeraturearerequiredforlargecabletypes.Lightersandhobbyheatersarenotsuffi-cient.Theadvantageofthisprincipleisthatthecon-nectiondoesnotrequiretimefordryingbutisreadyimmediatelyafterfitting.
. ResinSealingwithresinistheoldestandbestknowntypeofjoint.Itisalsothejointwhichissimplesttocarryoutcorrectly.Itcanbeperformedinthefieldwithoutspecialtools.Thedisadvantageisthatitmusthardenforatleast24hours.Asfarasthepriceisconcerned,thereisnodifferencebetweenthisandshrinkflex.
. TapeIt is important to use special tape for connectingsubmersiblecables.Tapejointsshouldonlybeusedatwaterpressuresbelow5m.
. Plug connectionItisimportantnottousecablejointkitsortapewhicharemorethanthreeyearsold.Thisagelimitshouldbereducedtooneyearifstoredabove15°C.Alwaystestthecablejointduringmaintenance.
Motor cable plugThe motor cable plug must always be fitted at thetorque stated in the documentation. In case of lu-
66 67
Installation & operation
bricationofthecableplug,anon-conductivemate-rialshouldbeused(e.g.siliconepaste).Motorcableplugsthataremorethanthreeyearsoldshouldnotbereused,astheymayhavelosttheabilitytomakeasafe,watertightconnection.
7.6. Riser pipe connections Submersible pumps are available both with RP andNPTthreads,aswellasflangesinvariousstandards.In general, however, Grundfos recommends fittinga50cmlengthofpipefirsttothepump.Thisgivesgoodhandlingof the pump duringthe installation,asthepumpdoesnotbecometoolong.Italsoleavesroomfortheclampwhichholdsthepumpuntilthenextpipehasbeenfitted.
As an alternative to a threaded connection, variousflange types can be offered: Grundfos flanges, JISflangesandDINflanges.
Pipe connections and installationGrundfosstandardflangesaremadeparticularlyforfittingintoawell.Thismeansthattheydonotcom-ply with any national nor international standards;theyhavebeendimensionedtowithstandGrundfospumppressures.
There are several advantages in using Grundfosstandard flanges instead of other flanges.They arenot only cheaper, and because of their dimensiontheyareeasiertofitintothewell.Grundfos can supply counter flanges for Grundfosflanges,whichcanbeweldedontothefirstpipe.
7.7 Pumps in parallel operationParallelpumpingoperationisoftenusedwithavari-ableconsumptionpattern.Asinglepumpoperationwouldrequireahighcapacitypump,wherethesparecapacity is only used in a very short period.The in-vestment would be very high, and the operationalefficiency too low.The peaks may also result in ad-ditionaldrawdownofthedynamicwaterlevelwithanumberofwater-andwellqualityissuesasaresult.
Theseproblemsaretypicallyavoidedbyusingoneofthefollowing:1. Severalsmallercascadeoperatedpumps(addition-
alpumpsstartsandstopsasdemandchanges)2. Frequency control of the pump via a pressure
transducer3. Acombinationof1and2.
Forcorrectpumpselection,thewell’scharacteristicsmust be known, either from the well log or a testpumping.
7.8 Pumps in series operationWith pump setting deeper than the max. head ca-pacityofastandardSPpump, itmaybecoupled inserieswithaBMpump(SPinsleeve).Seefig.60.
Installation & operation
Fig. 60 Series coupled submersible pump
7.9 Number of start/stopsInordertogetamaximumlifeoutofthesubmersi-blepumps,thenumberofstartsmustbelimited.Itisusuallythemotorthatisthelimitingfactor.Itisalsonecessarytostartthemotoratleastonceperyeartoavoiditfromseizingup.
The table below shows the recommended max.numberofstartsfordifferentmotortypes:
Incl.N,RandREversions
Min.startsperyear
Max.startsperhour
Max.startsperday
MS402 1 100 300MS4000 1 100 300MS6/MS6000 1 30 300MMS6000 1 15 360MMS8000 1 10 240MMS10000 1 8 190MMS12000 1 5 120
7.10 Pump start-up Detailed information about methods for reducinglocked-rotorcurrent,seechapter5.
You should always follow the instructions found inthe installation and operating instructions for eachpumpregardingstartup.Forpumpsinseriesconnections,remembertostartthem in the correct sequence: the pump with thelowestambientpressuremustbestartedfirst.
For pumps in parallel operation, remember that airventingpossibilitiesarealreadybuiltintothesystem.Thiswillpreventairlocking.
7.11 VFD operationSeechapter5.
7.1 Generator operationEnginedrivengeneratorsforsubmersiblemotorsareoftenofferedaccordingtostandardconditions,e.g.• Max.altitudeabovesealevel:150m• Max.airinlettemperature:30°C• Max.humidity:60%.
68 69
Installation & operation
Iftheselimitsareexceeded,thestandarddieselen-gineandpossiblythegeneratorhavetobederatedinordertogivethemotorsufficientpowersupply.
When ordering a generator set, altitude, air inlettemperatureandmaximumhumidityshouldbegiv-entothemanufacturertohavethegeneratorfactoryderated.Generatorsetsforthree-phasesubmersiblemotorsmustbeabletowithstand35%voltagereduc-tionduringstart-up.
For the selection of internally regulated generatorsavailable, stick to the tables below for continuousbreak kW for single-phase and three-phase motorswithDOLstart.
Examplesofderatingfactorsforstandarddieselengines
Examplesofderatingfactorsforstandardgenerators
Altitude:3.5%forevery300mabove150mabovesealevel(2.5%forturbo-chargedengines).
Altitude:2.5%forevery300mabove1000mabovesealevel.
Air inlet temperature:2%forevery5.5°Cabove30°C(3%forturbo-chargedengines).
