GE Industrial Solutions POWER LEADER PMCS Network Architecture Guide - Manual (Page 59)

Power Management Control System
Appendix A – IED Descriptions
49
Overview
A power management system consists of a host IED
connected via a communication network to metering
and protective IEDs. PMCS supports up to 256 RS-485
Modbus RTU communication networks, to which are
attached various power management IEDs. Each RS-485
network is capable of supporting up to 247 IEDs on up
to 4000 feet of interconnecting shielded, twisted-pair
cable per network. The network protocol is peer-to-peer,
contention-sensing, multiple-access, collision-detection
(CSMACD).
This appendix lists the features and functions of various
IEDs that are compatible with Power Management
Control System. The title bar above each IED gives its
name and its general function. This is followed by a
brief description of the IED and its features and
functions.
239 Motor Protection Relay
The 239 relay is designed to fully protect three-phase ac
motors against conditions that can cause damage. In
addition to motor protection, the relay has features that
can protect associated mechanical equipment, give an
alarm before damage results from a process
malfunction, diagnose problems after a fault, and allow
verification of correct relay operation during routine
maintenance.
Using the Modbus serial communications interface,
motor starters throughout a plant can be connected to a
central control and monitoring system for continuous
monitoring and fast fault diagnosis of a complete
process.
One relay is required per motor starter. Setpoints are
entered via the front panel or with a computer. Status,
actual values, and trouble-shooting information are
available in clear English from the front-panel display.
A simulation mode and pickup indicator allow testing
and verification of correct operation without requiring
a relay test set.
With the use of the RTD option, up to three RTDs can
be monitored. These can all be in the stator or one in
the stator and two in the bearings. An optional analog
output is also available for direct PLC interface or
metering of the motor thermal capacity.
Installing a 239 relay in a motor starter for protection
and monitoring of small- to medium-sized motors will
minimize downtime due to process problems.
Application
• Small- to medium-sized motors
• Pumps, conveyors, compressors, fans, sawmills,
mines
• Variable-frequency drives
Protection
• Overload (15 selectable curves)
• Phase short circuit
• Locked rotor/mechanical jam
• Thermal memory lockout
• Single phase/unbalance
• Ground fault
• Overtemperature: thermistor
• Additional three RTDs optional
• Undercurrent
• Trip/alarm/auxiliary/service outputs
• Five switch inputs
Monitoring and Metering
• Status/current/temperature display
• Process control
• Optional analog output
• Simulation mode for field testing
User Interface
• RS-485 Modbus communications
• 40-character illuminated display
• Six LED indicators
• Keypad
Features
• ac/dc control power
• Compact size, fits most motor starters
• NEMA12/IP53 enclosure
269+ Motor Management Relay
The 269 Plus Motor Relay provides complete, accurate
protection for industrial motors and their associated
mechanical systems, offering a wide range of protection,
monitoring, and diagnostic features including the
following (functions with an asterisk require the
optional Meter Transducer Module):
Metering
• Currents (Ia, Ib, Ic)
• Ground Current
• Voltages* (Va-b, Vb-c, Vc-a)
• kW*, kVAR*
• Power Factor*