GE SR489-P5-LO-A20 Generator Management Relay

GE SR489-P5-LO-A20 is a Generator Management Relay manufactured by General Electric under the GE Multilin product line. It belongs to the Multilin 489 series and is widely used in industrial power systems for generator protection, monitoring, and control.

1. Product Overview

The GE SR489-P5-LO-A20 is a microprocessor-based protection relay designed to provide comprehensive protection and management for synchronous or induction generators.

It continuously monitors key electrical parameters such as current, voltage, frequency, and power, and can quickly initiate alarms or trip signals in case of abnormal conditions, ensuring the safe and reliable operation of generators and associated power systems.

Typical application industries include:

• Power generation plants

• Petrochemical facilities

• Metallurgical industries

• Data center backup power systems

• Industrial automation power systems

2. Model Designation

The model number SR489-P5-LO-A20 indicates specific configuration options:

• SR489 – Multilin 489 series generator/motor protection relay

• P5 – 5 A current transformer (CT) input

• LO – Low control power supply (approximately 20–60 VDC / 20–48 VAC)

• A20 – Provides 4–20 mA analog output

These options allow the relay to adapt to different industrial power system requirements.

3. Key Functions

Electrical Protection

• Overcurrent protection

• Under/over voltage protection

• Reverse power protection

• Loss of field protection

• Current unbalance protection

• Overload and short-circuit protection

Monitoring and Control

• Real-time monitoring of voltage, current, frequency, and power factor

• Generator operating status supervision

• Event recording and fault diagnostics

• Circuit breaker control and automatic restart logic

4. Main Technical Specifications (Typical)

• Power supply: 20–60 VDC or 20–48 VAC

• CT input: 5 A

• Analog output: 4–20 mA

• Communication interfaces: RS232 / RS485

• Communication protocols: Modbus RTU, DNP3

• Operating temperature: -40°C to +70°C

• Dimensions: approximately 216 × 224 × 252 mm

• Weight: approximately 2–3 kg

Summary

The GE SR489-P5-LO-A20 is a high-reliability generator protection and management relay from General Electric’s GE Multilin 489 series. It integrates advanced protection, monitoring, and communication capabilities, making it suitable for a wide range of industrial power and generator control applications.