Air inlet temperature:5%forevery5°Cabove40°C.
Humidity:6%at100%humidity.
Submersiblemotorratingforsingle-phaseandthree-phaseversions[kW]
Generatorrating
Elevationofmax.150mandahumi-dityof100%
Elevationofmax.750mandahumi-dityof100%
Dieselengineratingatanambienttemperatureof
[kW][kW] 30°C40°C[kW][kW]
30°C40°C[kW][kW]
0.250.370.550.751.11.52.23.75.57.5
11.015.018.522.030.037.045.055.075.0
90.0110.0132.0150.0185.0
1.5 1.0 2.0 1.5 2.5 2.0 3.0 2.5 4.0 3.0 5.0 4.0 7.0 6.0 11.0 9.0 16.0 12.5 19.0 15.0 28.0 22.0 38.0 30.0 50.0 40.0 55.0 45.0 75.0 60.0 95.0 75.0 110.0 90.0 135.0 110.0 185.0 150.0 220.0 175.0 250.0 200.0 313.0 250.0 344.0 275.0 396.0 330.0
1.25 1.3 2.0 2.1 2.5 3.1 3.0 3.1 4.0 4.2 5.0 5.2 7.0 7.3 10.0 10.4 14.0 14.6 17.0 17.7 25.0 26.0 35.0 36.0 45.0 47.0 50.0 52.0 65.0 68.0 83.0 86.0 100.0 104.0 120.0 125.0 165.0 172.0 192.5 200.0 220.0 230.0 275.0 290.0 305.0 315.0 365.0 405.0
1.4 1.43 2.3 2.3 2.8 2.86 3.4 3.44 4.5 4.58 5.6 5.73 7.8 8.0 11.1 11.5 15.6 16.0 19.0 20.0 28.0 29.0 39.0 40.0 50.0 52.0 56.0 57.0 72.0 75.0 92.0 95.0 111.0 115.0 133.0 137.0183.0 189.0 215.0 220.0244.0 250.0305.0 315.0 335.0 345.0405.0 415.0
Ifthegeneratoranddieselenginearederatedaccord-ingtothetable,thefollowingcriteriaapply:
1. Thevoltagedropatthegeneratorwillnotexceed10%duringstart-up.Thismeansthatitispossi-bletouseeventhefastestundervoltageprotec-tiononthemarketinthestarterboxofthepumpmotor.
2. Generator and diesel engine will have a normallifeasthenewfullyrun-inengineisonlyloadedapprox.70% withcontinuous pump motor ratedcurrent.Adieselenginewill typicallyhavemaxi-mumefficiency(lowestfuelconsumptionperkWoutput)at70-80%ofmaximumload.
Installation & operation
3. By autotransformer start or installation of aGrundfosMP204forundervoltageprotection, itispossibletochoosebothageneratoranddieselenginethanare20%smallerthanstatedintheta-ble.This,however,meansfrequentmaintenanceofairfilterandinjectionnozzles,cleaningofthecooler and change of oil. Furthermore, it will re-sultinavoltagedropduringstart-upofupto20%.If the loss in the drop cable and motor cable ofupto15%isadded,thetotalvoltagelosswillbemore than 35% at the motor.This is no problemforthree-phasemotors,butsometimesforsingle-phasemotors,whichwilloftenrequireanoversizestartingcapacitorforlowstart-upvoltages.
Therearetwotypesofgenerators:internallyandex-ternally-regulated.
Internally-regulated generators have an additionalwinding in the generator stator and are also calledself-excited. The extra winding senses the outputcurrentand increasestheoutputvoltageautomati-cally.
Internally-regulated generators normally show thebestrunningefficiency.
Externally-regulated generators use an externallymounted voltage regulator that senses the outputvoltage.Asthevoltagedipsatmotorstart-up,thereg-ulatorincreasestheoutputvoltageofthegenerator.
An externally-regulated generator is to be dimen-sioned approximately 50% higher in kW/kVA ratingtodeliver thesamestartingtorqueasan internallyregulatedgenerator.
Generator frequency is all important as the motorspeedvarieswiththefrequency [Hz].Duetopumpaffinitylaws,apumprunningat1to2Hzbelowmo-tornameplatefrequencywillnotmeet itsperform-ance curve. Conversely, a pump running 1 or 2 Hzhighermaytriptheoverloadrelay.
Generator operation Alwaysstartthegeneratorbeforethemotorisstart-edandalwaysstopthemotorbeforethegeneratorisstopped.Themotorthrustbearingmaybedamagedifgeneratorsareallowedtocoastdownwiththemo-torconnected.Thesameconditionoccurswhengen-eratorsareallowedtorunoutoffuel.
70 71
8.Communication
Communication
8.1 Purpose of communication and networking Therearetwomainpurposesofusingdatacommu-nicationandnetworkinginrelationtoequipmentandmachineryinallindustrialinstallationsorinprocessinginstallationslikewatersupplyplants:
To centralise supervision and controlItiswelldocumentedthatmostautomationsystemscanbenefitsubstantiallyfromcentralisationofcon-trolandsupervision.Theissuesthataremostoftenmentionedare:• Optimise performance (e.g. energy and material
savings)• Optimiseprocessquality(correctiveactions)• Bettermaintenance(serviceondemand)• Reductionofrunningcosts(e.g.staffcutting)• Organised/quick reaction to faults (minimise
downtime)• Easyaccesstocurrentdataandthepossibilityto
storedataindatabases(reportgeneration)
Systems for this kind of central management arecalledSCADA systems(SupervisoryControlandDataAcquisition)
To realise distributed systems Manyoftoday’sautomationsystemswouldneverberealisablewithoutdatacommunication.Inanauto-mationsystem,discreetdevices,whicharephysicallyseparated,havetoexchangedata.Thesearetypicallyintheformofmeasuredphysicalvalues,commandsandsetpoints.Thediscreetdevicesworktogethertofulfilasuperiorpurpose(e.g.supplyingwater)andbydoingsotheyconstitute what is called a distributed system. Eachdeviceislikeacomponentinalargerentity,contrib-utingtotheoverallperformance,efficiencyandreli-abilityofthesystem.The number of discreet devices can often be veryhugeandsocanthedistancebetweenthem.Inthesecases the communication and networking in itselfbecomesthemostimportantandvulnerablepartofthesystemanditsabilitytofulfilitspurpose.
