The RW overload relays protect loads against overheating caused by overloads or phase loss.
When there is an overload or a phase loss in the circuit, the motor current increases. These current rises activate the tripping mechanism that in turn actuates the auxiliary contacts 95-96 (NC) and 97-98 (NO).
The auxiliary contacts disconnect the load by means of a contactor. The time for disconnection is related to the overload current and the current set on the relay, which is properly represented on the relay tripping curve. After the trip, it is necessary to wait for the system to re-establish in order to do the reset, which can be done automatically or manually.