Wiring for welder

[vbtj]

I searched and didn't exactly find the answer. I am looking at a Hobart 180. I was wondering does anyone know if this would be safe to run off the dryer plug it has a 30 amp breaker. My other option is their used to be a hottub at my house and their is a 50 amp breaker not being used anymore and I could also use the wire black, red, white and solid copper wire looks like. The wire is also pretty good size. Any comments thanks

[Travis Waldher]

http://www.hobartwelders.com/om/0900/o925b_hob.pdf

Your 30A drier plug would be perfect

[Mechanos]

That welder will run fine on a 20A circuit, but will be quite close to the capacity of the breaker. I have a Miller 175 (basically the same thing) but I run it off of a 30A breaker just to eliminate the possibility of neusance tripping. It's not a problem doing this since the welder itself has internal thermal overload protection. You will be fine using either your drier plug or the 50A circuit you spoke of.... whichever is more convenient for you.

[Travis Waldher]

The 50A is a poor choice.

While the welder will work, if anything goes wrong the welder might before the breaker trips.

[vbtj]

Thanks guys I guess I will use the dryer plug. What about making a 20-30 ft. extension cord for it. What size wire in the cord?

[jasonmt]

Originally Posted by Mechanos

That welder will run fine on a 20A circuit, but will be quite close to the capacity of the breaker. I have a Miller 175 (basically the same thing) but I run it off of a 30A breaker just to eliminate the possibility of neusance tripping. It's not a problem doing this since the welder itself has internal thermal overload protection. You will be fine using either your drier plug or the 50A circuit you spoke of.... whichever is more convenient for you.

A 50A breaker with a Miller 175 or a Hobart 180 does not meet the requirements of the NEC article 630 as the rated primary current is 20A.

In light of this I would caution vbtj to take whatever "advise" he receives from this post with some caution and not to rely upon its veracity until he has contacted the local AHJ (Electrical Inspector).

NEC article 630:

"Welders
Arc Welders must be protected by a fuse rated at not more than
200% of the rated primary current. The fuse protecting the supply
conductor can serve as the welder protection, if the fuse is rated at
not more than 200% of I1max or the welder rated primary current
[630.12(A)]."

[Travis Waldher]

Originally Posted by jasonmt

A 50A breaker with a Miller 175 or a Hobart 180 does not meet the requirements of the NEC article 630 as the rated primary current is 20A.

In light of this I would caution vbtj to take whatever "advise" he receives from this post with some caution and not to rely upon its veracity until he has contacted the local AHJ (Electrical Inspector).

NEC article 630:

"Welders
Arc Welders must be protected by a fuse rated at not more than
200% of the rated primary current. The fuse protecting the supply
conductor can serve as the welder protection, if the fuse is rated at
not more than 200% of I1max or the welder rated primary current
[630.12(A)]."

Hey now... I gave good advice.

As for his extension cord - personally I'de go with 6/4 SJOOW or SOOOW. WAY overkill for a 30A circuit, but if he wants to use it with a larger device/circuit later he could.

Otherwise 8/4 would be my next choice. If I were to go with 10/3 I would have to take a close look at how long the circuit already is to make sure I don't have excessive voltage drop. NEC maximum drop is 5%.

[Aces'n'8s]

Usually, voltage drop isn't "that" much of a consideration on runs < 300' . But...if you live in a mansion or a large multilevel home...I guess you should check the length.

Like it was stated earlier, it is NEVER a good idea to install a higer capacity rated protection device i.e. fuse or breaker to avoid possible "nuisance overloading." Doing this will likely create more problems and potential disasters than if you had just left it alone and reset the original 20A rated circuit when the breaker tripped.

[Travis Waldher]

Originally Posted by Aces'n'8s

Usually, voltage drop isn't "that" much of a consideration on runs < 300' . But...if you live in a mansion or a large multilevel home...I guess you should check the length.

Well, if a 30A device is used on a 30A circuit, with 10GA wiring, the max run you could have before exceeding 5% voltage drop is about 168 feet.

given that most people just think that a 30A device can be plugged in to a 30A circuit, I advise on the side of overkill.

[vbtj]

It's only about 50 ft. from the dryer to the breaker box. If I make a 20-30 ft. extension cord off the dryer plug in to welder then I should be o.k. right.

[Kendo]

10/3 will handle up to 30 amps no problem and for your 20-30 foot run it won't be an issue.

BTW, your dryer plug has an "extra" wire in there - neutral. That's because the power is split inside the dryer to run (2) 110V devices - motor for the drum and heater coil. You do not need the neutral for your welder, only the 2 hots and ground.

I run my MM210 on a 30 amp breaker, so unless you're cranked all the way up to max and welding close to the duty cycle, a 20 amp breaker is more than enough. You may want to consider replacing the unused 50 amp with a 20 and running off that. At least you'd have the protection of the rated breaker for the device.

And I would run 10/3 on a 20 amp circuit. Oversizing your wire is just good common sense. I'd rather pop a breaker than overheat a wire.

