The Siemens electronic overload relays are used to protect the loads against high-resistance short circuits due to damage to the insulation, humidity, condensed water, etc. They have been designed for inverse-time delayed protection of loads with normal and heavy starting against excessive temperature rises due to overload, phase asymmetry or phase failure. An overload, phase asymmetry or phase failure result in an increase of the motor current beyond the set rated motor current. 3 number of poles