It is important that the selection of network andcommunicationsprotocolisnotalimitingfactorfor
thesystemperformanceandespeciallythatitisnotalimitingfactorforthefuturegrowthandflexibility.
8. Communications and networking technologyTheuseofcommunicationandnetworkingisinevitableinmodernautomationsystems,butthekindofsystemandtheusedtechnologyisverydiversified.Systemsmadebefore1995wherealmostalwaysbasedonelectricalcables,whereasthetech-nologytodayofferfiberopticsorradiocommunica-tionasanalternative(orcombined)solution.
Opticalfibersareflexibleandcanbebundledasca-bles.Itisespeciallyadvantageousforlong-distancecommunications,becauselightpropagatesthroughthefiberwithlittleattenuationcomparedtoelectri-cal cables. Additionally, the light signals propagat-inginthefibercanbemodulatedatratesashighas40Gb/s,andeachfibercancarrymanyindependentchannels, each by a different wavelength of light.Fiberisalsoimmunetoelectricalinterference,whichalso means immunity to damaging voltage surgesinducedbylightning–abigadvantagewhenusinglong-distancecablinginoutdoorinstallations.
Communication using radio signals falls in twocategories:Shortdistanceandlongdistanceradiocommunication.WeknowthetechnologyofshortdistanceradiocommunicationfromwirelessLANs.Mostfieldbussesofferwirelessrepeaterstoextendthe fieldbus communication distance over rela-tivelyshortrangesortoavoidusingcableswherecablingwouldbecostlyorimpractical(e.g.movingdevices).
Long distance radio communication can be basedon private radio telemetry.The UHF band between400MHz to 500MHz has become internationallyadopted for low power license-free use for digitaldataandtelemetrysystems.Ithastheadvantageofpropagatingindirectlineofsightandwillpenetrateconventionalbuildingmaterials.Fordistancesabove1000m,radioswithhigherpowerrequiringalicensedchannelistypicallyneeded.
7 7
Communication Communication
SCADAsystemsoftwareoftenhasnetworkserverca-pability,meaningthatifthehostPCisconnectedtoaLANortotheinternet,itwillbepossibletologonto the system remotely from another network con-nectedPC.TheSCADAsystemsoftwareisastandardpackage(availablefrommanydifferentsoftwareven-dors),butwithahighdegreeofcustomizedadapta-tion(data,functions,graphics,etc).
1. Establishthehealthofthesystem – IssystemOK(operatingasintendedandfulfill-
ingitspurpose)? – Doesthesystemneedservice(causeandkind)? – Isthesystembrokendown(cause)?2. Displaysystemvariables/conditions – Conditions(likeon/off)illustratedwithgraphics
andcolors – Importantsystemvariablesdisplayedonsystem
drawing(pressure,flow,etc.) – Importantsystemvariablesshowngraphically3. Alarmloggingandalarmrouting – Managingdutyrosters – Routingofmessages(e.g.SMS)4. Datalogging/Retrievalofloggeddata – Interfacetodatabase(e.g.MicrosoftSQL) – Dataprocessing/Datastoring/Graphicalvisu-
alization5. Control – Manuallyoperation – Automaticoperation – Closedloopcontrol(rare)6. Setup – Displaymainsetupparameters – Changingofmainsetupparameters7. Maintenanceinformation – Maintenanceplanandhistory – Sparepartslist – Manuals,photos,instructivevideos8. Expertsystem – Artificialintelligence – Faultdiagnostics – Decisionsupport9. InterfacingtoEnterpriseResourcePlanning(ERP).
8.. Web-hosted SCADA ASCADAsystemsoftwarewhichrunsonawebserverinsteadofonanormalWindowsPCiscalledaweb-
hosted SCADA system. All data is accessible via theinternet by the use of a web-browser (e.g. InternetExplorer).Thesubsystemscanbemonitoredandoperatedfromany PC in any location with internet access all overthe world.There is no need to install an expensivesoftwaresystemononeormorePC.
TheSCADAsystemsoftwareandallthedataresidesonthewebserver,whichcouldbeoperatedbyacon-tractor(systemintegrator)orbythecustomer(e.g.acentralwebserverforacompletemunicipality).
The customer/user doesn’t have to worry about in-formation, communication and software/hardwaretechnologybutcanconcentrateonthepracticaluseofthedataandthepracticalmaintenanceofthesub-system.
Passwordsensurethatonlyauthorisedpersonnelre-cievesaccesstooperatespecificsubsystems.
Server/computer
ClientClient Client
Subsystems
WWW
Fig. 62 Illustration of the princible in web-hosted SCADA
Forradiocommunicationinareasthatarecoveredbyexistingoperator networkslikeGSMtheeasiest(butnotalwaysthecheapest)wayofestablishingremotecommunication is by subscription to this service. Itis up to the customer (or the system integrator heis using) to examine and assess if the demands forcommunicationspeed,responsetimeandreliabilityarefulfilled.
