15.Low Voltage Bulk Metering Equipmant

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Specification

for

LOW VOLTAGE BULK METERING EQUIPMENTSINGLE RATE/TWO RATE

CEB Standard 033 : 1995

CEYLON ELECTRICITY BOARD

No. 50, Sir Chittampalam A. Gardiner Mawatha, Colombo 2.Sri Lanka

Telephone: 24471-8 Telex : 21368 CE Facsimile: 94-1-449572


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CEB STANDARD 033:1995

Amendment Slip No. 1effective from 04-09-96to CEB Standard 033 : 1995

Specification for Low Voltage Bulk MeteringEquipment Single Rate/Two Rate

REVISED TEXTSeptember 1996

1) To add the Clause 5.7 under Basic Features.

Clause 5.7 Manufacturing Experience

The Manufacturer shall have received ISO 9002 Certification for thetype of Meter Offered.

ISO 9002 Quality Assurance System shall be followed in themanufacture of the Meters to be supplied

Bidder shall furnish documentary evidence that he has obtained ISO 9002 Certification,

Offers of Bidders who fail to furnish the proof of ISO 9002 Certification will be rejected.

7.0 INFORMATION TO BE SUPPLIED WITH THE OFFER

To amend the Clause (e) to read as

Bidders shall furnish a minimum of three (3) Performance Certificatesobtained from Electricity Supply Authorities outside the country of theManufacturer to whom the Bidders have supplied Meters of similar typein the past five years.

The certificate shall indicate the type (model) of the Meter, Year of Supply, Quantity Supplied, Percentage of Defective Meters and thePerformance of the Meters based on field experience or field studies.

The purchaser reserves the right to communicate with such Electricity Supply Authorities with regard to the performance of the Meters and theauthenticity of the Performance Certificates issued by them.

CONTENTS

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Page

1. Scope 2

2. System Parameters 2

3. Service Conditions 2

4. Applicable Standards 3

5. Basic Features 3

6. Additional Requirements 7

7. Information to be supplied with the Offer 7

8. Technical Literature and Drawings 8

9. Inspection and Testing 8

10. Sample Study 9

11. Annexure 9

SPECIFICATION FOR LOW VOLTAGE BULK METERING EQUIPMENTSINGLE RATE/TWO RATE

1.0 SCOPE

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This Specification covers the manufacture and testing of the following Low VoltageBulk Metering Equipment. The Metering Equipment shall be suitable for 3 phase 4 Wire50 Hz.system and for operation of unbalanced load.

a) 3 Phase 4 Wire kWh Meter with single register

b) 3 Phase 4 Wire kWh Meters with double register

c) 3 Phase 4 Wire kVAh Meter with kVA Maximum Demand Indicator

d) Single Phase current transformers to match the above meters, if the meters areC.T. operated.

e) Adjustable time switch to be used with the 2 Rate kWh Meter for registeringkWh consumption during peak hours and off peak hours separately.

2.0 SYSTEM PARAMETERS

Nominal Voltage - 400/230V A.C. 3 Phase and Neutral

System Highest Voltage - 440V. A.C. 3 Phase and Neutral

System Frequency - 50 Hz.

Neutral Earthing - Neutral Solidly earthed at S/s.

System Fault Level - 25 k.A.

3.0 SERVICE CONDITIONS

Annual average AmbientTemperature - 30 C

Maximum Ambient air Temperature - 40 C

Minimum Ambient air Temperature - 15 C

Average Relative Humidity fromM.S.L. to (1500 Meters) - 90%

Environmental condition - Humid tropical climate with heavilypolluted atmosphere.

Operational altitude - Up to 1900m above MSl

4.0 APPLICABLE STANDARD

The equipment and components supplied shall be in accordance with the latesteditions /amendments of the Standards specified below.

IEC 521 (1988)

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BS 5685 (1979 / 1985)Part 1 - Electricity meters - Class 0.5, 1 and 2

single and poly phase, single rate andmulti-rate watt-hour meters.

