1SVR740700R0100

The ABB 1SVR740700R0100 (CM-MSS.12P) is a high-quality thermistor motor protection relay designed to monitor motor winding temperatures and protect industrial electric motors against excessive heating. Manufactured by ABB, this relay belongs to the CM-MSS series and operates with a rated control supply voltage of 24V AC/DC. It features one changeover (SPDT) output contact rated at 250V and 4A, providing dependable switching functionality for industrial motor protection circuits. The relay includes one sensor circuit for monitoring compatible PTC thermistors installed in motor windings, making it suitable for industrial machinery, electrical control panels, and automation systems.

The ABB CM-MSS.12P 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 sensor resistance rises, allowing the relay to detect an overheating condition. Its output contact changes state so that a correctly designed motor control circuit can stop or inhibit motor operation. The relay operates according to the closed-circuit principle and provides automatic reset after the fault condition has cleared.