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to protect or to calculate the operating conditions of an electrical system and to camand circuitbreaker to trip in any fault detection.relay is the one which detects the abnormal condition of the circuit and signals the circuit breaker to trip(open).....

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10y ago
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12y ago

The auxiliary contact is connected in parallel with the 'start' pushbutton switch in the control circuit. When the 'on' button is pressed, the auxiliary (together with the main contacts) close, bypassing the 'on' button, and keeping the relay's operating coil energised, and maintaining the contacts in the closed position. A 'stop' pushbutton switch must be placed in series with the 'start' switch in order to break the control, de-energising the operation coil, and opening the main and auxiliary contacts.

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13y ago

They can be used for electrical loads with heavy current that need to be switched on and off. They are also used for remote switching applications.

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12y ago

A contactoris an electrically controlled switch used for switching a power circuit.

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13y ago

They can be used for electrical loads with heavy current that need to be switched on and off. They are also used for remote switching applications.

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Q: What is the purpose of a contactor and a relay?
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What is the difference between an definite purpose contactor and a lighting sontactor?

A definite purpose contactor is designed (and rated) for a specific load. So a lighting contactor is one example of a definite purpose contactor. A motor starter contactor is another example. So, a lighting contactor is a definite purpose contactor, but a definite purpose contactor is not necessarily a lighting contactor (it might be a motor starter, for instance).


How do you put definite purpose contactor?

Depends on where you want to put it! Assuming, that you're asking ~how you'd "install" a Definite purpose contactor.


What is a contactor for a Central Air Unit?

The relay actuated by the thermostat which starts and stops the compressor and condenser fan in the outdoor unit.


What is the different between contactor and relay?

A contactor, as far as being used to start a motor or the like, is in essence, a relay. A coil is energized and the normally open contacts from the contactor close (normally 3 contacts for an AC motor) and the motor starts. Do I understand your question? Or are you trying to decifer the difference between the coil of a relay and the contacts of a relay?


What is the function of phase sensing relay?

A phase sensing relay monitors all three incoming phase legs at once. With the relay the operator has the ability to set the trip points in a percentage of incoming line voltage. If the voltage in any of the monitored legs falls below the operators set point the relay will trip and take the monitored device off line. If it is a motor being protected, the auxiliary contacts on the phase sensing relay will change state and its N.C. contact will open. The motor's contactor coil is in series with this auxiliary contact so with the stoppage of current flow to the magnetic contactor's holding coil, the contactor opens cutting off the supply to the motor.

Related questions

What is the difference between an definite purpose contactor and a lighting sontactor?

A definite purpose contactor is designed (and rated) for a specific load. So a lighting contactor is one example of a definite purpose contactor. A motor starter contactor is another example. So, a lighting contactor is a definite purpose contactor, but a definite purpose contactor is not necessarily a lighting contactor (it might be a motor starter, for instance).


What is the part of the contactor that gets magnetized by the relay coil is called what?

The part of the contactor that gets magnetized by the relay coil is called the armature or plunger. This is the component that moves when the relay coil is energized, causing the contacts to close or open depending on the design of the contactor.


How do you wire a relay to a motor contactor?

One way is to use the auxiliary contacts on the motor contactor to close a separate source supply to drive an auxiliary relay.


How do you put definite purpose contactor?

Depends on where you want to put it! Assuming, that you're asking ~how you'd "install" a Definite purpose contactor.


Can you replace an 3 phase solid state relay with a contactor on a 3 phase heater?

Not without other modifications. The circuits used to turn the solid state relay on will not be suitable for turning a contactor on.


How relay is used to control induction motor?

If you want to control induction motor using a control relay give neutral directly to the one point of coil of relay & one point of coil of contactor then give control supply through push button to second point of coil of relay. use one NO point of relay and give supply to coil of contactor. and also use one NO of contactor for holding the contactor & take OFF (NC) in the starting to stop motor after complition of work. It is jut like an Direct On-line starter.


What device is the only load in the control circuit of a condensing unit?

I think that would have to be some relay or contactor coil for a fan, compressor or relay contacts.


If condencer contactor goes out...will it stop blowing cold air?

this is most likely a relay under the hood.


What is a electrical contactor for?

An electrical contractor does the wiring for homes and businesses. They install the wiring and electrical components needed to run electricity. The question asks about a contactor, not a contractor. A contactor is a type of heavy duty electrical relay for using smaller voltages to control much larger voltages.


What is a magnetic contactor protection device?

A magnetic contactor protection device is a device that protects the magnetic contactor from damage due to overload, short circuit, or other electrical faults. It is used in electrical systems to ensure the safe and reliable operation of the contactor.


How does an auxiliary contact work?

The auxiliary contact is to be utilized for interlocking of another relay or contactor or indication signal from another equipment.


What is a contactor for a Central Air Unit?

The relay actuated by the thermostat which starts and stops the compressor and condenser fan in the outdoor unit.