IEC 211BS 5685 Part 3 (1985) - Meters having Class 1 electro mechanical

maximum demand indicators

Part 5 (1987) - Time switch

BS 3938 (1972/1983) - Current transformer

5.0 BASIC FEATURES

5.1 General requirements for

a) 3 Phase 4 Wire kWh Meter with single /double register b) 3 Phase 4 Wire kVAh Meter with kVA Maximum Demand Indicator c) Adjustable time switch to be used with the Two Rate kWh Meter

5.1.1 The equipment shall be dust-proof and suitable for use under tropical conditionsstipulated in Clause 3.0 above. They are to be used in heavily pollutedatmosphere.

5.1.2 The equipment shall have a separate cover for the terminal block in addition tothe main equipment cover. Provision shall be made to seal the equipment cover and the terminal cover separately.

If the cover is of non-transparent material a glass window shall be provided to

facilitate reading of the register and observation of the rotor. The window shallbe securely bonded to prevent the dislocation by use of force from out-side.

If the equipment cover is of transparent material, no separate window for reading is required.

5.1.3 The equipment shall have bottom terminals. The terminal cover shall be of insulating material and shall be of the extended type. The terminal covers shallbe provided with easily breakable knockouts for the entry of service wires.

5.1.4 The design and manufacture of the equipment shall be such that the equipmentoperates within stipulated error limit for the respective class of the equipmentfor a period of at least 15 years without requiring re-calibration or overhauling.

5.1.5 The design should incorporate suitable means of adjustment for low loads, fullloads and inductive load. The minimum range of adjustments shall be inaccordance with the BS 5685 (1985), table 19.

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5.3.2 The kWh Meters shall be of single rate / two rate type. In the case of two ratemeters the two registers shall be independent from each other and be marked"Normal" and "Peak". The register marked "Normal" shall be registeringnormally and it should be possible to stop this and to activate the register marked "Peak" with an external voltage signal of 240V from the time switch.The activating coil shall be capable of continuous operation.

5.3.3 The Meters shall be fitted with jumping figure cyclometer registers and at leastsix number drums for each register. For single register Meters size of register figures shall be above 7mm.

5.3.4 The Meter Constant shall be embossed on the body of the register to facilitateidentification when carrying out repairs.

5.4 Special Design Requirements for kVA Maximum Demand IndicatingMeters (MDI)

5.4.1 The maximum demand indicating Meter shall be either restricted power factor range type or full power factor range type as indicated below and in theSchedule of Prices.

i) Restricted Power Factor Range type MDI Meters

Electro-mechanical design (Merz Type) /Electronic type of restrictedpower factor range type, and suitable for correct operation within thepower factor range of 0.69 lagging to 0.97 lagging on unbalanced loads.

ii) Full Power Factor Range type MDI Meters

Electro-mechanical design (Merz Type) /Electronic type suitable for correct operations for the full power factor range (0 to 360 ) on

unbalanced loads.

5.4.2 The Meter shall be capable of indicating the maximum of average kVA demandover a demand integration period of fifteen (15) minutes. MDI shall be of accuracy Class 2.

5.4.3 The Meter shall be incorporated with an internal timing element to reset thedemand integration period at the end of each 15 minute interval and this shallbe operated by a synchronous motor. The time lapsed in the integrating periodshall be indicated.

5.4.4 The full range of the dial of the MDI shall be used to indicate the rated kVA plusthe permitted over load.

5.4.5 An external manual device shall be provided for resetting the maximumdemand indicator. This shall be a press button or such similar simple methodhaving facilities for sealing separately.

5.5 Design requirements for Time Switch

5.5.1 The time switch required shall be operated by a time clock having either

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a) A Synchronous drive rated at 240V, 50 Hz. together with the spring reserve toensure operation of the time switch for at least 48 hours continuouslyduring a supply failure. This spring shall be automatically rechargedwhen supply (240 V, 50 Hz.) is restored.

b) Quartz Oscillator drive operated by a rechargeable battery back-up to ensureoperation of the time switch for at least 48 hours continuously during asupply failure. This battery shall be recharged through a built in charger when the supply of 240V, 50 Hz is restored. The life time of thisrechargeable battery shall be at least 10 years.

