Welder Overcurrent Protection

[Shoe]

I have a client who has standardized on using 60A, 480V, 3-phase receptacles and plugs for all their welding units. These are wired 60 amps back to a 60/3 breaker.

If the welder is a smaller unit (i.e. less than 30 amps max input current), are they at risk of violating 630.12 (200% I1max) or am I not understanding this part of the code?

I've seen many set ups in manufacturing where they will do this type of thing and string multiple welding receptacles on a single 60 amp circuit.

 

[steve66]

Do the welders already have a cord and plug connected when they are bought? If so, are they cutting off the cord and installing different plugs?

Steve

 

[Shoe]

Yes, they are installing their own plug on the welder compatible with their universal outlet.

 

[steve66]

In my opinion, if they are cutting a plug off the welder so they can install a higher amp plug, that's a violation of the listing of the listing of the welder (the UL listing, for example).


If a welder came with a 20 amp plug, for example, and they made an adapter by putting a 20A receptacle on a cord with a 60a plug on the other end, that would also be a violation sinice 20 amp receptacles are only allowed on 15 or 20 amp branch circuits.

 

[zbang]

And, of course, if it came with a 20a plug, it's probably 12g cable. Not so good with a 60a breaker- kinda blows past 400.5, 400.13, and especially 240.5.