What is the difference between Relay and Contactor

Answer Posted / vikrant patel

First Clear Relay Means
1. Protective relay
2. Control Relay.

If talking about Protective relay (Example: over current
Relay, Electronic motor protection relay..etc)
so protective relay is for Protection of circuit
and functionally different from contactor.
they have only potential free contact at output which can
be used in control circuit.

if talking about control relay
1. Power relay (which have Change over contact with high
current capacity)
2. Solid state relay
3. Simple control relay. (Which have Change over contact
with low current capacity call SPDT)

This all relay has functionally similarity with contactor
that they are electromagnetic device (except SSR) but
difference
- relay have changeover contact (NO, NC& Common) while
contactor have power contact NO) & auxiliary contact (NO or
NC).

Main difference is

- Contactor is used to Control power Circuit while relay
are used for control circuit (except Power relay which is
now a days introduce for DC/High voltage application).

Is This Answer Correct ?    117 Yes 11 No



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