breaker and fuse required for welder

[Mark @ Everlast]

Neutral is only to satisfy a 110 dedicated circuit. There is no need for a neutral. NO welder has a neutral, and for good reason. A three prong plug IS to code. A 4 prong plug actually does NOT meet code. In fact it can mess up a welder, if people try to wire an adapter and get it wrong. Could even theoretically cause you harm as well since wiring colors are different for a 3 prong welder circuit. The standard plug for any 240V single phase welder IS a NEMA 6-50. What else are you going to need to use that uses for wires in a shop? Nothing. An air compressor would only have 3. You certainly won't need a portable dryer or range.

A neutral is only used on appliances which run a separate 110V circuit, such as a stove clock, or a dryer timer circuit and allows a return path for that circuit, without tying up the ground.

 

[LD1]

A neutral is only used on appliances which run a separate 110V circuit, such as a stove clock, or a dryer timer circuit and allows a return path for that circuit, without tying up the ground.

I know alot of people with a stove in their shop. baking parts, heating bearings/races for install, garden canning were the mess of such a process is not wanted in the house, cooking a frozen pizza while working on a car, etc.

I have seen single phase 240v mills that have 120v feed motors and electronics. Same for lathes.

Maybe none of this applies to the OP. Thats fine, wanna wire a dedicated welder plug, go for it.

Someone who would mess up a 4-wire to 3-wire adapter to run a welder off a 4-prong outlet, has no business messing with electrical circuits.

 

[sandfs]

If this is the case with Cord's machine then he is seeing one leg of the transformer secondary intentionally grounded by the mfg (connected to the case) to create the separately-derived line and neutral for local 120v loads. This is very different than just connecting the neutral terminal of a 120v receptacle to a grounded surface in the hopes of creating a return path.

Yeh, let's see if I can get a snip attached here.

 

[TMGT]

If the OP is going to run conduit and using thhn then 8g is good for the 50a breaker.
I'm wiring up my shop now and the price difference was pretty good, calculated voltage drop on my runs was minimal with 8g (<3% on the longest run).
Makes it a little less expensive and easier to work with.

 

[Tractor Seabee]

Neutral is only to satisfy a 110 dedicated circuit. There is no need for a neutral. NO welder has a neutral, and for good reason. A three prong plug IS to code. A 4 prong plug actually does NOT meet code. In fact it can mess up a welder, if people try to wire an adapter and get it wrong. Could even theoretically cause you harm as well since wiring colors are different for a 3 prong welder circuit. The standard plug for any 240V single phase welder IS a NEMA 6-50. What else are you going to need to use that uses for wires in a shop? Nothing. An air compressor would only have 3. You certainly won't need a portable dryer or range.

A neutral is only used on appliances which run a separate 110V circuit, such as a stove clock, or a dryer timer circuit and allows a return path for that circuit, without tying up the ground.

Mark, when you start quoting the NEC; beware, local jurisdications often have additional and sometimes conflicting requirements, from the NEC. NEC is a Model Code, not something every jurisdictation adopts in total or w/o modifications. Electrical jurisdictation in WA state has been retained by the state as the only enforcer. As I understand it WA now requires all 120 and 240 volt receptacles have 4 conductors. If an appliance does not require a neutral then it is just not connected in the plug. Example is range and dryer outlets are required to be 4 prong.

The code here (which is violated daily) requires appliances to be connected by a licensced electrician and made code compliant. I just had a furnace replaced and though on a plug in w/a wall switch, a permit was required for changing that to hard wired and for the new thermostst wire. Yes, low voltage requires a permit and a minimum of technician licensced for low voltage. A furnace, HVAC, water heater, etc replacement requires a technician with a minimum of a maintenance electrician licensce. Otherwise they have to subcontract for an electrical contractor. Even a homeowner (not rental or commercial property) is requird to get a permit to do their own work.

Any gueses as to how often all this-rig-a-mole is ignored. Because the furnace contracor has all that paper the inspecor did not ever show up like was scheduled. They sure charged me for the permits issued in my name not theirs.

Ron

 

[Mark @ Everlast]

In a welder circuit, the hot wires are white and black, with the green as the ground. That's standard US issue with Lincoln, Miller and ESAB, and everyone else. You may argue the validity of the NEC, but if a code calls for a 4 wire plug where a three wire is used, and rated for exact use, I think insurance will have an issue with that, especially if something is UL or ETL listed.

 

[Tractor Seabee]

In a welder circuit, the hot wires are white and black, with the green as the ground. That's standard US issue with Lincoln, Miller and ESAB, and everyone else. You may argue the validity of the NEC, but if a code calls for a 4 wire plug where a three wire is used, and rated for exact use, I think insurance will have an issue with that, especially if something is UL or ETL listed.

Clarification on my previous is the 120 volt receptacles have 3 conductors, hot, neutral and ground.

Mark, it is just the receptacle that is required to have neutral and ground. I guess if your welder comes with a three wire cord you just have to change the Plug or make a cheater cord with 3 prong matching the welder and a 4 prong matching the receptacle; if the manufacturer's warranty/liability is the issue. I am not a licensced electrician but do a lot of my own work and stay up on the code as modified by the state. It kind of makes sense; in that they do want a Neutral and Ground to be combined at the appliance end as in days of old and they have no control over what is plugged into the receptacle. I remember when ranges and dryers were all 3 conductor cords even though the clock were 120V and no transformer ahead of them. Permit requirements are an electrical contractor's bread and butter.

I caveated my previous with "I understand" not that I am quoting the code. Some WA licensced electrician should clarify this as we go along. I had one inspector state "I don't care what UL or whoever the ell says you will do it our way if you want it approved. So guess what we did.

I am in the clear with my HOI if what I do is code, permited,and inspected. Only time an insurance company checks this stuff is when a casualty occurs they have to pay for; then only if that is the source of the casualty.

Ron

 

[Cord]

Maybe I am misunderstanding you. Do you mean the welder was furnished with a 120v male cord cap or that your welder branch circuit is terminated in a 120v duplex receptacle?

See if this helps to answer your question. Honestly, I don't think the outlet is any different from a 120v fan being used inside of a 220v welder and the machine not having a neutral.

 

[Mark @ Everlast]

It has been my experience that many so called expert electricians have Zero experience wiring welders and are completely unfamiliar with article 630. They tend to ignore it or act surprised and want to argue until I point them to it. The only reason for a neutral is a return path for a 110V circuit. However, most electricians who deal with industrial wiring I deal with do know about it. While the NEC may be subject to local interpretation, a whole article/section cannot be ignored.

 

[CincyFlyer]

50A is fine.

But the whole issue about neutrals...There are no neutrals in a typical welder circuit. There are only two hots and a ground.

As with my air compressor, but I ran four-conductor to the shut-off box, 'cuz I may put something else in there someday. Cheap insurance.