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

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...

I have moved this to the NEC forum. Please post your comments here:

https://www.electrical-contractor.net/ubb/Forum2/HTML/002126.html