SJOOW For Welder: What gauge?

[PCustoms]

I've got a small 220v MIG welder I need to move around my garage and maybe even outside. The spec sheet says 20A, I am pretty sure I read FLA=26A somewhere.

I have a dryer outlet located within 25 feet of the panel, protected by a 30A breaker and fed by 10/4 romex.

My original plan was to get a 50' 8/3 pre-made extension cord, or get a length of 10/4 SJOOW and make one. Was asking around at work today for the opportunity to purchase (we buy multiple huge rolls) and it was suggested that 8 gauge is overkill.

I'm playing around with some online calcs tonight and it seems like 10 gauge is adequate for over 75ft (25 from breaker, 50 cord), in fact I can go 150ft and still not see a 5% drop.

What am I missing here? Does an outlet need to be factored in somehow? I have no issues running 8 if it makes a big difference, but wouldn't mind saving some money if I can run 10 gauge.

 

[Aceman]

I would use 10-3 SO. It has a thicker jacket than SJ.

 

[theoldwizard1]

I would use 10-3 SO. It has a thicker jacket than SJ.

True, but if there was more than a 10% difference, I would buy the SJOOW.

10/3 would be fine for 50'. Welders typically have a low duty cycle (<50%) so you can use a slightly smaller cable. Extension cords are typically "upsized" 1 gauge compared to permanent wire.

If you wre going to pull close to 30A continuously, I would go 8/3.

You don't need a neutral if you are only using the extension for 240V.

 

[PCustoms]

You don't need a neutral if you are only using the extension for 240V.

I am aware, but hadn't decided the best way to transition from the dryer outlet with neutral to the welder. Can I safely just pull off the 2 hots and ground, or should I make a short whip (dryer plug to welder plug) where I bond the neutral and ground?

 

[Norcal]

I am aware, but hadn't decided the best way to transition from the dryer outlet with neutral to the welder. Can I safely just pull off the 2 hots and ground, or should I make a short whip (dryer plug to welder plug) where I bond the neutral and ground?

NO! NO! NO! NO! The neutral & grounding conductors are never bonded past the service equipment.

 

[Charles (in GA)]

Make the cable "right" and you can use it for a generator extension cord also.

Use L14-30 twist locks on each end, and if needed, make a adapter to the welder plug configuration or change the welder plug to match.

I got lucky and found two pieces of new 8/4 SOOW local from a CL seller for $100 (said it was in a van he bought from a HVAC repairman along with a bunch of other junk ). One piece, after trimming and installing ends is 37 ft the other is 45 ft. Found the ends on Ebay, $10 each shipped for new female Bryant/Hubbell ends and $25 for a lot of 4 ea individual plastic hard pack, of the male ends, Pass & Seymour. Used one of the spare male ends to make a short cheater cord to transition to my welder plug.

Charles

 

[sberry]

You can use a 12-3 if you want but 10 is ideal even for some larger machines. Since this is a home brew deal anyway why make a bunch of froggy adapters, get a cord, put a dryer on one end and welder on the other.

Can I safely just pull off the 2 hots and ground,

Not only can you but it is the way is should be done.

 

[theoldwizard1]

...get a cord, put a dryer (plug) on one end and a welder (receptacle) on the other.

+1 !