5.5.2 The make and break times of the switch shall be independently adjustable.The contact ratings shall match the requirements of the meter and shall

operate satisfactorily for at least 20 years. Provision shall be made for sealing the time switch.

5.5.3 The time of day and the switching time settings of individual switches shallbe clearly visible for purpose of setting and checking.

5.5.4 The Time Switch is to be used in association with the two rate meter sets togive the external signal to activate the "Peak" register.

5.5.5 Time switches shall be rated at 230 V, 50 Hz. and be capable of withstanding amaximum working voltage of 250V.

5.5.6 The make (On) and break (Off) times of the switch shall be independentlyadjustable. The time of day and the switching time settings of the switch shallbe clearly marked and visible for purposes of resetting and checking. The dialof the device shall be for 24 hours. The minimum setting period possible

between operations shall not be more than one hour.5.5.6 If facilities are provided to test the operation of the contacts they shall have

proper sealing facilities to avoid malpractice.

5.6 Design Requirements for Current Transformer

5.6.1 The Current Transformer shall be single phase, ring type to match the abovemeters and complying with B.S. 3938.

5.6.2 These shall be suitable for use on 400 Volt, 50 Hertz, 3 Phase, 4 Wire systemand shall have an Insulation level of 2 kV and a rated burden of 15 VA eachand be of accuracy class 1.0.

5.6.3 The secondary terminals shall be provided with the bolts, nuts and washersrequired for connecting the wires.

6.0 ADDITIONAL REQUIREMENTS

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The equipment supplied under this specification shall be reliable, of ruggedconstruction and of a proven design.

6.1 Rating Plate Marking s

6.1.1 The words "Property of the Ceylon Electricity Board" shall be engraved on thename plate.

6.1.2 A serial number (which will be indicated at the time of placing an order) shallalso be engraved on the name plate.

6.1.3 The standard information stipulated in the standard specified including theassociated CT ratio shall be indicated in the name plate.

6.2 Service and Tools

6.2.1 A list of spare parts and tools if supplied with the equipment shall be furnishedwith the offer.

6.2.2 In addition, the prices of a recommended set of spares and special toolsnecessary for 10 years of operation shall be quoted separately (item wise).

6.3 Packing

All items shall be packed in a manner to prevent damage due to rough handling andeach packing shall indicate the Type, Rating and Serial No. of the item.

7.0 INFORMATION TO BE SUPPLIED WITH THE OFFER

The following shall be furnished with the offer.(a) Catalogues describing the equipment and indicating the model number.

(b) Literature describing the operational feature of the equipment.

(c) Constructional features, materials used for components and relevant technicalliterature.

(d) Complete dimensional drawings.

(e) Performance certificates from five electricity supply authorities to whom similar equipment have been supplied within the last five years. The certificates shallstate that the performance of the equipment based on the field experience hasbeen satisfactory.

(f) The details of the information that will be indicated on the Name Plate of theequipment.

(g) Completed Schedule of Particulars.

(h) Type Test Certificates

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The Test Certificates, Performance Curve, Tables etc. of the Type Testperformed conforming to the standard specified. The Type Test shall beperformed at a reference voltage of 440 V line to line at a reference frequencyof 50 Hz. and at a reference temperature. The test certificates shall clearlyidentify the equipment concerned, showing the manufacturer's identity, ref. no.and basic parameters, and shall be from an independent testing authorityacceptable to the Purchaser.

Failure to furnish these particulars will result in the offer being rejected.

8.0 TECHNICAL LITERATURE AND DRAWINGS

Technical Literature in English language on the installation, operation and maintenanceshall be supplied with each set of equipment and they shall be descriptive and self explanatory, complete with necessary diagrams and drawings.

