Relay vs Contactor , what are the differences.


A Relay is an electrically operated switch, it basically consists of an electromagnetic coil which builds up a magnetic field when current is passed through it. This magnetic field is used to operate the relay contacts to an OFF or ON state.
A Contactor is an electrically operated switch, it basically consists of an electromagnetic coil which builds up a magnetic field when current is passed through it. This magnetic field is used to move the contactor contacts into an OFF or ON state.

So what is the difference between a relay and a contactor.
In the most simplistic terms, a contactor is a relay is used to switch a large amount of electrical power through its contacts.

Other notable differences are stated below.
1)    Relays tend to be for logic switching while contactors are for Power switching
2)    Relays don’t come with auxiliary contacts while many contactors have provision for auxiliary contacts
3)    Relays are commonly used for single phase applications while Contactors are mostly used for 3 phase applications
4)    Relays don’t really come with safety features like arc suppression and spring-loaded contacts while some contactors come with arc suppression and all contactors come with spring-loaded contacts to ensure that all poles are opened at the same time.
5)    Most relays come with NO/NC configurations on the same relay while contacts are NO and closed only when power needs to be switched on.
6)    Relays have a maximum current of around 20A while some contactors can carry up to 12,000A



Comments

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