How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask AssuredElectrical Your Own Question
AssuredElectrical, Master Electrician
Category: Electrical
Satisfied Customers: 4241
Experience:  Contractor-42+ Years in the ElectricalTrade
Type Your Electrical Question Here...
AssuredElectrical is online now
A new question is answered every 9 seconds

I am doing a job Farm Equipment shop and the owner wants to

Customer Question

I am doing a job for a Farm Equipment shop and the owner wants to add a 30A Heliarc welder receptacle but he wants to use a 50A receptacle, 50 amp wire and a 50A Circuit breaker and I beleive he can use a 50A receptacle but he must use wire and Circuit
Breaker that is 125% of the receptacle. which would be just under 65A am I right?
Submitted: 2 years ago.
Category: Electrical
Expert:  AssuredElectrical replied 2 years ago.

Welcome. My name is ***** ***** would be glad to assist.

What is the information on the welders nameplate as far as all amperage requirements?

Let me know and we can continue,


Customer: replied 2 years ago.
30 Amps
Expert:  AssuredElectrical replied 2 years ago.


Is that all it has on the nameplate?

Does it have a maximum and Minimum?

There are several sections with information, can you get a picture and post?

Customer: replied 2 years ago.
No I am not at the shop the electrician is but he tells me that it is a 30 Amp AC 240V single phase, Duty Cycle 200, 1 Hour rating at 60% and a 32 Amp DC output.
Expert:  AssuredElectrical replied 2 years ago.

Ok, thanks.

You are allowed to a maximum of 200% of the rating as you can see below in the code.

630.12 Overcurrent Protection
(A)For Welders. Each welder shall have over current protection rated or set at not more than 200 percent of I1max. Alternatively, if the I1max is not given, the over current protection shall be rated or set at not more than 200 percent of the rated primary current of the welder.

So, the 50 amp would most likely operate the welder fine.

Customer: replied 2 years ago.
That is not what I am asking. I am asking if in order to install a 50 Amp receptacle in this case must I run 65 amp wire and install a 65 Amp circuit breaker
Expert:  AssuredElectrical replied 2 years ago.

I am missing information or something here apparently.

The receptacle is for the welder, is it not?

If the receptacle is rated at 50 amps, you cannot supply it with 65 amps.

The maximum OCPD can only be 50 amps on the receptacle.

There is no need to up to 60 amps on the circuit unless you think the 50 is inadequate.

I think you are wanting to size the 50 amp based as continuous duty as in other areas of the code.

But, the code specifically states:

Even under high-production conditions, the loads on transformer arc welders are considered intermittent.

So, that doesnt come into play with welders, only the 200 percent maximum previously posted is applied