[GA_ZUKI]

Originally Posted by Kendo

10/3 will handle up to 30 amps no problem and for your 20-30 foot run it won't be an issue.

BTW, your dryer plug has an "extra" wire in there - neutral. That's because the power is split inside the dryer to run (2) 110V devices - motor for the drum and heater coil. You do not need the neutral for your welder, only the 2 hots and ground.

I run my MM210 on a 30 amp breaker, so unless you're cranked all the way up to max and welding close to the duty cycle, a 20 amp breaker is more than enough. You may want to consider replacing the unused 50 amp with a 20 and running off that. At least you'd have the protection of the rated breaker for the device.

And I would run 10/3 on a 20 amp circuit. Oversizing your wire is just good common sense. I'd rather pop a breaker than overheat a wire.

all good info here.

glade you asked before doing



i have a lincoln SP-175T 220v 20amp with the cart and a micro cut plasma cutter 16amp 220v. what i have at the present is a 12ga drop cord cut down to 45ft with the 220v plugs on both ends for the plasma cutter and 2 20ft 8ga sj cord with 50amp ends for the welder. the welder came with a 50amp plug so i just matched it.

the reason for both cords is i had a lincoln 110 weld pack 110v. so when i upgraded i used what i had. what i'm gonna do is in the future. up the amps to 30 on the sj cord and add a small breaker box at the welder cart. mostly so i can do away with so many cords on the floor. because i have a cord for the plasma cutter, welder, and air compressor which when needed i run a chop saw.i never run all at one time except the plasma cutter and air compressor.

[nissancrawler]

I run 25' of 10/3 on my hh 175. The garage wiring is 6/3. The breaker is 30 amp. I've never tripped the breaker, or felt the cord get warm.

[glfredrick]

When I made my extension cord for my welder, I piggybacked a 110 box on the back of the welder plug box so I have 110 available at the welding cart as well. Just pull power off of one leg of the 220 circut plus the neutral.

[Mechanos]

Originally Posted by glfredrick

When I made my extension cord for my welder, I piggybacked a 110 box on the back of the welder plug box so I have 110 available at the welding cart as well. Just pull power off of one leg of the 220 circut plus the neutral.

Technically, that would require you to use a 4-conductor cable: two hot legs, neutral and a ground. Yes, it can be done with a 3-conductor cable, but it's not right... you'd be using the 240V circuit's grounding conductor as the grounded conductor in the 120V circuit which would also leave the 120V circuit without a grounding conductor. Also, if this circuit were fed by a subpanel with isolated grounds & neutrals, it would bring a whole new level of wrong into play.

[vbtj]

Welders on it's way Hobart 180. Can I run 10/3 from the breaker box say 60 feet through my attic to garage. Change out the unused 50 amp breaker for a 20 amp breaker or 30. Also make a 20 ft. cord out of 10/3? Opinions?

[Mechanos]

Originally Posted by vbtj

Welders on it's way Hobart 180. Can I run 10/3 from the breaker box say 60 feet through my attic to garage. Change out the unused 50 amp breaker for a 20 amp breaker or 30. Also make a 20 ft. cord out of 10/3? Opinions?

Yes, yes, and yes. I would go with the 30A breaker.

[u2slow]

Originally Posted by vbtj

Welders on it's way Hobart 180. Can I run 10/3 from the breaker box say 60 feet through my attic to garage. Change out the unused 50 amp breaker for a 20 amp breaker or 30. Also make a 20 ft. cord out of 10/3? Opinions?

Use Romex, BX, etc across your attic, but use proper flexible cord (often called 'cabtire') for the 20' cord.

Probably best to use the recommended 25A breaker
http://www.hobartwelders.com/om/0900/o925b_hob.pdf

[vbtj]

I dug up the old hot tub wire today. It is 8/3 is this o.k. for the welder and to run through my attic.

[u2slow]

Originally Posted by vbtj

I dug up the old hot tub wire today. It is 8/3 is this o.k. for the welder and to run through my attic.

#8 is great. Is that 3 insulated (red,black,white) plus 1 bare?

If so, you may even want to consider a small subpanel.

[vbtj]

Yes it is three insulated and one bare. Please explain

[u2slow]

Put the #8 on a 2-pole 40A breaker in the main panel. Find a small 6-12 space panel to put on the other end of the #8 (in your shop, garage, etc).

In the sub you put in a 2-pole 25A for the welder circuit. Run a short branch circuit (3-4'?) to a welder receptacle. Now you can add to the sub for future loads.

40A goes a long way in a smallish 1-man shop. I run my welder, compressor, lighting, and bench plugs without issue.

[vbtj]

Thanks man may look into that in the future. On tight budget right now that is why I spent an hour yesterday digging this wire up. Use what I got and don't spend anymore than I have to.

[vbtj]

Ran the 8/3 yesterday and got my 30 amp breaker and receptacle today and finished the wiring. Man it is a big difference between the 180 and the old 110 volt 135. Needless to say I will never go back. Thanks for the advice also.