What is the difference between Relay and Contactor

Answer Posted / sandeep

Contactor is a switching device. Unless & until you give
command it wont operate. Contactor is not a sensing device.
on the other hand Relay is the device which sense the
ubnormality & give command accordingly. Relay differentiate
normal & ubnormal condition which contactor can not.

In short if only contactor is connected in circuit.. in
case of ubnormal like OV or OC it will burn.. but if it is
connectedin coordination with relay.. relay will sense the
fault & give signal or command to contactor to trip

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