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#93751 - 06/08/05 08:59 PM art 630
OreElect Offline

Registered: 03/05/04
Posts: 96
Loc: Salem,Oregon.USA
Hi all.
Question for load calculation.
Ive got 2- 50 amp 480 volt 1 ph 70% duty welders.
Using the multiplier .84 for the 70 % duty cycle, I am to use this on the first 2 welders correct?
Also,if using a 3rd welder,using the 85 %,is this 85% of the .84 multiplier.
Your opinions appreciated

2014 / 2011 NEC & Related Books and Study Guides
#93752 - 06/08/05 10:45 PM Re: art 630
gfretwell Offline


Registered: 07/20/04
Posts: 9025
Loc: Estero,Fl,usa
That's the way 630.11(B) reads to me

(B) Group of Welders. Conductor ampacity shall be based on the individual currents determined in 630.11(A) as the sum of 100 percent of the two largest welders, plus 85 percent of the third largest welder...
Greg Fretwell


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