GE 269PLUS-100P-120 Motor Management Relay

GE  269PLUS-100P-120  motor management relay

The GE 269PLUS-100P-120 is a motor management relay manufactured by GE Multilin. The detailed introduction is as follows:

Basic Characteristics

• Resistance and Temperature Detection: Equipped with a 100-ohm platinum RTD (Resistance Temperature Detector) for accurate temperature measurement, monitoring the motor's thermal status, and protecting it from thermal overload.

• Operating Temperature Range: The ambient temperature for storage and operation should be between -25°C and 60°C.

• Dimensions: The shipping box size is 11.40 inches x 7.50 inches x 16.00 inches (width x height x depth), and the shipping weight is 7.75 pounds.

Protection Functions

• Thermal Protection: Features an enhanced thermal model including current unbalance and RTD bias. It monitors temperature via programmable RTD inputs to protect the stator, bearings, and ambient temperature, preventing overheating of stator windings and bearings.

• Overload Protection: Provides 8 standard overload curves and supports user-defined overload FlexCurve™ curves, which can be set according to motor characteristics to avoid false tripping.

• Other Protections: Offers protections against unbalance/single-phase, phase reversal (with meter option), locked rotor, quick trip/mechanical seizing, etc. It can detect abnormal conditions such as motor current drop and issue alarms.

Control Functions

• Supports multiple motor start controls, emergency restart function, and pre-trip alarm warnings. It can also combine all protection functions through the main relay to achieve comprehensive control of the motor's starting and operating processes.

Monitoring and Metering Functions

• Capable of current and thermal capacity metering, with a data recorder that logs motor operation and learning data, last trip data, etc. Voltage and power metering functions are optional to help users understand the motor's operating status and energy consumption.

Input/Output Configuration

• Includes 12 programmable RTDs, 5 factory-programmed digital inputs, 4 output relays, and 1 programmable analog output, meeting the connection and control needs of various external devices.

Communication Functions

• Equipped with a standard RS485 serial port supporting Modbus RTU communication protocol, enabling cost-effective information access for integration with other devices or systems to achieve comprehensive factory control.

Programming and Display

• Features a 12-key keypad and a simple LED display for quick and easy programming. The LED display provides real-time information about the motor and equipment, facilitating diagnosis and problem-solving.

Specific Working Principles

• Temperature Monitoring Principle: The module has an internal 100-ohm platinum RTD, whose resistance changes with temperature. The module calculates the temperature by measuring the resistance. For example, RTD1-3 and RTD4-6 are generally used to monitor stator winding temperature, while RTD7-10 can monitor motor bearing and ambient temperature to determine if the motor is overheating.

• Current Monitoring and Protection Principle: The module continuously monitors the three-phase current of the motor. When current unbalance occurs, it calculates the negative sequence current. If the value exceeds the set threshold, it determines a motor fault and triggers the protection mechanism. For overload, the module calculates the motor's thermal accumulation by continuously monitoring current magnitude and time based on 8 preset standard overload curves or user-defined FlexCurve curves. When the thermal accumulation reaches the set overload threshold, overload protection is triggered. In case of locked rotor or mechanical seizing, the current is much larger than the normal operating current. The module detects the abnormal current increase and executes a trip operation after exceeding the specified time to protect the motor.

• Fault Judgment and Protection Action Principle: The module analyzes signals from various sensors based on built-in microcomputer programs and algorithms. When detected parameters exceed preset protection thresholds (such as excessive temperature or abnormal current), the module controls internal relays. The main trip relay cuts off the motor power, while the alarm relay sends an alarm signal to notify operators of motor faults.

• Data Communication and Control Principle: The module has an RS485 serial port supporting Modbus RTU protocol. Through this port, it can transmit real-time motor operation parameters and fault information to programmable controllers or computers for remote monitoring. It can also receive control commands from external devices (such as starting/stopping the motor and modifying protection parameters) to achieve comprehensive factory control.

• Motor Matching and Self-Learning Principle: The module has a motor matching function, which acquires motor characteristic parameters (such as cooling time and acceleration time) through "self-learning" and stores them in memory. It also accumulates I²t measurements. By comparing the calculated motor I²t value (thermal model) with the stator temperature measured by RTD, the higher value is used for motor protection, thus more accurately adapting to the protection needs of different motors and improving the accuracy and reliability of protection.