Power Measurement 3720 ACM User manual

Installation
& Operation
Manual
3720 ACM
CONTENTS
Advanced Digital Power
Instrumentation Package
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Power Measurement 3720 ACM Installation and Operation Manual
Danger
During normal operation of this device, hazardous voltages are present which
can cause severe injury or death. These voltages are present on the terminal
strips of the device and throughout the connected potential transformer (PT),
current transformer (CT), status input, relay, and control power circuits. Installa-
tion and servicing should be performed only by qualified, properly trained
personnel. See Chapter 2: Installation for additional warnings.
Warning
This equipment generates, uses, and can radiate radio frequency energy and if
not installed and used in accordance with the instructions manual, may cause
interference to radio communications. It has been tested and found to comply
with the limits for a Class A computing device pursuant to Part 15 of FCC Rules,
which are designed to provide reasonable protection against such interference
when operated in a commercial environment. Operation of this equipment in a
residential area may cause interference in which case the operator will be
required to take whatever measures may be required to correct the interference.
Limitation of Liability
Power Measurement Limited reserves the right to make changes in the devices
or the device specifications identified in this Installation and Operation Manual
without notice. Power Measurement Limited advises customers to obtain the
latest version of device specifications before placing orders to verify that the
information being relied upon by the customer is current.
In the absence of written agreement to the contrary Power Measurement
Limited assumes no liability for Power Measurement Limited applications
assistance, customer’s system design, or infringement of patents or copyrights of
third parties by or arising from the use of devices described herein. Nor does
Power Measurement Limited warrant or represent that any license, either
expressed or implied, is granted under any patent right, copyright, or other
intellectual property right of Power Measurement Limited covering or relating
to any combination, machine, or process in which such device might be used.
EXCEPT TO THE EXTENT PROHIBITED BY APPLICABLE LAW, UNDER NO
CIRCUMSTANCESSHALLPOWERMEASUREMENTLIMITEDBELIABLEFOR
CONSEQUENTIALDAMAGESSUSTAINEDINCONNECTIONWITH SAID
PRODUCTANDPOWERMEASUREMENTLIMITEDNEITHERASSUMESNOR
AUTHORIZES ANY REPRESENTATIVE OR OTHER PERSON TO ASSUME FOR
IT ANY OBLIGATION OR LIABILITY OTHER THAN SUCH AS IS EXPRESSLY
SET FORTH HEREIN.
3720 ACM is a trade mark of Power Measurement Limited. Other brands and
their products are trade marks of their respective holders and should be noted as
such.
© 1999 Power Measurement Ltd.
The information contained in this document is believed to be
accurate at the time of publication, however, Power Measurement
Ltd. assumes no responsibility for any errors which may appear
here and reserves the right to make changes without notice.
TollFree
1-877-METER-IT
(1-877-638-3748)
World-Wide Web www.pml.com
WorldwideHeadquarters
POWER MEASUREMENT LTD.
2195 Keating Cross Road,
Saanichton, BC,
Canada V8M 2A5
Tel:[phone]
Fax:[phone]
Europe & Middle East
POWER MEASUREMENT EUROPE
Zaventem Business Park, Ikaroslaan 5,
B-1930 Zaventem
(Brussels), Belgium
Tel:[phone]
Fax:[phone]
Asia & Pacific
POWER MEASUREMENT
AUSTRALIA
7/16 Ledgar Road,
Balcatta, Perth
Western Australia 6021
Tel:[phone]
Fax:[phone]
Revision Date: March 24, 1999
© 1999 Power Measurement Ltd.
All rights reserved
Printed in Canada
70000-0004
For further information or technical assistance, please
contact your local Power Measurement representative,
or Customer Service at one of the following locations:
ISO 9002-94
Registration
Cert # 002188
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Power Measurement 3720 ACM Installation and Operation Manual
Throughout this operation manual, the following methods are used to highlight important
information:
NOTE
Describes important considerations related to a device setup, feature or application.
CAUTION
Alerts you to a condition which could potentially cause damage to the device or other external
equipment.
