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lalit_nawada
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Join Date: Apr 2009
Location: CG
Posts: 64

Contactors

05/02/2009 9:48 AM

What is the difference between general contactors & hoisting duty ontactors?
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Tippycanoe
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#1

Re: Contactors

05/02/2009 10:15 AM

A general contractor may hire any kind of sub-contractor. This includes but not limited to lifting contractors, who may in turn hire cranes, riggers, scaffolding, operators and technicians, etc..

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Anonymous Poster
#2
In reply to #1

Re: Contactors

05/02/2009 3:09 PM

The question asks about contactors not contractors
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Tippycanoe
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#5
In reply to #2

Re: Contactors

05/05/2009 9:53 PM

OOps, !!

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Paulusgnome
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#3

Re: Contactors

05/02/2009 7:11 PM

Any contactor can be used for either purpose, but the current ratings are lower when used in 'inching and plugging' mode as they are in cranes and hoists.

For any general motor starting duties, select your contactor on the basis of the AC3 rating.

For inching and plugging, select the contactor on the basis of the AC4 rating. Your contactor supplier will be able to supply this information.

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JRaef
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#4
In reply to #3

Re: Contactors

05/04/2009 9:07 AM

Unless you are in the US, where you simply select a NEMA rated contactor which is essentially the equivalent of an AC-4 already.

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