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benotype
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Join Date: Nov 2009
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Electrical Distribution Source

10/17/2011 12:41 PM

I have an electrical distribution diagram. On the drawing a 4x 20A mg Curve C breaker supplies power to a switch rated at 4X 50A (earthing device protection 0.3A). Is this connection diagram correct? I am of the opinion that the 4 x 20A should be higher than 4 x 50A switch to ensure proper operation and to avoid overloading on the breaker. Please I stand to be corrected. Can anyone elaborate in more details.
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wareagle
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#1

Re: Electrical Distribution Source

10/17/2011 6:34 PM

What is the amp load on the breaker?
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Tornado
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#2

Re: Electrical Distribution Source

10/17/2011 10:20 PM

If the breaker rating were greater than the switch rating, then the breaker could let through enough current to damage the switch. Also, the breaker rating must take into account the ratings of the wiring and the load. There is no problem with the switch rating being higher, other than it may have cost more than a 20A switch.

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harjeetsinghengg
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#3

Re: Electrical Distribution Source

10/18/2011 3:34 AM

SINCE, BREAKER SHOULD HAVE HIGHER ACCEPTABLE RATING FROM ITS DISTRIBUTION CIRCUIT. BUT IN THIS CASE I GUESS SWITCH CAN BE ADJUSTED ACCORDING TO ALLOWABLE LEAKAGE CURRENT SO, I DON'T SEE ANY TECHNICAL PROBLEM.

AND 4X50A RATING CAN BE CONSIDERED FOR TRANSIENT CONDITIONS ONLY.
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PWSlack
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#4
In reply to #3

Re: Electrical Distribution Source

10/18/2011 7:28 AM

Please turn off Caps Lock; there is no need to SHOUT.

Nothing in the original posting is in any way related to earth leak current.

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PWSlack
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#5

Re: Electrical Distribution Source

10/18/2011 9:46 AM

There is nothing wrong in putting a switch rated at 50A in a circuit that is overload-protected at 20A.

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