InrecentyearsEthernetnetworkingtechnology,withthecommunicationsprotocolTCP/IP,whichhastra-ditionallybeenusedforLANsandwhichhasbecometotally dominating within that field, has started tomigratetofieldbusapplications.Hereitnowentersinto competition with the traditional fieldbusseslikeDeviceNet,Profibus,Modbus,etc.,butinsteadofrepresentingonecoherentprotocol,EthernetTCP/IPshowsup inmany incompatiblestandards likeEth-ernet IP (a DeviceNet variant), Profinet (a Profibusvariant),ModbusTCP(aModbusvariant)andsimilarstandards that are based on (and compatible with)corresponding old fieldbusses. The fact that somenew Ethernet standards like EtherCat that are spe-ciallydesignedtoutilizethehighspeedadvantagesof Ethernet have also emerged has not made thechoice and compatibility situation within network-ingofautomationsystemseasier.
8. SCADA systems
8..1 SCADA main partsThethreemainpartsofatypicalSCADAsystemare:
1. A master computerThe computer (e.g. a PC runningWindows or Unix)has HMI (Human Machine Interface) software anda database. Numerous specialized third party HMI/SCADAsoftwarepackagesareavailable.Someexam-plesareiFixfromGEFanuc,CitectSCADAfromCitect,SIMATICfromSiemensandWonderwarefromInven-sys.
. A number of outstationsAnoutstationoftenrepresentsanautonomoussub-system.Autonomousmeansthatiftheconnectionto
theSCADAsystemisbroken,thesubsystemisabletokeeponoperatingaloneandstillfulfillingitspurpose(e.g. supplying water to a tank).The overall systemdesign(choiceoftechnologyandequipment)shouldaimatsubsystemautonomywheneverpossibleandalways without exception ensure that subsystemsarefailsafeandwillreturntoapredictablewell-de-finedandsecurestateifcommunicationwithSCADAisbroken.Theoutstationwilltypicallybe:• APLC(ProgrammableLogicController)• ADDC(DedicatedDigitalController)• Agatewaytoanother(underlying)network
. A communications infrastructureThisiswhattiesitalltogether.Amixoftechnologieswilloftenbeusedasnosingletechnology(networkorprotocol)spansalldemandsinmorecomplexap-plications.
Media Converter
Link PWR Link
RXTX
LAN/WAN
Computer(SCADA software)
HMIHuman Machine Interface
Storage(database)
Communicationinfrastructure
Outstation (DDC)
MPC
Subsystem
Outstation (PLC)
Subsystem
Fig. 61 Illustration of the main parts of a SCADA system
8.. SCADA functionsBelowisalistofthefunctionsthatistypicallyfoundinSCADAsystemsoftwarepackages.Thelistispriori-tizedwiththemostimportantfunctionsatthetop.
7 7
Communication Communication
8. Networking basics
8..1 Network topology
Referstothewayinwhichthenetworkofcommuni-catingdevices isconnected.Eachtopology issuitedtospecifictasksandhasitsownadvantagesanddis-advantages.
In a star network, all wiring is done from a centralpoint (e.g. a hub or a central controller). It has thegreatestcablelengthsofanytopologyandthususesthe most amount of cable. Ethernet networks areusuallybasedonthestartopology.
Fig. 63 Star topology
Advantages Disadvantages
•Easytoaddnewdevices
•Centralizedcontrol,net-work/hubmonitoring
•Hubfailurecripplesallde-vicesconnectedtothathub
Aring network,isanetworktopologyinwhicheachnetworkdeviceconnectstoexactlytwootherdevic-es,formingacircularpathwayforsignals.Datatrav-elsfromdevicetodevice,witheachdevicehandlingeverypacket.Theold IBM LAN standardTokenRingand the industrial fieldbus Interbus are both usingtheringtopology.
Fig. 64 Ring topology
Advantages Disadvantages
•Equalaccessforalldevices
•Eachdevicehasfullaccessspeedtothering
•Onlyslightperformancedropwithincreasedno.ofdevices.
•Costlywiring
•Difficultandexpensivecon-nections
Inabus network,alldevicesconnecttothesameca-blesegment.Wiringisnormallydonepointtopointin a chain fashion or via drop cables. The cable isterminated at each end. Messages are transmittedalongthecablearevisibletoalldevicesconnectedtothatcable.Mostfieldbusses(e.g.Profibus,DeviceNet,GENIbus)usethebustopology,butdespitethename,fieldbussescanalsobebasedonothertopologies.
Fig. 65 Bus topology
Advantages Disadvantages
•Easytoimplement
•Lowcost
•Limitsoncablelengthanddevicenumbers
•Difficulttoisolatenetworkfaults
•Acablefaultaffectsalldevices
•Networkslowsdownwithincreasedno.ofdevices
Veryoftenacombinationofthesethreebasictopolo-giesisused–thenwetalkaboutmixed topology.Ifthe networking technology used allows connectioninanytopology–thenwetalkaboutfree topology.
8.. Communications protocolThe communications protocol covers the rules thatspecifyhowafunctionaldeviceconnectedtoanet-work can interchange data with other devices thatare part of the network. It specifies details in thephysicalhardwarelikeimpedanceandelectricalsig-nals.Itspecifiesdetailsinthedatatransferlikebaudrate,timinganddatapacketformatanditspecifieshow addressing of devices, requesting of data andreplyingtorequestsshouldwork.
Thecommunicationsprotocolisthemanagerofthecommunicationline.Theprotocolrulescontrolwhoisallowedtotransmit,howmuchandforhowlong.In master/slave protocols (like GENIbus, Modbus,Profibus)thearbitrationrulesoftheprotocolcontrolwhoismasterandwhoisslave.
Itistheresponsibilityoftheprotocolthateverythingworks reliably and that data gets communicatedwithout errors. But in cases where something goeswrong, inprotocoltermscalledexceptions, it isalsotheresponsibilityoftheprotocoltodetecttheseex-ceptions, to react upon them (e.g. error reporting,retransmission,etc.)andfinallytorecoverfromanyerror condition including from a complete networkbreakdown.
