Thermal Overload Relays

These types of relays consist of bimetallic elements, which are individually calibrated and tested for optimum protection of motors against overloads. The tripping curve shows the inverse time characteristic of all bimetallic relays starting from cold condition. Once the realy is tripped due to overload it cannot be reset immediately as the relay has a specific reset time. Resetting is done maually. Wide range of relays are available depending on various ac loads.