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Anonymous Poster #1

Power Contactor

04/19/2012 4:31 AM

Hai, every one.. i have given coil supply of 220v to contactor, it s energizes the coil but it giving sound... why it s cmg..?
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PWSlack
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#1

Re: power contactor

04/19/2012 4:58 AM

One of the possibilities is an unwanted solid located between the coil core and the armature that is preventing the armature from travelling to its maximum extent.

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V S Reddy
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#2
In reply to #1

Re: power contactor

04/19/2012 5:02 AM

thank u..!
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PWSlack
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#3

Re: power contactor

04/19/2012 6:23 AM

Another possibility is that it is a DC coil and AC is being supplied to it.

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kvsridhar
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#4

Re: power contactor

04/19/2012 7:44 AM

If the noise is a mild (100Hz) hum, barely audible, it may be due to :

1. Small particles of dust on the magnet surface

2. Magnetostriction

3. Poor design of shading rings

4. Too much contact spring force

If it is a very loud 'chattering' sound, it may be due to :

1. Broken/missing shading ring

2. Obstruction to the magnet movement (external body, shrunken bobbin, etc)

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Anonymous Poster #2
#5

Re: Power Contactor

04/19/2012 8:58 AM

Perhaps it likes the tune and just doesn't know the words.
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kvsridhar
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#7
In reply to #5

Re: Power Contactor

04/19/2012 9:40 PM

Only if it is humming. If the shading ring is broken, for example, it will sound like heavy metal

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NotUrOrdinaryJoe
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#6

Re: Power Contactor

04/19/2012 12:50 PM

It could also be an old contactor near its end of life. A few shorts in the windings cause excessive current and noise.

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ramvinod
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#8

Re: Power Contactor

04/21/2012 1:38 AM

What is the rated coil voltage?

If the applied voltage is less than the rated voltage then there is possiblity of humming.

Please measure the voltage after giving supply to the contactor.

If there is dust then also humming is possible.

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V S Reddy
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#9
In reply to #8

Re: Power Contactor

04/21/2012 2:08 AM

thank u all.... i found dust located in between coil core & armature core, after cleaning, it s working proper with out any sound....
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Users who posted comments:

Anonymous Poster (1); kvsridhar (2); NotUrOrdinaryJoe (1); PWSlack (2); ramvinod (1); V S Reddy (2)

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