8.. Functional profileThe functional profile of a network device meansthe specification of its functional interface to thenetwork.This isprimarilyadescriptionoftheinputand the output data of the device. These data aremostoftenreferredtoasthedatapointsorthedataitemsofthedevice.Thefunctionalprofiledescribesthedataitems–whatformattheyhave(8bit,16bit,etc.),theirscaling(resolutionandrange),limitationsandmutualrelation.
Apartfromthedataitemdescription,thefunctionalprofilealsodescribeshowtooperatethedevicevia
thenetwork,whenthedeviceisusedinapplications.Itdocumentstherelationbetweenthedevicefunc-tions,thedataitemsandthebehaviouroftheappli-cation/systeminwhichthedeviceisoperating.
Devicesthatusethesamecommunicationsprotocolandexchangedataaccordingtoadefinedandsharedfunctionalprofilearesaidtobeinteroperable.
8.. The fieldbusThekindofnetworksthatareusedinindustrialau-tomationsystemstoconnectsensors,actuatorandcontrollers are called fieldbusses as opposed to net-worksusedforadministrativepurposesinofficeen-vironments,whicharegenerallyreferredtoasLocal Area Networks (LANs).
Fieldbusses are designed to work in harsh environ-ments–outinthefieldsotospeak-anduseindustri-algradeequipmentandcabling.Moreoverafieldbusprotocol generally promotes other characteristicsthanaLANdoes,becausethedemandsarequietdif-ferent.
The fieldbus typically transfers small amounts ofdata, but the data is transferred frequently (highsample rates can often be a requirement). Also thefieldbus must be able to handle time critical datatransfer,meaningithastofulfilhardtimingrequire-ments(lowdelays inbusaccessanddatareplyandfastdataprocessing).
TheLAN,ontheotherhand,transfershugeamountsof data (files, etc.) between computers and servers,butthesedataaretransferredseldom.Alsothereac-tion need not be very fast, because it interacts withhumansandnotwithtime-criticalphysicalprocesses.
Daisy chain fashion
Drop cable fashion
76 77
Communication Communication
8.. GENIbusGENIbus,theGrundfosElectronicsNetworkIntercom-municationsbusisaproprietaryfieldbusdevelopedbyGrundfostomeettheneedfordatatransferandnet-workingintypicalwaterpumpapplicationsinbuild-ings,watersupply,waterpurificationandindustry.
8..1 BackgroundGENIbuswasfirstintroducedtothemarketin1991asafieldbusinterfacefortheGrundfoscirculatorpumptypeUPE.Thispumpbecamethefirstwaterpumpinthe world with integrated frequency converter andalsothefirstwithintegratedfieldbusinterface.
TheoriginalpurposeoftheGENIbusinterfacewastoenable networking of the speed controlled circula-torpumpsintosubsystems,whereacentralmastercouldhandleseveralcontrolloopswithpumpscon-nected hydraulically parallel and at the same timemake important pump data like pressure, flow andalarmsavailableonadisplay.
SincethenGENIbushasdevelopedintoanadvancedand yet cost effective de-facto Grundfos standardandisavailableforalmostallGrundfosproductswithelectronics.Itsmainareaofapplicationis:
• Networking between pumps, auxiliary devicesandcontrollers inGrundfossubsystems(e.g.Hy-droMPC)
• Integration in automation systems (e.g. SCADA)viagateways
• Connection to PC tools via adapter for configu-ration, faultfinding, value monitoring, data log-ging,etc.
8.. Technical descriptionLike most other fieldbusses, GENIbus supports themechanisms for single-casting (single-addressing),multicasting (group addressing) and broadcasting(global addressing). A unique feature of GENIbus istheConnection Request,whichmakesitpossibleforamasterdevicetorecognizeallconnectedunitsonanetworkwithouthavingtopollthroughallpossibleaddresses.
Having been developed and now being maintainedby a single company instead of by an independentuser organization makes GENIbus a so-called pro-prietary fieldbus. However the standard is open foranyonetouse,whichhasresultedintheemergenceofseveralthirdpartygatewaysenablingtheconnec-tion of GENIbus devices (e.g. pumps) to controllersofotherbrandsandofgateways,whichcanconnectGENIbustoafewrecognizedfieldbusstandards.
Below is a GENIbus technical summary. The com-plete GENIbus protocol specification is available onrequest.
Physicallayer(hardware)
Topology Bus
Transmitter EIARS485,halfduplex
Dataformat Startbit(=0),8databitswithleastsignificantbitfirst,stopbit(=1)
Baudrate 9600bits/sSomedevicessupportprogrammablebaudratefrom1200-38400bits/s
Distance Daisychain:1200mMultidrop:500mTwistedpaircablewithshieldisrecom-mended.Notermination.
No.ofbusunits Max.32
Datalinklayer(timing,verification)
InterByteDelay <=1.2ms
InterTelegramDelay >=3ms
ReplyDelay [3ms;50ms]Somedevicessupportprogrammableminimumreplydelay[3ms;2.5s]
Cyclicredundancychecking
16bitCCITT
Mediumaccess Master/Slave
Physicaladdressrange
Masteraddressrange:[0;231]Slaveaddressrange:[32;231]Connectionrequestaddress:254Broadcastaddress:255
max. 1200 mM
S S S
max. 500 mM
S S S
max. 1200 mM
S S S
AYB
AYB
AYB
Bus unit #1 Bus unit #2 Bus unit #3
Daisy chaining, the ideal way of cabling GENIbus
8.. Cabling guidelines
Ingeneral• Usetwistedpaircableswithshield• Connecttheshieldinbothends• Daisy chaining is the preferred way to connect
multipleunits• Avoidlongstubs• Keepwiresasshortaspossible• Separatebuswiresfrompowercablesifpossible.