WARNING or DANGER
Warns you to avoid conditions that could potentially cause serious personal injury and/or
equipment damage.
Wiring diagrams and labels use symbols to denote the following objects:
Fuse
Potential Transformer (PT)
Current Transformer (CT)
Switchgear chassis (Earth) ground
Alternating current
Direct current
3
Three-phase alternating current
Protective conductor termainal
This device has a display timeout feature which automatically turns off the front panel display
after a programmable timeout period. When the device is shipped, this timeout period is preset
to 180 minutes (3 hours). Following a display timeout, you can turn the display back on by
pressing any button on the front panel.
CONVENTIONS
DISPLAY TIMEOUT
SYMBOLS
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Power Measurement 3720 ACM Installation and Operation Manual
Table of Contents
1 INTRODUCTION
2 INSTALLATION
2.1 Location&Mounting................................................................................................2-1
2.2 GeneralWiringConsiderations ................................................................................2-2
2.3 PowerSupplyConnections......................................................................................2-2
2.4 ChassisGroundConnection .................................................................................... 2-2
2.5 PhaseVoltageandPhaseCurrentInput Connections .............................................2-3
2.5.1 PhaseVoltage Inputs ..............................................................................2-3
2.5.2 PhaseCurrentInputs...............................................................................2-3
2.5.3 PT & CT Connection ...............................................................................2-4
2.5.4 VoltageReferenceConnection ................................................................ 2-4
2.5.5 WaveformCaptureConnections ..............................................................2-5
2.5.6 I4 CurrentInputConnections...................................................................2-5
2.5.7 Connection for Three Phase WYE(Star) Systems ...................................2-6
2.5.8 Connection for Three Phase Delta Systems ...........................................2-9
2.5.9 Connection for Single Phase Systems .................................................. 2-11
2.6 CommunicationsConnections ............................................................................... 2-12
2.6.1 Introduction ........................................................................................... 2-12
2.6.2 ISOCOM2CommunicationsCard.......................................................... 2-12
2.6.3.a MultiportCommunicationsCard(MPCC) ............................................... 2-14
2.6.3.b MultiportCommunicationsCardwithEthernet(MPE)............................ 2-15
2.6.4 RS-232Connections.............................................................................. 2-17
2.6.5 RS-485Connections.............................................................................. 2-19
2.6.6 MultiportConnections............................................................................2-23
2.7 ControlRelayConnections .................................................................................... 2-24
2.7.1 RelayApplicationPrecautions...............................................................2-25
2.7.2 Form-CRelays ...................................................................................... 2-25
2.7.3 Solid State Relays................................................................................. 2-26
2.8 StatusInputConnections ......................................................................................2-27
2.9 AuxiliaryVoltageInputConnections ...................................................................... 2-28
2.10 AuxiliaryCurrentOutputConnections.....................................................................2-29
2.11 Maintenance.......................................................................................................... 2-29
2.11.1 BatteryReplacement ............................................................................. 2-29
2.11.2 DisplayRestore ..................................................................................... 2-29
2.12 FieldServiceConsiderations .................................................................................2-30
3 GENERALOPERATION
3.1 Introduction .............................................................................................................3-1
3.2 PowerUp.................................................................................................................3-1
3.3 DisplayMode ..........................................................................................................3-1
3.3.1 FrontPanel Display .................................................................................3-1
3.3.2 FrontPanelButtons ................................................................................3-3
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Power Measurement 3720 ACM Installation and Operation Manual
Table of Contents
3.4 FieldProgramming ..................................................................................................3-6
3.4.1 Introduction .............................................................................................3-6
3.4.2 EnteringProgrammingMode ...................................................................3-6
3.4.3 ProgrammingButtonFunctions ...............................................................3-6
3.4.4 EnteringandChangingthePassword ......................................................3-6
3.4.5 AccessingandModifying Parameters .....................................................3-6
3.4.6 OperatingParameterDescriptions...........................................................3-7
