GE Pqm 2 Manual

							CHAPTER 1: OVERVIEW
PQMII POWER QUALITY METER  – INSTRUCTION MANUAL1–3
FIGURE 1–1: Single Line Diagram
Four (4)
output
relays
Four (4)
transducer
outputs
4 3 2 1
COM 2
RS232
PORT COM 1 Four switch
inputs for
control–
4to20mA Alarm
control Instrumentation
Electrical
MaintenanceMain
SCADAThree-phase
3/4-wire bus
CTs
VTs 0 to 600 V direct
> 600V CT/VTs
Control
power
(AC/DC)
PLC
or
RTU
PQMII
PC running
EnerVista PQMII Setup746701A1.CDR 
						

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FIGURE 1–2: Feature Highlights 
						

							CHAPTER 1: OVERVIEW
PQMII POWER QUALITY METER  – INSTRUCTION MANUAL1–5
1.2 Standard Features
1.2.1 Metering
True RMS monitoring of Ia, Ib, Ic, In, Van, Vbn, Vcn, Vab, Vbc, Vca, voltage/current 
unbalance, power factor, line frequency, watts, vars, VA, Wh, varh, VAh, and demand 
readings for A, W, vars, and VA. Maximum and minimum values of measured quantities are 
recorded and are date and time stamped.
A 40-character liquid crystal display is used for programming setpoints and monitoring 
values and status.
1.2.2 Alarms
Alarm conditions can be set up for all measured quantities. These include overcurrent , 
undercurrent , neutral current , current unbalance, voltage unbalance, phase reversal, 
overfrequency, underfrequency, power factor, switch inputs, etc. The alarm messages are 
displayed in a simple and easy to understand English format .
1.2.3 Communications
The PQMII is equipped with one standard RS485 port utilizing the Modbus or DNP 
protocols. This can be used to integrate process, instrumentation, and electrical 
requirements in a plant automation system by connecting several PQMII meters together 
to a DCS or SCADA system. A PC running the EnerVista PQMII Setup Software can change 
system setpoints and monitor values, status, and alarms. Continuous monitoring 
minimizes process downtime by immediately identifying potential problems due to faults 
or changes from growth.
The PQMII also includes a front RS232 port which can be used for the following tasks:
• data monitoring
• problem diagnosis
•viewing event records
•trending
• printing settings and/or actual values
• loading new f irmware into the PQMII
1.2.4 Future Expansion
Flash memory is used to store f irmware within the PQMII. This allows future product 
upgrades to be loaded via the serial port . 
						

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FIGURE 1–3: Downloading Product Enhancements via the Serial Port
1.2.5 Open Architecture
PQMII units can initially be used as standalone meters. Their open architecture allows 
connection to other Modbus compatible devices on the same communication link. These 
can be integrated in a complete plant-wide system for overall process monitoring and 
control. 
						

							CHAPTER 1: OVERVIEW
PQMII POWER QUALITY METER  – INSTRUCTION MANUAL1–7
1.3 Optional Features
1.3.1 Transducer Input/Outputs
Four isolated 4 to 20 mA (or 0 to 1 mA depending on the installed option) analog outputs 
are provided that can replace up to eight transducers. The outputs can be assigned to any 
measured parameters for direct interface to a PLC.
One 4 to 20 mA analog input is provided to accept a transducer output for displaying 
information such as temperature or water level.
An additional rear RS485 communication port is provided for simultaneous monitoring by 
process, instrument , electrical, or maintenance personnel.
FIGURE 1–4: Additional Communication Port
1.3.2 Control Option
An additional three dry-contact form “C” output relays and four dry-contact switch inputs 
are provided. These additional relays can be combined with setpoints and inputs/outputs 
for control applications. Possibilities include:
• undercurrent alarm warnings for pump protection
• overvoltage/undervoltage for generators
• unbalance alarm warnings to protect rotating machines
• dual level power factor for capacitor bank switching
• underfrequency/demand output for load shedding resulting in power cost saving
• kWh, kvarh and kVAh pulse output for PLC interface
• Pulse input for totalizing quantities such as kWh, kvarh, kVAh, etc. 
						

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FIGURE 1–5: Switch Inputs and Outputs Relays
1.3.3 Power Analysis Option
Non-linear loads (such as variable speed drives, computers, and electronic ballasts) can 
cause unwanted harmonics that may lead to nuisance breaker tripping, telephone 
interference, and transformer, capacitor or motor overheating. For fault diagnostics such 
as detecting undersized neutral wiring, assessing the need for harmonic rated 
transformers, or judging the effectiveness of harmonic f ilters, details of the harmonic 
spectrum are useful and available with the power analysis option.
FIGURE 1–6: Harmonic Spectrum 
						

							CHAPTER 1: OVERVIEW
PQMII POWER QUALITY METER  – INSTRUCTION MANUAL1–9
Voltage and current waveforms can be captured and displayed on a PC with the EnerVista 
PQMII Setup Software or EnerVista Viewpoint . Distorted peaks or notches from SCR 
switching provide clues for taking corrective action.
FIGURE 1–7: Captured Waveform
Alarms, triggers, and input/output events can be stored in a 150-event record and time/
date stamped by the internal clock. This is useful for diagnosing problems and system 
activity. The event record is available through serial communication. Minimum and 
maximum values are also continuously updated and time/date stamped. 
						

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FIGURE 1–8: Data Logger
Routine event logs of all measured quantities can be created, saved to a f ile, and/or 
printed.
For additional information on waveform sampling and analysis features, see Power 
Analysis on page 4–13.
The power analysis option also provides a Trace Memory feature. This feature can be used 
to record specif ied parameters based on the user def ined triggers. 
						

							CHAPTER 1: OVERVIEW
PQMII POWER QUALITY METER  – INSTRUCTION MANUAL1–11
FIGURE 1–9: Trace Memory Capture 
						

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1.4 EnerVista PQMII Setup Software
1.4.1 Overview
All data continuously gathered by the PQMII can be transferred to a third party software 
program for display, control, or analysis through the communications interface. The 
EnerVista PQMII Setup Software allows the user to view and manipulate this data and 
assists in programming the PQMII. Some of the tasks that can be executed using the 
EnerVista PQMII Setup Software package include:
• reading metered data
• monitoring system status
• changing PQMII setpoints on-line
• saving setpoints to a f ile and downloading into any PQMII
• capturing and displaying voltage and current waveforms for analysis
• recording demand prof iles for various measured quantities
• troubleshooting communication problems with a built in debugger
• printing graphs, charts, setpoints, and actual values
The EnerVista PQMII Setup Software is fully described in  Software on page 4–1.
FIGURE 1–10: EnerVista PQMII Setup Software Main Window