Wire Gauge I should use?

[sni-per]

Well, I took the plunge, and bought a Hypertherm Plasma Cutter. I am now in the process of planning my wiring. I will be running about 30 feet from my service panel, an would like to install two 50 amp outlets, for my welder and cutter. Most likely won't be using them both at the same time, unless I have a helper, (my eldest daughter loves to weld, and will enjoy the heck out of the plasma cutter) occasionally.

My question is: What gauge wire would you recommend I use, with the possibility of both machines running, and what size breaker should I be installing in the panel.

Thanks in advance, for all you input. I truly appreciate all the wisdom shared on this site.

 

[rockwithjason]

you need to make up your mind if you want one circuit or two. if you have only one circuit I suggest that you put in a 50a receptacle and put matching cord caps on your machines. you will need to consult the name plates on the machines to see what they call for. assuming that they are 50a machines then you will need to run #6 wire and a
50a 2 pole breaker.

you won't be able to use both machines at the same time on the same circuit with any level of practicality and it won't be legal either. of course it's your garage and you can do as you like but if you want both machines running then you really need to have two circuits.

 

[sni-per]

That is what I was thinking too. Running 2 circuits is a possibility, and, as you suggested, would be the best way to be able to run both machines. I sort of knew that was the best route, but just needed to hear it I guess. Thanks RWJ.

 

[Mustang51js]

Yeah the reason that you can't do both on same circuit is because your limited to the 50 amps from the plug.

 

[rockwithjason]

anytime

 

[sberry]

Yes, 2 circuits normally although some of the new compacts will run 2 from one full sized circuit. One of the benefits of new machines and this class of welder is not every one needs a 6 wire. Wiring for a specific machine can save money in some cases and add a huge layer of convenience. My plasma is on a 10/50 circuit.

I looked in the manual for gigs just now, not sure I did when I iunstalled it but they allow for 10 for 208 also, the difference in cord or circuit length was 72 for 208 and could go to 89 with 230, 3 A less at higher V.
I don't even get V drop to 240 today (all the name plate math at 230) adding 12 volts again, real load is going to be closer to 30, using a 50A welder, you would need to weld a long time with a factory 50A corded machine to heat a 10 wire.
Running the v up over the years has improved transmission losses but added safety margins to wiring in some cases.

 

[theoldwizard1]

So what size is the main in your panel ?

Remember the plasma cutter needs a lot or air so your compressor will be running. Do you have enough power to run all 3 ?

 

[sberry]

In my case a larger wire on the circuit wouldn't have mattered much at 2 ft long, either way, overkill or not but also have no loss with the smaller wire and due to the fact I never run it wide open near its duty cycle, not even close.
The insulation on a modern cable is 2 x and probably then some better than when they invented the buzz box and wrote the manual for it.

 

[sberry]

Jason is correct as usual about a 50A circuit but there is a huge difference in all the real load based on what machines they are and having a daughter helping is different load than having a couple journeyman working flat rate.

There is a difference in plugging in 2 machines and needing 2 real 50A circuits.

 

[sni-per]

Thanks for all the help fellas. Ended up installing one circuit, and will be unplugging machines not in use.

 

[5mall5nail5]

I bet the price of #6/2 helped decide that eh? I did the same - I have one 50A on #6 and then two 30A on #10. I couldn't justify doing two 50A with 6/2 - too darned pricy.

 

[pattenp]

Could have used aluminum 6-6-6 SER for the 50A.

I bet the price of #6/2 helped decide that eh? I did the same - I have one 50A on #6 and then two 30A on #10. I couldn't justify doing two 50A with 6/2 - too darned pricy.

 

[5mall5nail5]

Yeah but that's huge huge and a pita. Either way.