Changing 240v 20amp to 50amp for Welder

[Whiskeymike]

I'm about to purchase a new Hobart 190 Mig welder and I need an outlet that will support it. Currently, out of my panel is a 240v 20amp drop to a box/recepticle about 6 inches below. My plan is to change the double throw 20 amp breaker to a 50 amp breaker. Replace the wiring with 6awg and replace the recepticle with 6-50 recepticle. I have a few questions.

1. Does the red/black wires make any difference where they go on the breaker or the recepticle (of course, beyond the ground which goes to the middle screw on the recepticle labeled ground)?

2. Since this is the primary and only panel, the neutral bar is also the ground bar, and the green ground wire should be connected to that? (doesn't matter, but preferably next to the breaker that it corresponds to?)


I provided a couple pictures in case it's handy. Sorry the one is really blurry.

 

[s10xtremist]

1. No.

2. Yes.

 

[pattenp]

Doesn't matter on the Black and Red to the breaker and outlet. The ground is connected to the neutral/ground bar. Doesn't matter where on the bar it goes, just don't pair it in a hole with a neutral. Put it with another single ground wire or use an empty hole.

 

[Whiskeymike]

Perfect, thanks guys.

Also, I plan to turn off the feed outside the building, and then in the panel as well. What's the best way to test everything is off? Connect leads to the two big leads coming into the box? or the connection to a breaker and the ground bar?

 

[hilld]

Perfect, thanks guys.

Also, I plan to turn off the feed outside the building, and then in the panel as well. What's the best way to test everything is off? Connect leads to the two big leads coming into the box? or the connection to a breaker and the ground bar?

Use a volt meter, at the very minimum you should have one of these before doing any electrical work.

 

[Aceman]

Since you're using THHN and not Romex, #8 is fine for 50 amps. Use a #10 green for your ground.

 

[Speedy Petey]

My question is WHY would you "change" whats there??? You may need it someday, even if you think you never will. It's not like it's a long run or anything. And it's not like you're out of breaker space either.
Just add a new 50A receptacle.

 

[Charles (in GA)]

My question is WHY would you "change" whats there??? You may need it someday, even if you think you never will. It's not like it's a long run or anything. And it's not like you're out of breaker space either.
Just add a new 50A receptacle.

As I read thru this thread, I was thinking the same thing. Why bother removing any of what you have, just install a new box and breaker and wire and be done with it. You might find a use for the other receptacle, such as a 240v portable air compressor.

Charles

NEMA 6-50, 6-20 (accepts 15 & 20 amp plugs), and L14-30 under my panel. Got most all bases covered.

 

[Tigwldr]

Im not familiar with this particular machine but why would you need 50 amp service for it? I cant find a spec sheet on it right off hand but I run several larger machines off a 30 amp service. I don't think you need anything that large unless your just looking for the future of upgrading.

 

[volleyball]

He is running a couple feet of wire. Go big or go home. Breaker prices are the same, a couple more dollars for wire.

 

[Whiskeymike]

Use a volt meter, at the very minimum you should have one of these before doing any electrical work.

Yep, got one. Just asking where I connect the leads to be sure that I test it correctly. At least to me, it doesn't appear as simple as testing a recepticle at the end of the circuit.

 

[Whiskeymike]

My question is WHY would you "change" whats there??? You may need it someday, even if you think you never will. It's not like it's a long run or anything. And it's not like you're out of breaker space either.
Just add a new 50A receptacle.

Yep, I'm debating the same thing. It just doesn't seem like 240v at 20 amps is all that useful. I've had the shop for a year and haven't found any tools so far that require 240@20, so I figured I might as well leave the empty space for future expansion.

With that thought, I started going down the path of adding the 50 amp circuit and upgrading the 20amp to 30 amp where I have tools that require that service level. But then the project get's bigger and more complicated.

Maybe I'll add it as new. I already have the box, etc..

 

[Whiskeymike]

Im not familiar with this particular machine but why would you need 50 amp service for it? I cant find a spec sheet on it right off hand but I run several larger machines off a 30 amp service. I don't think you need anything that large unless your just looking for the future of upgrading.

The spec for the machine is 240 at 30amp, but uses a 6-50 plug. After reading previous debates here, talking about concerns of confusing people with a 50 amp plug with 30 amp service, or replacing the end male plug on the welder with a 6-50 plug, etc.. it seemed like the difference in cost for the wire and breaker was a few dollars, so I might as well just do it.

 

[lametec]

Many people have used their HH187 on 20A circuits without issues. I doubt you'll trip the 20A breaker under normal use with your HH190.

 

[hackwelder]

The spec for the machine is 240 at 30amp, but uses a 6-50 plug. After reading previous debates here, talking about concerns of confusing people with a 50 amp plug with 30 amp service, or replacing the end male plug on the welder with a 6-50 plug, etc.. it seemed like the difference in cost for the wire and breaker was a few dollars, so I might as well just do it.

Don't think that is right, the spec is 20.5 amps @230V and unless the welder is set for max power it will pull considerably less than 20 amps. FWIW I have a similar Miller 172 that is spec'd at 20A@230V, have run it on 30A dryer outlets at 3 different places I've lived over the years and never had a problem or popped a breaker.

(my Miller has a kiln plug and I did not change it, instead made an extension cord with a dryer plug to a kiln receptacle using wire as specified in the Miller owners manual)


Hobart 190 specs

 

[ishiboo]

Don't think that is right, the spec is 20.5 amps @230V and unless the welder is set for max power it will pull considerably less than 20 amps. FWIW I have a similar Miller 172 that is spec'd at 20A@230V, have run it on 30A dryer outlets at 3 different places I've lived over the years and never had a problem or popped a breaker.

(my Miller has a kiln plug and I did not change it, instead made an extension cord with a dryer plug to a kiln receptacle using wire as specified in the Miller owners manual)


Hobart 190 specs

They probably recommend a 30A breaker, but the wire ampacity is figured for 20A.

I'd try it on 20A, if it blows the breaker upgrade to a 30A breaker. It's a welder receptacle after all.

 

[Whiskeymike]

Wow, thanks. I was going off the conversation in this thread. http://www.garagejournal.com/forum/archive/index.php/t-160310.html

Maybe I don't have to change it.