Designed to monitor thermocouples and provide a relay signal if the temperature being monitored exceeds the pre- set limit. J and K type thermocouples inputs are available covering a wide range of temperatures. As is common with all the M200 relays, on over units the relay energizes when the input signal exceeds the trip point and on under units the relay de-energizes when the input signal goes below the trip point. A red LED indicates the state of the relay, whilst a green LED indicates the condition of the power supply.