Name: SR489-P5-LO-A20-E GE Multilin Generator Management Relay, 5A CT, 4-20mA AO, Low Control Power - MASSIVE
Brand: General Electric

Description

SR489-P5-LO-A20-E GE Multilin Generator Management Relay, 5A CT, 4-20mA AO, Low Control Power

Product Application

SR489 is a dedicated multifunction generator protection relay for medium/small synchronous and induction generators. It delivers primary and backup electrical fault protection plus thermal monitoring for stator and bearings. This model provides 4 isolated 4–20mA analog outputs for sending real-time generator parameters to DCS/PLC (e.g. IC695ETM001, VersaMax). It records events and oscillography for post-fault analysis, supports breaker control, synchronism check and generator motoring protection. Typical sites: CHP combined cycle, diesel/gas gen-set, captive power plant, backup generator protection.

SR489-P5-LO-A20-E

Product Specifications

Part Number: SR489-P5-LO-A20-E
Manufacturer: GE Multilin / GE Vernova
Product Type: Generator Management Multifunction Protection Relay
CT Input: 5A secondary (P5)
VT Input: 4 voltage transformer inputs
Control Power (LO): 20–60 VDC or 20–48 VAC (48–62Hz)
Analog Output (A20): 4 × isolated 4–20mA
RTD Input: 12 channels for stator / bearing temperature monitoring
Digital Inputs: 9 programmable dry-contact digital inputs
Relay Outputs: 6 × Form-C trip/alarm relay contacts
Communication: Front RS232, rear dual RS485
Protocols: Modbus RTU, DNP3.0 (option)
Sampling Rate: 12 samples per cycle
Event Recorder: 40 events with time stamp
Oscillography: 64 cycles fault waveform capture
Frequency Support: 25 / 50 / 60Hz
Display: Front panel 40-character LCD + keypad & LED status indicators
Construction: Drawout case with automatic CT shorting on withdrawal
Mounting: Panel mount
Operating Temperature: -40 ℃ ~ +60 ℃
Humidity: 5% ~95% RH non-condensing
Pollution Degree: 2
Product Status: Mature legacy protection relay, spares & service available
Approx. Weight: 7.7 kg

Core Technical Parameters

Protection elements: % stator differential, 100% stator ground fault, negative sequence overcurrent, loss of excitation, reverse power (anti-motoring), over/under voltage, over/under frequency, phase overcurrent, thermal overload
RTD thermal model: uses stator/bearing RTDs to bias overload curve, sensor open/short detection
Drawout design: CT shorting mechanism prevents dangerous open CT condition when relay pulled out
4-20mA AO channels assignable to real values: MW, Mvar, voltage, current, temperature etc.
IRIG-B time synchronization option for high-precision event timestamp
489PC software for setpoint configuration, metering view, oscillography download and relay simulation
Flash memory for firmware upgrade without hardware replacement

Recommended Matching Spare Parts & Accessories (8 Items)

5A CTs & generator neutral core-balance CT
Voltage transformers VT
RTD sensors (stator & bearing PT100)
Shielded twisted pair signal cables
489PC configuration software
Replacement drawout case contacts
IRIG-B time sync module (if required)
Surge protection modules for CT/VT/RTD wiring

SR489-P5-LO-A20-E

Product Features

✅ Full Suite Generator Protection Differential, stator ground, loss of excitation, reverse power, thermal overload and frequency/voltage protection for generator main and backup protection.

✅ 12-Channel RTD Temperature Monitoring Monitor stator winding and bearing temperatures, thermal model protects against overheating, RTD fault detection.

✅ 4 Isolated 4–20mA Analog Outputs Transmit generator operating parameters to DCS/PLC analog inputs.

✅ Drawout Construction with Auto CT Short When relay withdrawn, CT secondary automatically shorted for safety, simplify maintenance.

✅ Multiple Serial Communication Ports Front RS232 local commissioning; dual rear RS485 for SCADA/Modbus RTU to PLC/DCS.

✅ Event Log & Oscillography 40 event records and 64-cycle oscillography for fault post-mortem analysis.

✅ Wide Range Low Control Power Supply 20–60VDC / 20–48VAC, tolerant of auxiliary power fluctuation in power plants.

Installation Guidelines

Install relay into control panel cutout, secure drawout housing.
Wire CT, VT, RTD, digital inputs and trip relay outputs per single-line diagram.
Connect control power (20–60VDC / 20–48VAC).
Wire RS485 Modbus bus to DCS/PLC or RS232 to local laptop.
Use 489PC or front keypad to configure CT/VT ratios, generator rated parameters, protection setpoints and 4–20mA assignments.
Perform secondary injection test to verify all protection elements and I/O.
Test breaker trip/alarm outputs, event recording and oscillography function.
Complete generator static test and synchronizing test before generator rolling.

Maintenance Instructions

Daily Maintenance Check front panel LED/LCD for relay health, alarms and metering values; monitor generator protection alarms in SCADA.

Periodic Maintenance (Every 6–12 months) Inspect CT/VT wiring, RTD cable integrity; check drawout contacts; backup relay setting file. Perform secondary injection test per protection maintenance schedule.

Fault Maintenance

Relay fault / self-test alarm: inspect control power supply, check drawout contacts.
Protection misoperation: review oscillography and event log, verify CT/VT wiring and setpoints.
4-20mA AO abnormal: check analog output assignment, loop wiring and load resistance.

Do not modify generator protection setpoints without power system protection engineer approval.

Long-Term Operation Tips Maintain panel temperature -40~+60℃. Store spare SR489-P5-LO-A20-E in dry anti-static environment, always backup setting file.