GE PQMII Instruction Manual

Contents

PQMII POWER QUALITY METER – INSTRUCTION MANUAL 1–1PQMII Power Quality MeterChapter 1: OverviewDigital EnergyMultilinOverview1.1 Introduction to the PQMII1.1.1 DescriptionThe GE Multilin PQMII Power Quality Meter is an ideal choice for continuous monitoring of asingle or three-phase system. It provides metering for current, voltage, real power, reactivepower, apparent power, energy use, cost of power, power factor, and frequency.Programmable setpoints and four assignable output relays allow control functions to beadded for specific applications. This includes basic alarm on over/under current or voltage,unbalance, demand-based load shedding, and capacitor power factor correction control.More complex control is possible using the four switch inputs; these can also be used forstatus information such as breaker open/closed and flow information.As a data gathering device for plant automation systems that integrate process,instrument, and electrical requirements, all monitored values are available via one of twoRS485 communication ports running the Modbus protocol. If analog values are requiredfor direct interface to a PLC, any of the monitored values can output as a 4 to 20 mA (or 0to 1 mA) signal to replace up to four (4) separate transducers. A third RS232communication port connects to a PC from the front panel for simultaneous access ofinformation by other plant personnel.With increasing use of electronic loads such as computers, ballasts, and variablefrequency drives, the quality of the power system is important. With the harmonic analysisoption, any phase current or voltage can be displayed and the harmonic contentcalculated. Knowledge of the harmonic distribution allows action to be taken to preventoverheated transformers, motors, capacitors, neutral wires, and nuisance breaker trips.Redistribution of system loading can also be determined. The PQMII can also providewaveform and data printouts to assist in problem diagnosis.