3.5 Setting the Volts Scale, Amps Scale, I4 Scale, Volts Mode, and Standard Freq..3-20
3.6 DisplayFormat ...................................................................................................... 3-21
3.7 ControlRelayOperation......................................................................................... 3-21
3.8 StatusInputOperation ..........................................................................................3-22
3.9 AuxiliaryVoltageInputOperation ..........................................................................3-23
3.10 AuxiliaryCurrentOutputOperation ........................................................................3-24
3.11 Daylight Savings Time .......................................................................................... 3-24
4 MEASUREDPARAMETERSANDSTATUSINFORMATION
4.1 Introduction .............................................................................................................4-1
4.2 High-SpeedMeasurements......................................................................................4-2
4.3 Real-TimeMeasurements........................................................................................4-2
4.3.1 BaseMeasurements ...............................................................................4-2
4.3.2 MeasurementModes...............................................................................4-4
4.4 Energy .....................................................................................................................4-7
4.4.1 BaseMeasurements ...............................................................................4-7
4.4.2 MeasurementModes...............................................................................4-7
4.4.3 ResettingtheEnergyCounters................................................................4-7
4.5 PowerReadingPolarities.........................................................................................4-8
4.6 StatusInformation ...................................................................................................4-9
4.6.1 Relays, Status Inputs & Setpoints ..........................................................4-9
4.6.2 DiagnosticsParameters ..........................................................................4-9
5 TIME-OF-USESYSTEM
5.1 Introduction .............................................................................................................5-1
5.2 Programming ...........................................................................................................5-1
5.2.1 WinTOUSetup ........................................................................................ 5-1
5.2.2 Calendar ..................................................................................................5-1
5.2.3 Profiles ....................................................................................................5-1
5.2.4 Tariffs......................................................................................................5-1
5.2.5 EnergyRegisters.....................................................................................5-1
5.2.6 DemandRegisters...................................................................................5-2
5.2.7 StatusParameters ..................................................................................5-2
5.3 Access to TOU Data ...............................................................................................5-2
5.3.1 ReadingTOUData ..................................................................................5-2
5.3.2 UsingTOUDataasTriggerParameters ..................................................5-2
5.3.3 ResettingtheTOURegisters...................................................................5-2
5.4 Calculation of Energy Costs ....................................................................................5-2
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Power Measurement 3720 ACM Installation and Operation Manual
Table of Contents
6 SETPOINT SYSTEM
6.1 Introduction .............................................................................................................6-1
6.2 Setpoint Types ........................................................................................................6-3
6.2.1 Introduction .............................................................................................6-3
6.2.2 SetpointResponseTimes .......................................................................6-3
6.2.3 High-SpeedSetpoints..............................................................................6-3
6.2.4 StandardSetpoints..................................................................................6-3
6.3 TriggerParameters ..................................................................................................6-3
6.3.1 Introduction .............................................................................................6-3
6.3.2 Over & Under Setpoints with Time Delays ..............................................6-5
6.3.3 On/Off & Counter Setpoints ....................................................................6-7
6.3.4 Time-OvercurrentCurve ..........................................................................6-7
6.4 Setpoint Actions...................................................................................................... 6-8
6.4.1 Introduction .............................................................................................6-8
6.4.2 RelayControl...........................................................................................6-9
6.4.3 WaveformCaptureTriggering .................................................................. 6-9
6.4.4 WaveformRecorderTriggering .............................................................. 6-10
6.4.5 SnapshotLogTriggering........................................................................ 6-10
