Model No.
GE Multilin 239-RTD-AN is a high-performance digital motor protection relay belonging to the GE Multilin 239 series. It is specifically designed for small to medium-sized three-phase AC motors and related mechanical equipment, providing comprehensive automated protection by monitoring current, voltage, and temperature.
Discontinued Status: The 239 series is currently classified as a Legacy product. Although GE and its successor (GE Vernova / Grid Solutions) have introduced the more modern 339 series,
The suffixes in the 239-RTD-AN designation have specific meanings:
239: Denotes the base motor protection series.
RTD: Indicates this model is equipped with an RTD (Resistance Temperature Detector) input card, enabling direct monitoring of motor winding or bearing temperatures.
AN: Indicates the model features an Analog Output function, converting monitored parameters (such as current or temperature) into 4-20mA or 0-1mA signals for transmission to PLCs or DCS systems.
This compact device is typically mounted on motor starters or control cabinet door panels.
1. Key Features
Thermal Overload Protection: Core function. Utilizes advanced thermal modeling algorithms to calculate the motor’s Thermal Capacity Utilization (TCU), preventing winding burnout due to overheating.
Temperature Monitoring: Supports 3 programmable RTD inputs (compatible with Pt100 platinum resistors, Ni120 nickel resistors, etc.) to monitor motor stator or bearing temperatures.
Electrical Fault Protection:
Short Circuit Protection: Instantaneous tripping.
Ground Fault Protection: Monitors leakage caused by insulation failure.
Current Unbalance Protection: Prevents rotor overheating due to single-phase operation or phase imbalance.
Mechanical Protection:
Mechanical Jam: Detects sudden load lock-up.
Reverse Rotation Protection: Monitors current phase sequence.
Status Monitoring & Communication: Features a backlit LCD display with Modbus RTU communication (RS485 interface) for remote reading of real-time current, temperature, and the last 5 fault records.
2. Application Scenarios
This relay is widely used in industrial sectors demanding high reliability:
Pumps and Fans: Water treatment, chemical processing, HVAC systems.
Conveying Equipment: Mining, logistics automation, conveyor belt monitoring.
Compressors: Oil and gas, manufacturing plants.
Woodworking and Pulp & Paper: Heavy-duty machinery like sawing machines and grinders.
There are no reviews yet.