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Wiring for welder and plasma

Ultimabake

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Good morning

I currently have a 40 x 30 detached garage with a 100 amp panel. My question is is 6/2 romex too much? The welder is a Miller Multimatic 220 AC/DC and plasma is a old Bluepoint Snapon 230 50 amp.

thanks
 
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Terry D

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I look up the specs on the welder, looks like its 27.2 amps at 20% duty cycle for mig. 31.3 for stick. Going with the higher amp of 31.3x.45=14 amps. #12 would be fine. I would just run # 10 and put it on a 30 amp breaker
 
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pattenp

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If putting 50A breaker on #10cu with 50A outlet be sure to identify the circuit as welder use only. But in my opinion is to make it a general use 50A circuit and use #6cu.
Edit: I think Terry edited his comment from 50A to 30A breaker which is fine, but not sure what the plasma cutter calls for.
 
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Terry D

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If putting 50A breaker on #10cu with 50A outlet be sure to identify the circuit as welder use only. But in my opinion is to make it a general use 50A circuit and use #6cu.
Edit: I think Terry edited his comment from 50A to 30A breaker which is fine, but not sure what the plasma cutter calls for.

I did, it was a typo. I was thinking of the plug on the welder, it is a 6-50p. Is it okay to have a 50 amp receptacle on a 30 amp circuit? It might be the best to make it a general use 50 amp circuit
 
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TRWham

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I did, it was a typo. I was thinking of the plug on the welder, it is a 6-50p. Is it okay to have a 50 amp receptacle on a 30 amp circuit? It might be the best to make it a general use 50 amp circuit

Yes, as long as it is a single receptacle on an individual branch circuit (210.21(b)(1)), in which case the receptacle just needs to at least as big as the branch circuit rating. There's also an exception for welders that allows it to be smaller but I guess most 240 V welders provide a 6-50P.
 
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Ultimabake

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Ok thanks, can I run a dual breaker 50/30, 50 for plasma and 30 for the welder. This setup on a 6/2 line.
 
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pattenp

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Ok thanks, can I run a dual breaker 50/30, 50 for plasma and 30 for the welder. This setup on a 6/2 line.

The dual 50/30 breaker means two separate circuits. Why not just do the one 50A circuit using a 50A breaker with #6 to a 6-50R outlet to use for both the welder and plasma? Personally I prefer just wiring the circuit as general purpose instead of getting into reduced wire size for a welder.
 

u2slow

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I look up the specs on the welder, looks like its 27.2 amps at 20% duty cycle for mig. 31.3 for stick. Going with the higher amp of 31.3x.45=14 amps. #12 would be fine. I would just run # 10 and put it on a 30 amp breaker

^ This is what I'd do.

Unless OP has a bigger welder or plasma, its wasting money on copper and harder to install. Also splicing #6 for adding more receptacles needs costly connectors. #10 is easy to pigtail/daisy-chain with simple marrettes.

If you have extra #6... save it for another subpanel or a hot-tub. :)
 

pattenp

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^ This is what I'd do.

Unless OP has a bigger welder or plasma, its wasting money on copper and harder to install. Also splicing #6 for adding more receptacles needs costly connectors. #10 is easy to pigtail/daisy-chain with simple marrettes.

If you have extra #6... save it for another subpanel or a hot-tub. :)

That's against International Residential Building Code if subject to that code. Only 20A or less circuits are to have multiple receptacles.
 
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Ultimabake

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Ok I will make it a dedicated 6/2 line with a 50A breaker and run the welder and plasma when needed individually.

I have a 100 amp panel for the garage and I don't have any more space, hence the question about the dual breaker. I suppose I can come off the that panel with a sub-panel when I install my heat pump.
 

Terry D

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If you store the two machines next to each other, then one circuit to share both machines would make sense as long as it wouldn't be a hassle to unplug one and plug the other in to use it. I take you have only enough space to add one full size 2-pole breaker. If you panel accepts the quad breakers, then you could use a 30/50 quad and run dedicated circuits for each. Or use a quad for your shared welding circuit and your heat pump, but quads will only fit in panels that will accept tandems. The diagram inside the door should tell you.
 

u2slow

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That's against International Residential Building Code if subject to that code. Only 20A or less circuits are to have multiple receptacles.

Sure... if.

I'm not talented enough to run a plasma in one hand and weld with the other. But I'm pretty sure I can plug in two 1500W heaters and pop an 20A breaker. :thumbup:

EDIT: another idea is get a baby 4 space panel for like $30-40 and run it off a 60A/#6 in the garage panel. Put a circuit for each of the machines in the baby panel.
 

TTMotorsports

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On my old garage I had a 60 amp subpanel in the garage and had 2 30 amp circuits off it so I could run the 2 items at once and only have to run the bigger wire once and it was much cheaper and easier to do it that way.
 
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Ultimabake

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Terry D.....I miss wrote, I want to use a quad breaker and run the welder and plasma (not at same time of course) on the 50A and run the Heat pump on the 30A.
 
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