GENIbus• Donotuseterminatingresistors• Acommunicationdistanceupto1200misnormal-
lynotaproblem• Thedistancecanbeextendedwithrepeaters• Ifyouexperienceproblemswithnoise,trydiscon-
nectingtheshieldthatisfoundatoneendperbusunit.
78 79
Communication Communication
8.6 Grundfos GENIbus products for SP applications
By the usage of the electronic motor protector MP204(describedinchapter10,“Accessories”)itispos-sibletomonitortheSPpumpremotely:• 3-phasecurrentandvoltages• 3-phasevoltageanglesandcos(θ)• Startcurrent• Currentasymmetry• Insulationresistance• Powerandenergyconsumption• Supplyfrequency• Motortemperature• Presentalarmsandwarnings• Loggedalarms• Powerontimeandrunningtimecounter• Startcounter(totalandperhour)• Re-startcounter(totalandperday)• OperatingmodeofMP204motorprotector.
ByoperatingtheelectronicmotorprotectorMP204asanon/offactuator,itispossibletostart/stopcon-troltheSPpumpremotely.Itisalsopossibletoresetalarms,loggedalarmsandvariouscounterslikerun-ninghoursandstartcounters.
Bytheusageofthe input/output IO111device (de-scribedinchapter10,“Accessories”)aloneortogeth-erwithMP204itispossibletomonitorthefollowingvalues:• ValueofPT100temperaturesensor• Valueofpulsecounterinput• Valueofanalogue4-20mAinput• Alarmlimitexceeded(fortheaboveinputs)• Powerontime• Loggedalarms.
MP204andIO112bothhaveGENIbusinterface.MP204 is supported by the Grundfos gateway G100(datasheetavailableviaWEBcaps),whichcanhandlesimultaneousconnectionofupto32MP204devicesandsupportscommunicationviaModbus(RS232,ra-dioorGSM)orviaProfibus.Italsohasabuildindatalogger with a capacity of approximately 300,000timestampedloggings.
3~
Gateway G100
GENIbus
Contactor
Main network connection (to PLC or SCADA)
MP 204 Motor protector
powerpower MNCpower GENIGENI TxDGENI RxDFault
DCDRTSTxD1RxD1TxD2RxD2
G100 Gateway
MP 204 MP 204 MP 204 MP 204
Fig. 66 Illustration of the remote monitoring and control of SP pump installations
80 81
9.Troubleshooting
Troubleshooting
Fault Cause Solution
Loudnoisesinpipeworkinhomeorbuilding.
Pressuregaugesstopworkingaftershorttime.
Blow-outinpipingandfittings
Waterhammeratpumpstartandstop.
Fita50-litrediaphragmtankwheretherisermainandthehorizontaldischargepipemeet.
Waterfromthisdiaphragmtankwillbedischargedwhenthepumpisswitchedoffandthuspreventtheformationofthevacuum.
Airpenetratingsuctionpipingaswellaspressurisedpiping.
Waterhammercreatingvacuum Introducesoft-start/stop,-VFDorpressuretankshockabsorption.
Arapiddeclineinpumpperform-ance.
Wearandtearduetosand/siltpenetratingintowell
Detecttheproblematicwells,sealofftheproblematicsectionofthewellorreducepumpperformancetolessthanhalfoftheproblematiccapacity.
Contactorsfailtoooften,andmotorsconsumeexcessivekWhperm3pumped.
Highstartingfrequency Reducepumpcapacity,installaVFDorlargertankcapacity.
Powerconsumptionbythemotorisexcessive,andshaft/couplingsplinesweardown.
Upthrust Throttlepumpperformancetoaroundthebestefficiencypointorreducethenumberofimpellersonthepump.
Wornupthrustbearings UpthrustbyON/OFFoperation Establishthenecessaryflowcon-trolatstart-up.
Thrustbearingsoncannedtypemotorsfail
Insulationresistanceonrewind-ablemotorsfails.
Cavitation Removeflowrestrictionstopumpandcheckforperformancearoundthebestefficiencypoint.
Motortemperatureincreasesovertime;pumpperformancefalls.
Deposits(Calcium,Iron,etc)onmo-torsurfaceandinhydraulicpartsofpump.
Pullthepumpandmotorforclean-ing;cleanthepiping,wellfilterandinstallacoolingsleeveonmotor.
Pumpperformancefallsoff Aggressivewater(Corrosionofpumpandpipes)
Pressuretestpipingfromgroundlevel.Ifleakagesoccur,pullandreplacethepumpandpipeswithahighercorrosionclass.
Waterdisappearsdownthepipingwhenthepumpisstopped
Risermainspipecorrosion Pullthepumpandreplacethepip-ingmaterialwithahighercorro-sionclass.
Pumpperformanceistoolow.ThemotorconsumesinsufficientkWh.
Gasevacuation Lowerthepumpwhenequippedwithgasevacuationsleeve.
Thewaterlevelinthewelliscon-stantlybecominglower.
Welloverpumping Reducepumpcapacityuntilthewaterlevelremainsconstantoverthecourseofayear.
Drillmorewellsatotheraquifers.
8 8
10.Accessories
Accessories
10.1 Cooling sleevesIngeneral,coolingsleevesarerecommendedwhenthe motor cooling is insufficient.This is normal intank applications. It can also be necessary in deepwellapplications,wherethereisariskthatthewa-terwillflowtothepumpinletfromaboveandnotautomaticallypassalongthemotor.Other applications where a flow sleeve should beused:• The motor is exposed to a high thermal load,
suchasduetoahighambienttemperature,cur-rentunbalanceoroverload.
• Aggressiveliquidsarepumped,sincecorrosionisdoubledforevery10°Cincreaseintemperature.
• Sedimentationordepositsoccuraroundand/oronthemotor.
