1SVR550805R9300

The ABB 1SVR550805R9300 (CM-MSE) is a high-quality thermistor motor protection relay designed to monitor motor winding temperature and help protect electric motors against excessive heating. Manufactured by ABB, this monitoring relay operates with a rated control supply voltage of 24V AC and features one normally open (1 NO) output contact. It is designed for use with compatible PTC temperature sensors embedded in motor windings, providing dependable temperature monitoring for industrial motor protection applications. Its compact construction makes it suitable for installation in electrical control panels, motor control centres, and industrial automation systems.

The ABB CM-MSE thermistor motor protection relay continuously monitors the resistance of connected PTC temperature sensors. When the motor winding temperature reaches the sensor's specified response temperature, the PTC resistance increases and the relay detects the abnormal condition. The output changes state, allowing a properly designed motor control circuit to disconnect or inhibit the motor and help prevent overheating damage.