why the 125% rule for transformer conductors?

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bigpapa #184490 02/11/09 05:35 PM

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Originally Posted by bigpapa

Is this conductor derating because of higher temperatures in the transformer?

No, the 125% is to accomidate the inrush current that happens when a transformer is energized.

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Entire Thread
Subject	Posted By	Posted
why the 125% rule for transformer conductors?	bigpapa	02/11/09 09:03 AM
Re: why the 125% rule for transformer conductors?	mr_electrician	02/11/09 09:35 PM
Re: why the 125% rule for transformer conductors?	Eddy Current	02/12/09 02:39 PM
Re: why the 125% rule for transformer conductors?	jay8	02/13/09 06:42 AM
Re: why the 125% rule for transformer conductors?	LarryC	02/13/09 05:35 PM
Re: why the 125% rule for transformer conductors?	leland	02/13/09 05:59 PM
Re: why the 125% rule for transformer conductors?	mr_electrician	02/13/09 08:16 PM
Re: why the 125% rule for transformer conductors?	twh	02/14/09 04:48 AM
Re: why the 125% rule for transformer conductors?	bigpapa	04/18/09 10:55 AM
Re: why the 125% rule for transformer conductors?	mikesh	04/20/09 06:34 PM

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ECN Forum Forums Code Related Discussion Canadian Electrical Code Topics why the 125% rule for transformer conductors?