Welder Receptacle

[hammlm]

Hello;

I'm going to get my welder (Hobart Handler 175) fired back up again after a hiatus since moving.

I intend to pipe (EMT) from a sub-panel to a 4" SQ Deep Box with appropriate cover for installation of a NEMA 6-50R.

Distance of Pipe Run is less than 20'.

I'm planning to use #12 THHN for Line (black/red) and the grounded conductors. I'm planning to protect with a 2-pole 20A breaker.

I will also have another 120V circuit running in this pipe (passing through). Since I will be pulling a green wire for device grounds on these other receps, should I use the Green wire to connect to the NEMA 6-50R, or should I pull a (separate) (white?) wire?

I feel like this should be obvious (use the green, stupid) -- but I am doubting myself for some reason.

Anything wrong, or that I could do better?

 

[hammlm]

Just thought I would add this, since I didn't make it clear.

I see no reason or opportunity for me to upgrade my welder. While I would love to, I just don't see it happening.

If I did, I could change out the wire / breaker at that time (since it's piped).

Thank you in advance.

 

[wyliesdiesels]

Hello;

I'm going to get my welder (Hobart Handler 175) fired back up again after a hiatus since moving.

I intend to pipe (EMT) from a sub-panel to a 4" SQ Deep Box with appropriate cover for installation of a NEMA 6-50R.

Distance of Pipe Run is less than 20'.

I'm planning to use #12 THHN for Line (black/red) and the grounded conductors. I'm planning to protect with a 2-pole 20A breaker.

I will also have another 120V circuit running in this pipe (passing through). Since I will be pulling a green wire for device grounds on these other receps, should I use the Green wire to connect to the NEMA 6-50R, or should I pull a (separate) (white?) wire?

I feel like this should be obvious (use the green, stupid) -- but I am doubting myself for some reason.

Anything wrong, or that I could do better?

First off, white(neutral/grounded conductor) and green(EGC aka grounding conductor) are 2 different animals and shouldnt be confused. A neutral shouldnt be used in place of a ground and vice versa. Ground wires should always be colored green or reidentified with green tape. Neutral should always be white or gray.

Second, because u have more than 3 CCC(current carrying conductors) in a raceway derating factors need to be considered. However, the factor is 80% and with the 30a ampacity of #12 THHN the final ampacity is 24a, so youre good.

Finally, welder circuits are sized based on duty cycle. The Hobart Handler 175 has a 30% duty cycle @ 240v 60hz input with 19.5a load. The factor for 30% duty cycle is 55%. So your 20a circuit should be fine.

 

[hammlm]

Thanks for the information.

When I said "or should I pull a (separate) (white?) wire?".. I should have added "and tape it green." I stopped my sentence before I said that.

Based on what I read in the response above, it would seem that I'm good to just connect the one green ground wired that I am pulling to the NEMA 6-50R -- as I showed in the diagram

Thank you, appreciate it.

 

[pattenp]

Thanks for the information.

When I said "or should I pull a (separate) (white?) wire?".. I should have added "and tape it green." I stopped my sentence before I said that.

Based on what I read in the response above, it would seem that I'm good to just connect the one green ground wired that I am pulling to the NEMA 6-50R -- as I showed in the diagram

Thank you, appreciate it.

Seems picky but by NEC insulated grounding conductors smaller than #4 are not to be reidentified by marking/taping them green. The insulation needs to be the correct color.

 

[alfredeneuman]

Seems picky but by NEC insulated grounding conductors smaller than #4 are not to be reidentified by marking/taping them green. The insulation needs to be the correct color.

....... and it only applies to conductors in conduit, not cables.

Since you're using conduit you're out of luck.

 

[sberry]

There is not really a reason not to use a 30A breaker here. Most people probably cant tune the machine wide open at the start but rated is 24A. Personally would use a 10 wire here, a bit for performance but mostly because it fits the recept way better and some brands only list down to 10 for it.

 

[alfredeneuman]

The manual recommends a Maximum 20A breaker or Standard Fuse.

 

[sberry]

The manual recommends a Maximum 20A breaker or Standard Fuse.

On what? A Hobart 175 has a 50A plug. Legal for a 50A welder circuit. In fact can be a 12 wire on a 50 brkr.

 

[pattenp]

....... and it only applies to conductors in conduit, not cables.

Since you're using conduit you're out of luck.

Identifying of other conductors in a multiconductor cable is only allowed where maintenance and supervision ensure that only qualified persons service the installation. In a home DIY situation you should not be marking other conductors in a cable as a EGC.

 

[alfredeneuman]

Identifying of other conductors in a multiconductor cable is only allowed where maintenance and supervision ensure that only qualified persons service the installation. In a home DIY situation you should not be marking other conductors in a cable as a EGC.

