Description

GE Multilin 239-AN Motor Protection Relay

Configured for three-phase AC induction motor protection and analog telemetry execution in GE Multilin 239 Motor Protection Relay platforms, the GE Multilin 239-AN (239-AN Motor Protection Relay) provides direct physical/electrical execution.

Hardware Specifications

Parameter	Specification
Model	GE Multilin 239-AN
Brand	GE Multilin
Weight	5 lbs
Dimensions	1/4 DIN standard panel mount footprint
Operating Temp	-20 deg C to +60 deg C
Power Consumption	Max 10 VA AC / 10 W DC
Control Power Supply	90-300 VDC / 70-265 VAC or 20-60 VDC / 20-48 VAC depending on model
Phase Current Inputs	1 A or 5 A CT secondary, field configurable
Analog Output	4-20 mA or 0-1 mA DC programmable output
Communication Port	RS485 serial interface
Communication Protocol	Modbus RTU / GE Multilin protocol
Relay Outputs	Assignable Form-C (SPDT) relays
Relay Contact Rating	8 A continuous at 250 VAC / 30 VDC
Frequency Range	20 to 70 Hz
Display Interface	LCD display with status and trip LEDs
Mounting Type	Panel mount

GE Multilin Industrial Control Communication Features

The GE Multilin 239-AN integrates motor protection measurement with PLC/DCS interface functions through an isolated RS485 communication channel and programmable analog output. The 4-20 mA or 0-1 mA signal output can transmit thermal capacity used, motor load current, and related operating values for external monitoring systems.

The relay supports deterministic serial communication through Modbus RTU protocol and GE Multilin communication protocol. The module includes a 36 VDC isolated active source communication interface with configurable baud rates from 1200 to 12k bps.

The firmware-controlled protection platform performs thermal modeling, current measurement, and trip logic processing. Functions include thermal overload protection with memory, short circuit detection, ground fault monitoring, phase loss detection, phase unbalance protection, locked rotor protection, undercurrent detection, and RTD or thermistor temperature input monitoring when equipped.

Frequently Asked Questions

Q: Does the GE Multilin 239-AN support hot-swap replacement during operation?
A: The 239-AN is designed as a panel-mounted motor protection relay. Hot-swap operation is not specified. Replacement should be performed with the motor circuit and relay control power isolated according to site procedures.

Q: What communication interface is available for PLC or DCS integration?
A: The relay provides an isolated RS485 serial port supporting Modbus RTU and GE Multilin communication protocol.

Q: How are motor current signals processed by the relay?
A: The relay accepts 1 A or 5 A CT secondary inputs and performs RMS measurement, protection calculations, and thermal model processing.

Field Installation Guidelines

Install the GE Multilin 239-AN in a standard 1/4 DIN panel cut-out with adequate clearance for wiring access and maintenance. Verify that control power voltage matches the selected relay power supply range before energization.

Use twisted shielded wiring for RS485 communication connections where required by the installation environment. Connect cable shields according to site grounding practices to reduce electrical noise coupling into low-level communication and measurement circuits.

Route CT input wiring separately from high-voltage power conductors to minimize induced interference. Confirm CT polarity, secondary ratings, and grounding practices before commissioning the motor protection functions.

Configure protection parameters, analog output scaling, communication address, and trip logic settings before placing the motor circuit into service. Verify relay input states and output contact operation through functional testing.

Specifications

• Brand: General Electric

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems