Welder/Plasma supply wireing, need homework graded

[user.69169]

Don't build breakout boxes where a simple pipe to a receipt will do. Don't be scared to run another pipe if it's as practical. You don't got to get every wire in the place in 1 and nothing says quality and class like single circuit to a piece of equipment.

You typin like man who ate too many fermented strawberrys, and got his romex around his neck.

WHAT instructions you referencing, all de pages of manufacturer liability limiting printing in front of manual says nothing?

 

[workinonit]

I'm just a certified electrician but I'm confused as to what manual you are referring to. I suppose the welder manuals. NEC standards are minimum requirements. State, county and municipal codes may go beyond NEC standards but they cannot be less. As far as what I have done, it is wired to code but really it doesn't matter because it will never be inspected so I could really care less. I know it's safe.

 

[Sberry]

There is a bit of a difference. I don't figure to be smarter than all the college boys put together and minds greater than my own wrote the code. They were very careful and deliberate, this is nothing new and been in the code for decades since they invent the electric welder.
Millions of legal welder circuits been legally installed by masters with 10 cable from 50A fuses from the range side of fuse boxes and now with 50 breakers.

 

[the old grind]

We all have far more amperage of circuits in our homes than our service provides. A 50a b/o-box on a 50a circuit can have 30, 40, and 50a appliances plugged in. If any draw more than 50a the box and its circuit are ok and/as the panel should trip. At worst the power cords may be the actual fuses for each. We have crazy options to add specific breakers or fuses per tool/machine to their chords or cabinets.

My plan was to take my highest capacity access within or close 'nuf to a single outlet in each building, so on best/any bay or outside of garage or barn. I chose the old-style 3-flat 10-50 to standardize for a few reasons. Pigtails are easy to scrounge from years of dryer and stove history, as are outlets. One adapter fits all cords that came with 6-50 plugs.

I use this 6-50 to 10-50 (or not) at the end of the 20' 10-50 extension, (or not ).

View attachment 682448

btw, what I like about the 6 ga cord after using it (fat as a garden hose) is that it takes up its own slack like a coiled air-hose and coils into a ~ 24" 'stack' when not on use. I'm not about to stretch/straighten it out. Minimal 10-50 bits were on hand. Extension and adapter were < $200 and my 225a Airco buzz box, Everlast IGBT 250a MTS can run WFO anywhere the smaller stuff can. (50a plasma, etc)

My only suggestion would be to simplify outlet/Nema configs. If welders all come with 3-prong plugs I won't sweat the modern 4th wire so many other appliances/codes now embrace.

 

[Sberry]

Another thing
Because it's a minimum standard doesn't make it inadequate. In fact the same standards work so much better today given improved wire coatings and there being 20 + increase in voltage to carry the same wattage
Welder used to draw 43 back when 220 was standard now 39

 

[LouNY]

OK thats better seeing as how article 311 is medium voltage.
View attachment NEC art 630.pdf
I don't know if the attached pdf will be readable.
That has to be the most convoluted section of the NEC they have written.
Somehow welding equipment which is hard wired ( not receptacled) can have a breaker of up to 300% of ampacity of the wire in the circuit.
It has a crap load of calculations to be done including the additive other welder on the circuit,
also it has over load protection in the equipment.

So it might be possible to get under sized conductors past an inspector for your hardwired welder,
I'm glad I always considered the NEC the minimum and I will still be using at least #6 copper wire on my 50 amp receptacles.

 

[Sberry]

It only uses 4 wire if it's dual voltage. Only appliances I can think of are dryers, ranges and 50A RV. I cant think of any shop equipment. Something to consider when using old range stuff is that the recepts do not have bonded yokes.

 

[workinonit]

That section was probably put in there to cover the 4, 6 and 8 pack welders used in industrial settings. At least in part. Part of the reason is that a welder rarely if ever pulls max line current. But I agree with you Lou on sizing wire. I would never land a #10 AWG on a 50 amp breaker.

 

[Sberry]

It ain't getting it past the inspector, it's the code. No one is saying you can't wire it better but if we are asking about standards it's 2 sizes better than the machine that comes with a 12 cord needs. Skipped right past 8 to 6.

 

[Sberry]

That section was probably put in there to cover the 4, 6 and 8 pack welders used in industrial settings. At least in part. Part of the reason is that a welder rarely if ever pulls max line current. But I agree with you Lou on sizing wire. I would never land a #10 AWG on a 50 amp breaker.

It's not Just "probably" put there. It's very deliberate and "probably" in the code before they ever consider 6 and 8 packs. 10 wire is landed every day on 50 by legitimate masters. Just cause you eouldnt do it doesnt mean it isnt adequate and safe. If it wasn't they would have not had it in there the last 75 years.