You're quite right.
I misread it as grounded conductor instead grounding. :tard:

 

[teamextreme]

On what? A Hobart 175 has a 50A plug. Legal for a 50A welder circuit. In fact can be a 12 wire on a 50 brkr.

OK, I'm a little confused here. Motors have totally different rules for conductor and breaker sizing and can result in things like #12 on a 40a breaker, which throws people off, but I've never heard of large equipment circuits like this having similar allowances. Now you made me recheck the manual and it does say max 20a breaker, but calls for a 50a recep. I ran #6 romex from a 40a breaker to a 50a recep for my Hobart 175. Assuming you didn't know the welder you are plugging in, and it's a general use 50a outlet, wouldn't it require #6?

 

[sberry]

Where does it say 20A for this machine? I believe the manual may be for a 135/175 and its being read for the small machine. The 175 comes with 50A welder plug and lists 14 wire with 30A breaker as a minimum wire max breaker but,,, this is only for the 14 wire, once it goes to 12 it can be on a breaker to 50. The owners manuals are bad in this respect, they are written for electricians and they should have a lay explanation with a recommendation over code.

Ok, I looked and yes it is listed that way but its somewhat misleading. That is when the minimum wire size is used. The machine has a 12 cord and a 50A plug.

 

[sberry]

They fiddled with the manuals during that time, if you look the grounding conductor is listed as a 12 min while the currents may be 14. The 180 which was the next model didn't load but I looked at a 187 and they had changed it by then to what it is now.

 

[sberry]

At any rate the machine is listed to plug in to the outlet with the plug comes with it provided the circuit has adequate wire size to meet short circuit standards.

 

[sberry]

We found an error in one of the Miller manuals a while back, I believe it has been fixed. Its been a while and I cant remember exact but it was something with this listing, might have been the grounding conductor.
Miller got a new engineer or 2, they are great engineers but a couple of them are not super familiar with codes and people have got a bit of confusion from them on the phone regarding breakers.

 

[wyliesdiesels]

Where does it say 20A for this machine? I believe the manual may be for a 135/175 and its being read for the small machine. The 175 comes with 50A welder plug and lists 14 wire with 30A breaker as a minimum wire max breaker but,,, this is only for the 14 wire, once it goes to 12 it can be on a breaker to 50. The owners manuals are bad in this respect, they are written for electricians and they should have a lay explanation with a recommendation over code.

Ok, I looked and yes it is listed that way but its somewhat misleading. That is when the minimum wire size is used. The machine has a 12 cord and a 50A plug.

Manual seems fine to me.

http://www.hobartwelders.com/om/0900/o944g_hob.pdf

Those welders are 20% duty cycle with 20a input.

Based on T630.11(a) u could use #14....

http://m.ecmweb.com/qampa/code-qa-45

 

[sberry]

No one thinks 14 is a great idea, as much for poor terminations as anything. I do realize the 175 is rated a pinch less than the 210 or 211 but they fall in to the same general class regarding wiring for the most part. The only difference being the breaker on small wire, there must5 be a fuzz difference in NEMA standards here, its a pretty fine line.
My personal feeling is a 10/30 for them, I always want to give these little machines all the help they can get. Its never problem to turn them down but they hit the ceiling pretty fast.

 

[sberry]

Assuming you didn't know the welder you are plugging in, and it's a general use 50a outlet, wouldn't it require #6?

This is true to some extent and depending on the machine would verify the wire.
his is just some general ramble here, so,,, there are a couple cases where it could be underwired and lets assume its legal but the 14 could be there but in that case would need to be protected by the max breaker listing, which would be a 20 for a 175 or a 30 for a 211. In this case the incoming wire is actually lighter tan the cord on the machine.
These units come with a wire size one bigger than the demands, reason being is to allow them on larger common 50A welder circuits.
For the sake of this discussion we are talking about factory wired machines that come with 50A end. The only ones that require a wire larger than 12 are the 250 class feeders. Some of them with high duty cycles and screaming outputs need an 8, this would not be an issue at home, this is in production with special gas and they even need the guns changed out, it will burn up the factory gun.
Basically any welder you can plug in wont overheat a 10 and most wont overheat a 12 but we get back to following duty cycles and termination issues but you wont burn the shack down with a buzzer on a 10 cable or cord.

 

[sberry]

The Lincoln 225 coms with a 12 cord, 50A plug for a draw of 48A, 2x the same as the 175 Hobart, same cord. In the foot notes of the Linc it specs the 12 allowed for the circuit needs to be single circuit in pipe with notes that if it is a cord or cable needs to be sized up.