9.0 INSPECTION AND TESTING

9.1 Inspection

The selected Bidder shall make necessary arrangements for inspection by arepresentative of the Purchaser and to carry out in his presence necessary routinetests of the equipment offered.

9.2 Routine / Sample Test

The following test as per relevant Standard shall be witnessed by the representative of the Purchaser and the Test Certificates will form a part of the shipping documents.

Extra copies of these Test Certificates shall also be supplied with the equipment.

(a) Clearance and creepage distances

(b) Power loss

(c) Apparent power loss

(d) Heating

(e) AC voltage test

(f) Flammability test

(g) Variation due to self-heating

(h) Percentage error limits

Each consignment of equipment shall accompany one set of test results recorded intabular form to conform to the above. If the test results are recorded in separate sheetsall such sheets pertaining to each consignment shall be bound together as one volume.

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10.0 SAMPLE STUDY

One sample of each item with manufacturer's seals shall be handed over to thePurchaser before the date of closing of tender. They will be returned to theunsuccessful tenderer after decision is made on the offer. The samples furnished bythe successful tenderer will be retained and set off against the quantities to be suppliedunder the main award.

11.0 ANNEXURE

Schedule of Particulars

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Annexure - A

SCHEDULE OF PARTICULARS(To be filled by the Bidder)

1. Class of Meter :

2. Type No. :

3. Basic Current (I b) :

4. Rated Maximum Current Imax :

5. Starting Current :

6. Rated Voltage :

7. Frequency :

8. Power loss :

9. Apparent Power Loss :

10. Temperature Rise

(a) windings :(b) external surfaces of the case :

11. Material of Cover, Baseand the Terminal Block :

12. Maximum Withstand Temperature of

(a) terminal block :(b) terminal cover and meter case :

13. Type of Register :

14. Impulse Withstand Voltage :

15. AC Withstand Voltage :

16. Percentage error limits with

(a) balance loads :

(i) at 0.05 I b and unity p.f. :

(ii) from 0.1 I b to Imax unity p.f. :

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(iii) at 0.1 I max :

a) 0.5 lagging :b) 0.8 leading :

(iv) From 0.2 I b to Imax

a) 0.5 lagging :b) 0.8 leading :

(b) Single phase load

(i) from 0.2 I b to Ib at unity p.f. :

(ii) at 0.5 I b and 0.5 lagging :

(iii)at Ib4 and 0.5 lagging :

(iv) from I b to Imax and unity p.f. :

17. Limits of Variations (in % of error)due to short-time over Currents at BasicCurrent and Unity p.f. :

18. Limits of Variations (in % of error)due to Self-heating at I max.

(i) at unity p.f. :(ii) at 0.5 lagging :

19. Starting Current (% of basic current)at Unity p.f. :

20. Minimum Range of Adjustment(of rotation speed of the rotor in %)

(i) Breaking Element (0.5 I max )and unity p.f. :

(ii) Low load (0.5 I b and unity p.f. :

(iii) Inductive load :

(a) (0.5 I b) 0.5 lagging :(b) (0.5 I max ) 0.5 lagging :

21. Any deviation from this Specification(indicate the relevant Clause Nos.) :

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Annexure - B

SCHEDULE OF PARTICULARS TO BE COMPLETED BY THE BIDDER

1. Circuit System -

2. Class of Meter -

3. Reference Voltage -

4. Reference Frequency -

5. Basic Current I t -

6. Rated Maximum Current Imax -

7. Starting Current -

8. Reference Temperature -

9. Standards Conformed to -

10. Meter Constant -

11. Basic Speed -

12. Basic Torque -

13. Rotor Weight -

14. Limits of Errors -

15. Insulation -Withstanding Voltage for 1 Min -Insulation resistance -

16. Power Losses -

Voltage circuit at reference voltage -Current circuits at basic current -

17. Type of rotor bearings -

18. Type of Register -Number of digits/Indication -Size of digits -

19. Type of Meter Base -Type of Meter Cover -Colour of Case -

bulkmete.rs.33

15.Low Voltage Bulk Metering Equipmant

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