6.4.6 ClearingFunctions................................................................................. 6-10
6.5 ProgrammingSetpoints ......................................................................................... 6-11
6.6 PowerOutages......................................................................................................6-12
7 WAVEFORMCAPTURE&RECORDING
7.1 Introduction .............................................................................................................7-1
7.2 WaveformCapture...................................................................................................7-1
7.2.1 TheImportance of PowerQualityMonitoring...........................................7-1
7.2.2 UsingCapturedData ...............................................................................7-1
7.2.3 TriggeringfromaSetpoint .......................................................................7-1
7.2.4 TriggeringManuallyviaCommunications ................................................7-2
7.3 WaveformRecording ...............................................................................................7-3
7.3.1 UsingRecordedData...............................................................................7-3
7.3.2 ConfiguringtheRecorder .........................................................................7-3
7.3.3 TriggeringfromaSetpoint .......................................................................7-4
7.3.4 Adjusting the Trigger Point ...................................................................... 7-4
7.3.5 TriggeringManuallyviaCommunications ................................................7-6
8 ON-BOARDDATALOGGING
8.1 Introduction .............................................................................................................8-1
8.2 Event Log................................................................................................................8-1
8.3 Minimum / Maximum Logs ......................................................................................8-3
8.3.1 Preset Min/Max Log ................................................................................ 8-3
8.3.2 ProgrammableMin/MaxLogs..................................................................8-4
8.3.3 Resetting the Min/Max Logs....................................................................8-4
8.4 ProgrammableSnapshotLogs ................................................................................8-5
8.4.1 Introduction .............................................................................................8-5
8.4.2 MemoryAllocation...................................................................................8-5
8.4.3 StandardSnapshotLogs .........................................................................8-6
8.4.4 High-SpeedSnapshotLog .......................................................................8-8
8.5 Access to Logged Data .........................................................................................8-10
8.6 Time Stamp Accuracy...........................................................................................8-10
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Power Measurement 3720 ACM Installation and Operation Manual
Table of Contents
9 COMMUNICATIONS
9.1 General ....................................................................................................................9-1
9.2 RS-232CCommunication ........................................................................................9-1
9.3 RS-485Communication ...........................................................................................9-2
9.4 Setting the Unit ID & Baud Rate..............................................................................9-2
9.5 3720ACMTRANModelOperation ..........................................................................9-3
9.6 PowerMeasurement'sSCADASystem...................................................................9-3
9.7 Third-PartySystem Compatibility ............................................................................9-3
9.8 ModbusProtocol .....................................................................................................9-4
9.8.1 HardwareRequirementsandWiring.........................................................9-4
9.8.2 SettingCommunicationsParameters ......................................................9-4
9.8.3 CommunicationsProtocol........................................................................9-4
9.9 Allen-BradleyDF-1Protocol ....................................................................................9-6
9.9.1 HardwareRequirementsandWiring.........................................................9-6
9.9.2 CommunicationsProtocol........................................................................9-6
9.10 AlarmDialerProtocol...............................................................................................9-8
9.10.1 HardwareRequirementsandWiring.........................................................9-8
9.10.2 Configuration ...........................................................................................9-8
Appendices
A MECHANICAL& MOUNTINGDIMENSIONS
Basic Model ........................................................................................................... A-1
TRANModel........................................................................................................... A-2
TerminalBlock Dimensions.................................................................................... A-3
B SETPOINTPARAMETERFORM
C FIRMWAREVERSIONS
D TECHNICALSPECIFICATIONS
E MODEL/ORDERINGINFORMATION
F WARRANTYANDREGISTRATION
Warranty ................................................................................................................F-1
