This relay operates with a rated control supply voltage of 24 V AC / DC and has a 2 c/o (SPDT) output with contacts rated at 250 V / 4 A. The CM-TCS.21S is able to measure temperature with 1 sensor circuit using PT100 sensor. The CM-TCS.21S monitors overtemperature, undertemperature and window monitoring with 2 thresholds. The corresponding threshold values are adjustable. The temperature measuring range is -50..+50°C. A sealable transparent cover for protection against unauthorized changes is available as accessory. The device offers screw connection technology with double-chamber cage connection terminals.