Answer / chandru_williams

contactors are used to make or break a circuit.Its
unconditional.

But relays can be used for conditional switching or
breaking of a circuit.

Answer / kishor mochi

it is depend only load and load current.
if connected load is less then 5A,that case we are use
relay.
Exactly opposite side, if connected load equal lot grater
then 5A, that case we are use contactor.

Answer / sudarshan patwal

Relay current rating is max. 5A But Condactor current
rating is more than 5A.
Relay has one comman, 1NO & 1NC (Means comman is same for
NO & NC) which Condactor has seperate comman+NO & comman+NC.

Answer / khajamian

Contactors are devices consists of E shaped
electromagnectic core with winding are mainly used for NO
and NC connections which means making and braking of
circuit... we can split the flow of current by using
contactors...DC contactors and ac contactors are also
available.. it is used for high rating ... above 110v ac
and dc... But relays are also used for NO and NC changes
i.e making and breaking of circuits but especially for
remote or distant operation.. using 110 v ac supply..it
also consists of coil but absence of electromagnetic core..
there are several types of relays ..ex: industrial relay,
electromagnetic relay... etc

Answer / s. rahimzadeh

Contactors take palce against the circuit breakers (not
relays). Contactor acts like a circuit breaker and
similarly can get its command from a relay. Relays are used
for detecting the conditions which the circuit switch
(Circuit breaker or Contactor) should cut the circuit.

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