at an economical price the base unit protects against overloads phase ... imbalance in motors from 1 to 820a thermistor connections and optional ground-fault ... newly-developed sensor systems and trippingunits make the zev electronic overload ... the-range in motor protection enhanced tripping classes provide reliable protection for ... faults quickly while an integrated thermistor connection makes it easy to upgrade to ... for communication of ground faults thermistor trips internal faults or early warning ...