7154 VFD7154 VFDPresentation #5Presentation #5

June 2002June 2002

Paul WeingartnerPaul Weingartner

Application of VFDsApplication of VFDs

VFDs applied for energy savingsVFDs applied for energy savings

http://www.achrnews.com/CDA/ArticleInforhttp://www.achrnews.com/CDA/ArticleInformation/features/BNP__Features__Item/0,mation/features/BNP__Features__Item/0,1338,73944,00.html1338,73944,00.htmlIn the hvac industry, vfd’s are usually In the hvac industry, vfd’s are usually found on motors that drive fans, blowers, found on motors that drive fans, blowers, pumps, cooling towers, etc. The pumps, cooling towers, etc. The Department of Energy reports that 64% of Department of Energy reports that 64% of all electrical energy in the U.S. is all electrical energy in the U.S. is consumed by electric motors. consumed by electric motors.

Typical energy savingsTypical energy savings

According to some studies, the addition of According to some studies, the addition of vfd’s to an existing system can result in a vfd’s to an existing system can result in a reduction in energy consumption of 30% to reduction in energy consumption of 30% to 60%. 60%.

ASHRAE Standard 90.1 will effectively ASHRAE Standard 90.1 will effectively require vfd’s on every hvac motor except require vfd’s on every hvac motor except the smallest ones in commercial buildings the smallest ones in commercial buildings of more than 25,000 sq ft. of more than 25,000 sq ft.

Water pumping exampleWater pumping example

With a 25hp motor running 23 hours per day (2 hours at 100 percent speed; 8 hours at 75 percent; 8 hours at 67 percent; 5 hours at 50 percent, which is typical of the water supply industry) a VFD can reduce energy use by 45 percent.At 10 cents/ kWh, this results in an annual savings of $5,374. Source: CEC, 1999

http://www.cee1.org/ind/mot-sys/Water_Pump_Bro.pdf

Comparison of valve vs. VFD pump

Observation

If the rate of electricity is $0.02 per KWHr, the chances are slim that you’ll be able to cost justify a Variable Frequency Drive for your system. However, if the electricity rate is $0.05 per KWHr or higher, you can expect to show fast paybacks for virtually any system.

How is the current system being How is the current system being usedused

The The Duty CycleDuty Cycle of your system (where the of your system (where the system operates and for how long) will also system operates and for how long) will also affect potential savings. If, for instance, the affect potential savings. If, for instance, the system tends to operate close to the system tends to operate close to the Design Design PointPoint for the majority of the time, the savings for the majority of the time, the savings potential through speed control is limited. On potential through speed control is limited. On the other hand, if the system is operating at the other hand, if the system is operating at reduced flows for extended periods of time, the reduced flows for extended periods of time, the potential savings by using VFD’s is great.  potential savings by using VFD’s is great.  http://www.usdrivesinc.com/payback.htmhttp://www.usdrivesinc.com/payback.htm

Cost savings tableCost savings table

Centrifugal pumpCentrifugal pump

MoneyMoney

A penny saved in NOT equal to a penny A penny saved in NOT equal to a penny earned!! For commercial businesses, a earned!! For commercial businesses, a penny saved is equal to 20 pennies penny saved is equal to 20 pennies earned (revenue) because the net income earned (revenue) because the net income approximates to 5% of the revenue.approximates to 5% of the revenue. http://www.unicade.com/Articles/ACEEE99.hthttp://www.unicade.com/Articles/ACEEE99.ht

mm

PaybackPayback

Not this kind of PaybackNot this kind of Payback

http://us.imdb.com/Title?0120784http://us.imdb.com/Title?0120784

PaybackPayback

http://www.usmotors.com/Datasheets/pds544-196.htmhttp://www.usmotors.com/Datasheets/pds544-196.htm

Using energy eff motorUsing energy eff motor

S = 0.746 x HP x C x N [ 100/SE - 100/PE ]S = 0.746 x HP x C x N [ 100/SE - 100/PE ]

S = Energy Savings per year @ 100% loadS = Energy Savings per year @ 100% loadC = Energy Costs $ per kilowatt hour (KWH)C = Energy Costs $ per kilowatt hour (KWH)N = Hours per year running timeN = Hours per year running timeSE = Standard efficiency product at full loadSE = Standard efficiency product at full loadPE = Premium efficiency product at full loadPE = Premium efficiency product at full load

Device NetDevice Net

Standards based protocolStandards based protocol

Must supply external 24VDC to networkMust supply external 24VDC to network

Typical devicesTypical devices VFDVFD PLCPLC DisplaysDisplays Push buttonsPush buttons PhotoeyesPhotoeyes Motor startersMotor starters

DevicesDevices

Each device on the network is a “node”Each device on the network is a “node”Max of 64 nodes (0-63)Max of 64 nodes (0-63)Each device must be “commisioned” Each device must be “commisioned” before use.before use. The default address is 63 and should be The default address is 63 and should be

changed in configurationchanged in configuration

Each node must be uniqueEach node must be unique Can’t have two nodes both with the same Can’t have two nodes both with the same

addressaddress

RS NetworxRS NetworxWith RSNetWorx Software for DeviceNet Network you With RSNetWorx Software for DeviceNet Network you can:can:

Define the devices that are present on your network. You Define the devices that are present on your network. You can either manually drag/drop devices/modules or go can either manually drag/drop devices/modules or go online to a DeviceNet network and let the software online to a DeviceNet network and let the software determine the devices/modules that are present.determine the devices/modules that are present.

Define configuration settings for devices on the Define configuration settings for devices on the DeviceNet network through a convenient property page DeviceNet network through a convenient property page interface.interface.