Byusingthecoolingsleeves,theflowalongthemo-torwillminimizethemotortemperatureandthere-byextendthemotorlife.
10. Corrosion protection in seawa-ter
Stainlesssteelcanbedamagedbycreviceorpittingcorrosionwhenimmergedintochlorinatedwater.
Thelikelihoodofcorrosiondependson:• Thegradeofmaterialused(GG–AISI304–AISI
316–AISI904L)• Chlorideconcentrationinthewater• Electrochemicalpotentialofthemetalexposed
tomedia• Temperature• Oxygenconcentration• Velocityofthemediaincontactwiththemetal-
licsurface• ThepHvalue.
When metal is submerged into water, it forms anelectrochemicalcell,withananodeandacathodeimmerged into an electrolyte (ex. chlorinated wa-ter).Thisisalsoreferredtoasbeingagalvaniccell.Theanodecanbereferredtoastheactivepartandthecathodeasthenoblepart.
Metals can be listed in order to their relative activ-ity in seawater environment. If the metal surfacebecomestheanode intheelectrochemicalcell, cor-rosiontakesplace.
10..1 Cathodic protectionCathodicprotectionisatechniquetocontrolthecor-rosionofagivenmetalsurfacebypurposelymakingthissurfaceintothecathodeoftheelectrochemicalcell.Thiscanbedoneintwoways:• Galvanic:byuseofsacrificialmetal• Impressed Current: by use of DC power supply
andaninertanode.
10.. Galvanic cathodic protection systems
Fig. 67 Submersible pump set with sacrificial zinc anodes.
8 8
Accessories
Grundfosoffersaseriesofsacrificialzincanodes forthe submersible pump and motor. For metallic riserpipes,standardsolutionsforpipesarerecommended.
The use of sacrificial anodes has an environmentalimpactthatshouldalwaysbetakenintoaccount.Theeffectsofthesaltsbeingformedinthegalvanicproc-essmustalwaysbetakenintoaccount.
The system needs to be monitored in order to findthecorrecttimeforreplacingthesacrificialanodes.
The advantage is that the system is self regulating– the deterioration of the sacrificial anode reflectstheneedsforprotectionofthesystem.
Forbiggerandmorecomplexsystems,engineeringisneededinordertomakethecorrectchoiceconcern-ingcorrosionprotection.Aspectstoconsiderinclude• Materialofsacrificialanode• Shape• Extension• Connection.
10.. Impressed current cathodic protection systems ThisrequiresuseofaDCpowersupplyandknowl-edgeofactualpotentialbetweenthemetalthatneedsprotectionandareferenceelectrode.Itisnecessarytotakeintoaccounttheriskoforganicgrowthonthemetalpartthatovertimecanchangethepotentialdifference.
ThesesystemsrequireindividualdesignandGrund-fos refers to external suppliers of these kinds ofequipment where design and advices can be ob-tained. The normal range of the DC supply will be50Vwith10-100A.
Theadvantageofthismethodisthatitisinert,mean-ing that it does not release any chemical agents totheenvironment.Theprocessrequiresenergyintheformofapowersupply.
4Cl
4e
4CH
O₂ + 2H₂O
2Cl₂
DC power supply
Seawater
Negative return cable(Structure Connection)
ImpressedCurrent Anode
Protectedstructure
InsulatedAnode Cable
Fig. 68 Principle of impressed current cathodic system
10. Drop cablesGrundfos can deliver different drop cable types de-pendingontheapplicationthepumpisgoingtoop-erate in. General guidelines have been described inchapter7.5.
There are cables specially developed to be used inconnectionwithsubmersiblepumps.Severalofthemareapprovedfortransportingdrinkingwater.Numer-ousmanufacturersproducethesecableswhichmaybeusedwithsubmersiblepumps.
A commonly used type is the H07RN-F, which is ageneralpurposecable.Inmostcasesthiscableisad-equateforusewithsubmersiblepumps.Pleasenotethatwaterresistanceoftheconductor insulation isnotalwaysgoodenough.
Grundfos always recommends having the cablemanufacturer guarantee that the cable can fulfilGrundfos standard GS418A0010, which is an ad-ditional insulation resistance test with the cablesubmergedinwater.
Thefunctionalityofthecable isdependantonthewatertight seal. The sealing compound must beable toadhere to thesurfaceof thecableandtheindividualwires.Cleaningofthesurfacebeforethesealingisdoneisthereforevital.Somecablemanu-facturers use fluid lubricants such as silicon oil intheirinternalprocesses.Thesefluidsarealmostim-
Accessories
possibletoremovefromthesurface,makingawa-tertightsealalmostimpossibletocreate.
10. Cable jointsNomatterthetypeofseal,theadhesionbetweenthesealantandthecableisthekeytoawatertightseal.Asstatedunder10.3Dropcables,acleanandoil-freesurfaceonthecableisnecessary.
Solventsmustneverbeapplied,asitmaydamagethecablepermanently.Onlymechanicalcleaningmaybeused,suchasdryingwithacleancloth,orsandpapergrindingtocreateavirginmaterialsurface.
Grundfos offers an approved range of cable joints:both resin type and heat shrink joints.When usinga non-Grundfos joint, we always recommended tomake a ‘soft’ joint, i.e. when using a resin to makethejoint,itmustbeasoftresin.Polyurethaneusuallyfulfilsallrequirementsforawatertightandflexiblejoint.InSection7.6.2describestheprosandconsforthevarioustypesofjoints.
10. Riser pipesGrundfosofferstheWellmaster,aflexibleriserpipe,asanalternativetostandardsteelandplasticpipes.Thisiswovenhosehasapolyurethanelining,isap-provedforuseindrinkingwaterinseveralareas,andcomesinsizesfrom1-8”.Itisavailableinlengthsupto200metres.