ProductReturnProcedure .......................................................................................F-1
Registration .............................................................................................................F-1
G TROUBLESHOOTING
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Power Measurement 3720 ACM Installation and Operation Manual
List of Figures
1. Introduction
1.1.1 3710ACMvs.3720ACMFeatureComparison.............................................................. 1-2
2. Installation
2.1.1 EnvironmentalGuidelinesforInstallation ....................................................................... 2-1
2.5.7a 4 Wire Wye: 3 Element Direct Connection (for 120/208 to 357/600 Volt Systems) ........ 2-5
2.5.7b 4 Wire Wye: 3 Element Connection Using 3 PTs ........................................................... 2-6
2.5.7c 4 Wire Wye: 2½ Element Connection Using 2 PTs........................................................ 2-7
2.5.7d 3 WireGroundedWye:3ElementDirect Connection(120/208-357/600 VoltSystems) . 2-8
2.5.8a 3 Wire Delta System: 2½ Element Connection Using 2 PTs and 3 CTs ........................ 2-9
2.5.8b 3 Wire Delta: 2 Element Connection Using 2 PTs and 2 CTs .......................................2-10
2.5.9 3 Wire Single Phase: 2 Element Direct Connection ......................................................2-11
2.6.2a CommunicationCardJumperConfiguration(ISOCOM2Type) ......................................2-12
2.6.2b ISOCOM2CardTerminalBlock ....................................................................................2-13
2.6.3a 3720MPCCConnectorConfiguration............................................................................2-14
2.6.3b 3720MPEConnectorConfiguration ..............................................................................2.15
2.6.4a RS-232CCommunicationsConnections........................................................................2-17
2.6.4b RS-232CCommunicationCableWiring .........................................................................2-18
2.6.5a RS-485IntermediateTerminalBlockConnections ........................................................2-19
2.6.5b RS-485Straight-LineandLoopTopologies ...................................................................2-20
2.6.5c RS-485Topologiesto Avoid .........................................................................................2-22
2.6.6 MPCCSampleApplication ............................................................................................2-23
2.7.2 FormCControlRelayConnections ...............................................................................2-25
2.7.3 Solid State ControlRelay Option Connections ..............................................................2-26
2.8.1 Status Input Connections for Dry Contact Sensing .......................................................2-27
2.9.1 AuxiliaryVoltageInputConnections .............................................................................2-28
2.10.1 AuxiliaryCurrentOutputConnections ...........................................................................2-28
3. GeneralOperation
3.3.1 Front Panel Display Examples....................................................................................... 3-2
3.3.2 FrontPanelFeatures ..................................................................................................... 3-3
3.4.5 FieldProgrammingExample .......................................................................................... 3-7
3.4.6a ProgrammableOperatingParameters I: Front Panel Access......................................... 3-8
3.4.6b ProgrammableOperatingParameters I: Front Panel Access (cont.).............................. 3-9
3.4.6c ProgrammableOperatingParameters I: Front Panel Access (cont.).............................3-10
3.4.6d ProgrammableOperatingParameters I: Front Panel Access (cont.).............................3-11
3.4.6e ProgrammableOperatingParametersII: CommunicationsAccessOnly ......................3-12
3.4.6f ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-13
3.4.6g ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-14
3.4.6h ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-15
3.4.6i ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-16
3.4.6j ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-17
3.4.6k ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-18
3.4.6l ProgrammableOperatingParametersII:CommunicationsAccessOnly(cont.) ...........3-19
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Power Measurement 3720 ACM Installation and Operation Manual
List of Figures
4. MeasuredParameters&StatusInformation
4.3.1 List of Real-Time Base Measurements & Display Labels............................................... 4-3
4.3.2a Listof MeasurementModesfor Real-TimeParameters ................................................. 4-4
4.3.2b ThermalDemandCalculation ......................................................................................... 4-5
4.4.2 List of Measurement Modes for Energy Parameters ...................................................... 4-7
4.5.1 PowerReadingPolarities ............................................................................................... 4-8
4.6.1 List of Relay, Status Input & Setpoint Display Labels.................................................... 4-9
4.6.2 ExtendedDiagnosticParameters..................................................................................4-10
5. Time-Of-UseSystem
5.2.2 WinTOUSetup:Calendar&ProfileSetupExample ....................................................... 5-1
5.2.4 WinTOU Setup: Register Setup & Real-Time Display Example ..................................... 5-2
6. SetpointSystem
6.1.1 SetpointCapabilities ...................................................................................................... 6-2
6.3.1 SetpointTriggerParameters .......................................................................................... 6-4
