The unit is for use with equipment that has in-built thermistors to DIN 44081 and will monitor up to 6 thermistors in a chain. When the resistance of the thermistors rise above the release level, or a short circuit is detected, the relay will de-energise. When the reset level is reached the relay will energise once again. If Y1 and M are linked together the unit remains latched until the reset button is either pressed or the link or the supply is removed.
Thermistor over-temperature
Thermistor short circuit
Thermistor open circuit