what is an electrical contactor used for?

Answer 1

An electrical switch designed for opening and closing a circuit frequently. Example: relay contactor for keying a transmitter.
When a relay is used to switch a large amount of electrical power through its contacts, it is designated by a special name: contactor. Contactors typically have multiple contacts, and those contacts are usually (but not always) normally-open, so that power to the load is shut off when the coil is de-energized. Perhaps the most common industrial use for contactors is the control of electric motors.

A contactor is a large relay, usually used to switch current to an electric motor or other high-power load.
Large electric motors can be protected from overcurrent damage through the use of overload heaters and overload contacts. If the series-connected heaters get too hot from excessive current, the normally-closed overload contact will open, de-energizing the contactor sending power to the motor.

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Answer 2

Hey a electrical contactor is nothing but a switching circuit, which is being used to make required contacts & also avoide any danger in case of power failure. Lets talk about DOL(direct online start) motor which uses a contactor and relay. The contactor provides the necessary connections & helps in starting the motor, but in case of power failure the circuit is being cut through these contactors. So this was all about Contactors....hope your problem would be solved.

Answer 3

My experience with contactors (relays) involves using a low, single phase voltage switch (such as a normal household 120VAC) to control 3 phase, 220 or 400 VAC to a large motor or heater.
These contactors have three poles or contacts, which are normally open, with each phase of the higher voltage connected to each pole. The other side of the contactor poles is connected to the motor. The coil, which pulls the contacts together, is simply a 120 VAC magnetic solenoid.
Contactors can have multiple contacts and can be single or double throw (normally closed on one set of contacts and normally open on the other.)
This procedure eliminates the need for expensive, high voltage, 3 Phase switches and the associated wiring and it's considerably safer, more reliable and simpler to trouble shoot.

Answer 4

To remotely switch a large load with a small current.
The contactor is just an electric switch - you provide power to the coil which moves the contacts together to switch a larger current.

Just like a relay but switches power.

Answer 5

For closing and opening an electric circuit.
The electrical contactor may be supplied from a separate supply to the supply it is opening or closing.
The supply to the contactor may be d.c. from a battery.

Answer 6

A contactor is identical in function to a relay. (Actually, that's all it is--a really big relay.) It is often used to remotely control a motor or other device.

Answer 7

It's a sort of relay.
A small current controls a solenoid, which operates contacts able to switch a large amount of current.

Answer 8

To energize something like an air conditioning unit,. usually with a lower voltage coil

Answer 9

To sort out electrics.