6.3.2a OverSetpointOperation................................................................................................. 6-5
6.3.2b UnderSetpointOperation ............................................................................................... 6-6
6.3.4 Time-OvercurrentCurve ................................................................................................. 6-7
6.6.1 SetpointParameterFormExample ...............................................................................6-11
7. WaveformCapture&Recording
7.2.2a M-SCADACapturedWaveformScreen .......................................................................... 7-2
7.2.2b M-SCADAHarmonicSpectrumScreen .......................................................................... 7-2
7.2.2c M-SCADAHarmonicsTableScreen .............................................................................. 7-2
7.3.1 M-SCADAWaveformRecorderScreen .......................................................................... 7-3
7.3.4 WaveformRecorderHigh-SpeedTriggerPointAdjustment ............................................ 7-5
8. On-BoardDataLogging
8.2.1 M-SCADAEventLogScreen ......................................................................................... 8-2
8.3.1 M-SCADA Preset Min/Max Log Screen ......................................................................... 8-3
8.3.2 M-SCADAProgrammableMin/MaxLogScreen ............................................................. 8-4
8.4.1 M-SCADAStandardSnapshotLogScreen .................................................................... 8-5
8.4.2 SnapshotLog Capacity Examples ................................................................................. 8-6
8.4.3a M-SCADAHistoricalTrendingScreen............................................................................ 8-7
8.4.3b One-Shotvs. GatedSnapshot Logging .......................................................................... 8-7
8.4.4 SnapshotLogging:ModesofOperation ......................................................................... 8-9
9. Communications
9.2.1 RemoteCommunicationMethods .................................................................................. 9-2
9.8.1 ModbusSingleandMulti-DropConnections................................................................... 9-5
9.9.1 AllenBradleySingleandMulti-DropConnections .......................................................... 9-7
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Power Measurement 3720 ACM Installation and Operation Manual
Introduction 1-1
1 INTRODUCTION
High Performance Power Instrumentation
The 3720 ACM is a microprocessor-based, digital 3-phase
“Smart Power Monitor/Meter” designed for use in
industrial, commercial, and utility power distribution
switchboards and substations. The 3720 ACM answers the
ever-increasing concern for ‘clean’, reliable power by
integrating the many critical aspects of power monitoring,
analysis, and control into one simple and economical
instrument. It is a state of the art alternative to traditional
analog electromechanical metering devices, replacing
numerous individual transducers and meters, and offering
many features previously unavailable in power instru-
mentation.
The 3720 ACM offers the high accuracy, reliability, and
ruggedness of its companion product, the successful
3710 ACM, while adding many new measurements and
advanced features (see Figure 1.1.1). The 3720 ACM also
matches the 3710 ACM in its mounting dimensions,
installation requirements, and in its straightforward and
flexible user interface.
The unit is based around a 13.5 MHz, 16 bit
microcontroller chip. This provides very high computa-
tional throughput, allowing the unit’s sophisticated
software to process information in real time. The unit is
self-contained and its readings and set up parameters are
maintained in nonvolatile memory. An internal 16-bit
CPU gives the 3720 ACM the processing capability to be
used as a stand-alone power monitoring and control
station or as a smart RTU in a large energy monitoring
network.
Easy Installation and Exceptional Ruggedness
The 3720 ACM is panel-mountable and provides rear-
mounted, utility approved terminal strips rated at 600V.
The 3720 ACM is exceptionally rugged, with a high
tolerance to electrical disturbances and temperature
extremes. Many special design features guarantee perfor-
mance in electrically harsh environments. The voltage,
current, status (digital), relay, supply power, and commu-
nications inputs are designed to withstand hipot, C37.90A
SWC, and fast transient tests. The 3720 ACM transformer-
coupled current inputs are fully isolated with respect to
the chassis of the unit, and provide 300 Amp surge
protection.
Inputs and Outputs
The 3720 ACM supports a variety of power distribution
configurations, including 4-wire Wye, 3-wire Delta, and
Single Phase systems. 3 phase voltage and 3 phase current
inputs are provided, as well as an additional current
input. In installations with non-linear loads, where odd
harmonics can fail to cancel, significant currents in the
neutral conductor can be produced. The 3720 ACM fourth
current input can be used optionally for monitoring
current in the neutral conductor, or for ground current
monitoring. Used in conjunction with its high-speed
setpoint system, the 3720 ACM can provide reliable
ground fault protection.
No intermediate transducers are required on phase
voltage and current inputs. When equipped with the
appropriate voltage input option, no PTs are required for
Wye systems up to 347 VAC line-to-neutral / 600 VAC
line-to-line. For higher voltage Wye systems, and all Delta
systems, PTs can be used. The transformer-coupled
current inputs accept CTs with 5 Amp full scale outputs.
A 1 Amp input version is also available. Overrange
measurement options include 125% to 1000%.
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