What gauge to wire a 50 amp line?

[jtybt]

I have a 20 amp 220 for my small welders but decided I might as well run a 50 amp along side. It's just a 25' run from the service box. I have plenty of 12/2 romex around but wasn't sure what would be appropriate for a 50 amp line.

TIA


P.S.
I now have a 225LX and waiting for a PP50

[Ray]

Technically 12 Ga. will handle 50 amps, but I would go with at least 10Ga.
Here’s a link to calculate minimum conductor sizing.
http://www.elec-toolbox.com/calculators/voltdrop.htm

[rinktumbody]

I have a 20 amp 220 for my small welders but decided I might as well run a 50 amp along side. It's just a 25' run from the service box. I have plenty of 12/2 romex around but wasn't sure what would be appropriate for a 50 amp line.

TIA


P.S.
I now have a 225LX and waiting for a PP50

At Home Depot today I bought 4-conductor 10 gauge, recommended by the salesperson. It was about $2.00 per foot.

[jtybt]

$2.00 a ft! OUCH.

To complicate matters, I have a 10 Ga 25' extension cord putting total run at 50' so I presume 10 Ga Romex is much better.

What is the fourth wire for? Ground? I have a Leviton 50 amp dryer plug with no ground.

[Steveg]

You should run 6 ga. wire for a 50 amp circuit.

sg

[performance]

I agree, especially any distance from the panel box.

[jtybt]

What would be the amp draw of the 225LX or the PP50...not being used at the same time.

The calculator link said 10 ga up to 50'. I measured the actual run, 24'.

Electrician at HD said the line and breaker should be matched to the unit being used.

Actually sounds to me that it's OK to used larger gauge wire as well as plugs and receptacles as long as the breaker matches the 'appliance' being used?????

[performance]

Both show a max of 39 amps

[jtybt]

OK Thanks.

I've been running the 225LX off my 220/12-2 20 amp breaker with no problem so upgrading to 10-2 40 amp should be OK! Very few of my actual welding is done over 125 amps and 2 minutes.

[rinktumbody]

$2.00 a ft! OUCH.

To complicate matters, I have a 10 Ga 25' extension cord putting total run at 50' so I presume 10 Ga Romex is much better.

What is the fourth wire for? Ground? I have a Leviton 50 amp dryer plug with no ground.

One wire is ground (green), one is white (neutral), one is red (hot) and the other is black (hot). Good luck!

[performance]

You could wire color for color and trim the red wire or other color wire, whatever color it may be. Just be sure to hook up the green ground wire to the middle round post. The 4th wire is considered a safety ground. If you will observe in some true NEMA welder type plug connections, there are actual wire colors printed on the plug itself, showing you what color to use. They all say black and white for the two hot legs and green for ground. I would not use the red if this is an extension type plug, just use the colors that are used in the welder if it terminates into a male plug and not directly into the panel box.

[Steveg]

I don't want to be a spoiler, but, take a look at the IEC you will see the max fuse size for #10 non metallic sheathed cable the kind sold at HD is 30 AMPS.

sg

[jtybt]

Turns out I already had 10/2 with a 20 amp breaker. Upgraded to 40 amp breaker and 50 amp plugs/receptacles.

[shawn]

i really hope your not saying your gonna try and run 40 amps through 10 ga wire. if so i hope you have a good house insurance policy. for a 40 amp breaker you should be running atleast #8 and for a 50 you should be running a #6 otherwise you will be getting that wire red hot when pulling a max load and too many hot cold cycles will make the insulation melt off and crack and eventually creating a short in the walls or whereever the wires run which will in turn eventually burn your house down.

i've been an electrician for 17 years now and have seen people do this waay too many times for my own comfort and wonder why heir house burnt down or why their equipment burns up. the problem with running a smaller gauge wire for a larger circuit is it won't flow as well as the larger wire which in turn causes more resistance. the resistance in the wire makes the welder work harder to accomplish the same thing because it's not getting what it needs to do the job.

picture a 2" water line being used to fill a swimming pool now put a section of 1/2" at the end of that 2" line. your basically doing that same thing by using a wire that's too small for the load. your connection at the breaker are gonna heat up, the wire itself is gonna heat up, and your welder is gonna heat up because of all the effort it's putting into trying to get what it needs. somewhere something is gonna fail. most of the time it's the it's the appliance trying to be used but the other times it's either the wire or the breaker and either 1 of those are very adept at starting a fire

[shawn]

oh and by the way read the sentence at the top of the page of that link. he tells you his calculations aren't up to code and to reference the nec to make sure he's right

[jtybt]

What would be the amp draw of the 225 with a base amp setting of 125 amps?

Most of my base settings are between 55 and 90 amps welding .060" or thinner SS with foot peddle.

Even welding thick aluminum set at 127 amps with a 20 amp breaker, I didn't pop the breaker. That's the main reason I'd like to know what the actual amp draw is at different base settings. I figure there's a formula somewhere.

[shawn]

look at the nameplate on the unit that'll tell you what the max draw is on the unit. just because it's a cut 50 doesn't mean it'll pull 50 amps from your panel.

[Rodsmachineshop]

yes dosnt pay to cut corners and not use the wire size you should use . My machine shop is wired in number 6 wire when setting up my machine shop ended up using about 3 x 500 ft rolls of number 6 , most my machine are 3 phase so you end up with a extra wire to run . plus all the emt conduite and breakers and sub boxs. I think with everthing doing it with my dad was like 1500.00 . but know i am up to code and not over stressing the wiring.

[jtybt]

OK, so I pulled the 40 amp breaker and will go to a 30 amp breaker with 10AWG.

At least that way it will pop before things get hot. I might even go back to 20 amp breaker. It was working fine with the 20 amp breaker. Mainly I wanted to go from a 20 amp plug to a 50 amp plug cuz that's what I've found at most shops/yards that I might have some work.

[Ray]

Sorry I steped out. If Shawn is an electrician I'd beleve him over anybody including me.
Here's another link , this one also acounts for stranded wire.
If you go buy this calculator 8GA solid core will carry 44.6 amps over 25', personaly I go for overkill I ran 4GA across the shop for a 50amp circut for my compressor, it does seem funny the 250EX would have a 12GA cord on it though.

http://www.geocities.com/CapeCanaveral/Lab/9643/awg.htm