Industry standard 11 Pin Plug-in modules for 12 or 24VDC supplies. Thermistor trips are typically used in Gen-Set applications where PTC thermistors are embedded directly into the the windings of the main Alternator. In 2 or 3-phase machines the thermistors are normally connected in series and the abrupt rate of change in resistance at the specified trip temperature is detected by the THM400. However, these units are used in many other industries where temperature alarm monitoring is required and can be ordered for use with thermistors having Positive (PTC) or Negative (NTC) temperature coefficients. An integral delay timer prevents false tripping and an Internal precision resistor aids calibration and testing. LED’s indicate Power (dc supply), Level (out of limits) and Relay (status). Relay energises at trip point (internal slide switch to reverse) with SPCO volt-free contacts rated at 16A AC1. Customised versions are available to order.