The SPEM relay is based on microprosessor techniques with a built in logic supervising thermal behaviour of motor.
The thermal capacity memory monitors the motor current and continuously compares the data to the known thermal record of the motor, and operates when the thermal limit of the motor is exceeded.

The microprosessor based construction ensures long time stability, high accuracy and disturbance free operation.

The compact size enables installation in cramped places.

The SPEM relay is the ideal answer to problems requiring more versatile or accurate protection for a motor than can be offered by a standard thermal overload relay.

SPEM relays can be used for protecting low voltage squirrel cage (AC) motors 1) .

Use of SPEM motor protection relay:

• helps in extending life time of motor
• helps in optimizing motor size
• helps in planning maintenance work
• protects the drive from mechanical damage

Courtesy of ABB