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#58732 - 11/15/05 06:46 PM Derating wire plus voltage drop
bot540 Offline

Registered: 09/14/04
Posts: 177
Loc: Vernon Hills, IL
If you already upsized the wire for voltage drop would you have to further derate the wire if you have more than 4 current carrying conductors? Do the calculations compound?
Jesus may have been a capenter,but God was an electrician.Genesis1:3

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#58733 - 11/15/05 07:22 PM Re: Derating wire plus voltage drop
Cow Offline

Registered: 07/01/05
Posts: 33
Loc: Hermiston, OR

#58734 - 11/15/05 08:44 PM Re: Derating wire plus voltage drop
Bob Offline

Registered: 02/05/02
Posts: 182
Loc: Mobile, AL, USA
First caculate the load.
Size the wire for the load.
Derate per the table 80%. This will give you a larger conductor. Caculate the VD using this conductor.
If you have to go larger you do not derate again.


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