Define the input/output information exchanges that you Define the input/output information exchanges that you want to take place on the DeviceNet network.want to take place on the DeviceNet network.

DeviceNet featuresDeviceNet features

Low Cost (Based on low cost CAN chip). Low Cost (Based on low cost CAN chip). High Speed. It supports 3 baud rates: 125Kbps, High Speed. It supports 3 baud rates: 125Kbps, 250Kbps and 500 Kbps which is believed to meet 95% of 250Kbps and 500 Kbps which is believed to meet 95% of the industrial requirement. the industrial requirement. Reliable. It uses the well proven CAN protocol Reliable. It uses the well proven CAN protocol incinerates with the application layers that has incinerates with the application layers that has undergone strict conformance testing to ensure the undergone strict conformance testing to ensure the reliability. reliability. Support up to 64 active nodes. In theory, the node can Support up to 64 active nodes. In theory, the node can be expended by using bridge system (such as CAN/CAN be expended by using bridge system (such as CAN/CAN bridge or other gateway). bridge or other gateway). Easy installation. Virtually "Plug-and-Play". Easy installation. Virtually "Plug-and-Play".

http://www.warwick.ac.uk/devicenet/devicenet_faq.htmhttp://www.warwick.ac.uk/devicenet/devicenet_faq.htm

Cable lengthsCable lengths

PLC DeviceNetPLC DeviceNet

Accomplished with a DeviceNet Scanner Accomplished with a DeviceNet Scanner cardcard

1747-SDN (for SLC500 family)1747-SDN (for SLC500 family)

Plugs into standard slotPlugs into standard slot

Takes 32 words of memoryTakes 32 words of memory 1 word = 16 bits = 2 bytes1 word = 16 bits = 2 bytes

PLC SDN module displayPLC SDN module display

Shows both error codes and current Shows both error codes and current operating infooperating info

Code 92 = no powerCode 92 = no power

Code 80 = idle modeCode 80 = idle mode

Will show its node addressWill show its node address

CommunicationCommunication

Using a tool such as RS Networx, each Using a tool such as RS Networx, each device must be given:device must be given: Node addressNode address Told whether it is a master or a slave deviceTold whether it is a master or a slave device Told what info to share and who to share it Told what info to share and who to share it

withwith

DeviceNet settingsDeviceNet settings

Node addressNode address

Baud rate (125, 250, 500kb/sec)Baud rate (125, 250, 500kb/sec)

Master/slaveMaster/slave

Channel dataChannel data

Destination node addressDestination node address

Masking (* careful on Powerflex drives)Masking (* careful on Powerflex drives)

TroubleshootingTroubleshooting

Always, without exception Always, without exception cycle powercycle power on all devices on all devices after configuration changes after configuration changes in networked systemsin networked systems

Troubleshooting 2Troubleshooting 2

Look for the error codesLook for the error codes

Always backup and grab baseline data Always backup and grab baseline data before making changesbefore making changes

Check LED status indicatorsCheck LED status indicators

PLC SDN examplePLC SDN example

PLC addressingPLC addressing O: is the fileO: is the file O:2 is the slotO:2 is the slot O:2.1 is the wordO:2.1 is the word O:2.1/5 is the bitO:2.1/5 is the bit

Numbering starts at zeroNumbering starts at zero

ExampleExample

If the SDN module is in slot 2 of the PLCIf the SDN module is in slot 2 of the PLC O:2.0/0 is the run bit for the DeviceNet O:2.0/0 is the run bit for the DeviceNet

modulemodule O:2.1 is the Command wordO:2.1 is the Command word I:2.1 is the Status wordI:2.1 is the Status word

Command word (bit – function)Command word (bit – function)

0= Stop0= Stop

1= Start1= Start

4= Direction4= Direction

Status word (bit – function)Status word (bit – function)

0 = Ready0 = Ready

2 = Command direction2 = Command direction

3 = Actual direction3 = Actual direction

4= Accelerating (1=yes)4= Accelerating (1=yes)

5 = Deaccelerating (1=yes)5 = Deaccelerating (1=yes)

6 = Alarm6 = Alarm

7 = Fault7 = Fault

Powerflex DeviceNetPowerflex DeviceNet

By default 2 words are passed backBy default 2 words are passed back Status wordStatus word Speed settingSpeed setting

Can be configured to send back any Can be configured to send back any parameter of interestparameter of interest

Parameters are referenced starting above Parameters are referenced starting above #379 (the last Powerflex parameter)#379 (the last Powerflex parameter)

Simple programSimple program

Tools needed for DeviceNet Tools needed for DeviceNet systemssystems

RS Networx for DeviceNETRS Networx for DeviceNET Careful – they sell another version for Control Careful – they sell another version for Control

LogixLogix

Protocol converter or protocol gatewayProtocol converter or protocol gateway

PCPC

RS Linx (Lite will work)RS Linx (Lite will work)

RS LinxRS Linx

Communication gateway for RS software Communication gateway for RS software and the PLC, VFD, Displaysand the PLC, VFD, Displays

You have to see the devices on the net You have to see the devices on the net with RS Linx first. Else….with RS Linx first. Else….

RS Linx versionsRS Linx versions

Lite – ships with PLC softwareLite – ships with PLC software

OEM, Gateway – can be used to connect OEM, Gateway – can be used to connect to Active-X compliant systemsto Active-X compliant systems

What can you do with this stuffWhat can you do with this stuff

WebWeb

ExcelExcel

RS Drive ToolsRS Drive Tools

Ability to backup configuration of drivesAbility to backup configuration of drives

Clone drive setupsClone drive setups

Advanced tools – analysisAdvanced tools – analysis Not for average userNot for average user