The ABB CM‑MSS.S (SVRR) is a DIN‑rail thermistor-based motor protection relay designed to safeguard motors and generators from overheating. It supports PTC thermal sensors and provides advanced features like short-circuit and wire-break detection, automatic reset, and ATEX certification—ideal for industrial environments.

Key Features:

• Model: CM‑MSS.S / SVRR

• Supply Voltage: – V AC/DC

• Sensor Input: Single PTC thermistor circuit (DIN EN /)

• Outputs: N/O + N/C (SPDT),  A @  VAC /  A @  VDC

• Fault Detection: Overtemperature, short-circuit, open-wire; auto-reset on recovery

• Indicators: Green power, yellow relay status, red fault LEDs

• ATEX Certified: Suitable for hazardous area use

• Mounting & Wiring: . mm DIN-rail; screw-terminals with cage technology; IP housing, IP terminals

• Operating Temp: − °C to + °C; withstands ‑kV impulse, IEC ‑ certified

• Dimensions: . × . × . mm, weight ~ g

ABB – 1SVR730722R1400 – CM-MSS.21S Thermistor Motor Protection Relay, 24–240 VAC

ABB – 1SVR730722R1400 – CM-MSS.21S Thermistor Motor Protection Relay, 24–240 VAC