Fig. 69 Cross-section of wellmaster hoseWellmaster iseasytohandle,anddoesnottakeup
muchspace.Itswellswhenpressurised,whichmini-misestheeventualgrowthofdepositsontheinnerdiameter. A high pumping efficiency is thereforemaintained.
Wellmaster is primarily used in combination withaggressivewaterasanalternativetostainlesssteelpipes.Someend-usersprefertouseWellmasterinalltheirinstallationsduetotheeaseofinstallationandpulling,andthehighqualityhose.
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11.Additional information
Additional information
For further information about Grundfos, please visit:
www.grundfos.com
Hereyoucanlearnmuchmoreaboutthecompany,ourvaluesandfindtheGrundfosservicecentrenear-est to you. Furthermore you can visit our extensiveproductselectiontoolWebCAPS,whereyoucanfindexactlythepumpyourequire.
WebCAPSWebCAPSisGrundfos’onlineproductselectiontoolthatgivesyoueasyaccesstoawealthof informa-tion.ShortforWeb-basedComputer-AidedProductSelection,theWebCAPSinterfaceiseasytouseandlets you choose between 24 languages for maxi-mum user-friendliness. It includes a full catalogueoftheproductsavailableinyourcountryaswellasaccesstoliterature,CADdrawings–andevenserv-icevideos.
Sizing function that asks all the relevant questionsThesizingfunctionisakeyfeatureofWebCAPS,de-signedtohelpyouselecttherightpumpforthejob.Theprogrammeguidesyoustepbystep,askingforalltherelevantinformation.Ifyouareunsureofspecificfiguresorhowtocalculatethem,simplyclickonthe“calculator” icon.WebCAPSwill thenhelpyoucarryoutallthecalculationsnecessarytoensurethatyougetexactlywhatyouneed.Everyfactorwillbetakenintoaccount,andyouwon’thavetoworkhardtocol-lectinformationfirst.
Replacingapump?Seewhatwewouldrecommend!The “Replacement” function is a clever little fea-ture for anyone about to replace an existing pump– whether it comes from Grundfos or another sup-plier.Here,youcansearchforyourexistingpumpinthedrop-downmenus,applyvariousadditionalcri-teriaifyouwish,andclick“submit”.YouthenhaveacompletelistoftheGrundfospumpswewouldrec-ommendasreplacements.
CAD drawingsThe“CADDrawings”sectionisself-explanatory.Thisis where you go to find CAD drawings of the prod-uctsyouareinterestedin–justnavigatethesimplemenus to download the information you need toyourcomputer.
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Index
Accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 83Additionalinformation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 87Air/gasinwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4 20Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 17Autotransformer–AT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.3 39Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5.1 76Boostermodules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.7 24Cablejoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.4 85Cableselectionandsizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 63Cablesplice/Connectionofmotorcableanddropcable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6.2 65Cablingguidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5.3 77Cathodicprotection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.1 83Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 71CommunicationsandNetworkingTechnology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2 71CommunicationsProtocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4.2 75Coolingsleeves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1 83Corrosionprotectioninseawater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2 83Corrosivewater(seawater). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 22CUEvariblespeeddriveforSPpumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.6 43Currentasymmetry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6 50Deratingofsubmersiblemotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.6 60Dewatering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 19Direct-on-line–DOL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.1 36Dropcables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3 84Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3 48Frequencyconverters(variable-speeddrive). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.6 40Freshwatersupply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1 17Fromfreshwatersources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.1 14Fromtheseaandsaltwatersources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.2 14Functionalprofile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4.3 75Galvaniccathodicprotectionsystems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.2 83Generalintroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1 71Generatoroperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.12 67GENIbus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5 76Gridconnection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5 49Groundwater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 9Groundwaterrequirement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.3 10Groundwaterwells. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.1 9GrundfosGENIbusproductsforSPapplications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.6 78Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6 65Horizontalapplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3 20Hotwaterandgeothermalwater...................................................... 3.6 23Impressedcurrentcathodicprotectionsystems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.3 84Installation&operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 53Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 7Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.1 19Motorcablesandjoints,referencetodropcables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 35Motorprotectiondevices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 36Motortypes,generaldescription . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 33Motorsandcontrols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 33
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Index
Networkingbasics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4 74Networkingtopology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4.1 74No.ofstart/stops. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9 67Operationwithfrequencyconverter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 42Overvoltageandundervoltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.2 47Powergeneration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1 47Powersupply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 47PrimaryResistor-typeStarter,RR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.4 39Protectionagainstboiling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.7 61Pump/motorassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6.1 65Pumpandmotorselection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3 56Pumpcurvesandtolerances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 29Pumpefficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.4 57Pumpprinciple. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1 27Pumpselection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 28Pumpsetting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2 56Pumpstartup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.10 67Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 27Pumpsinparalleloperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.7 66Pumpsinseriesoperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8 66Reducingthelocked-rotorcurrent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 36Requiredraw/wellwaterandwatertreatmentcapacity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.4 11Resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 9Riserpipeconnections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6.3 66Riserpipeselection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4 62Riserpipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.5 85Riverbankfiltration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.2 9SCADAfunctions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3.2 72SCADAmainparts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3.1 72SCADAsystems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3 72Sleevecooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.8 61Softstarter–SS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.5 39Star-delta–SD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.2 38Surfacewater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 14Technicaldescription. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5.2 76Thedutypoint. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.1 56Thefieldbus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4.4 75Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 73Variablefrequencydrives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4 48VFDoperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.11 67Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 47Voltageunbalance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.1 47Watersupply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 9Watertemperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.5 60Wearparts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 28Web-hostedSCADA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3.3 73Welldiameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.2 57Wellyield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.3 57Wellyieldandoperationalefficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.5 12Wellsandwellconditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1 55
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