Using a 50 Amp welder on a 40 Amp breaker?

Greg From K/W · Thu Feb 27, 2014 11:41 pm

Will this cause any problems? I know that if I used it in a much higher range that it could over heat the circuit. I don't turn it up over 50% of its capacity and I haven't had any problems with the welds, I suppose the breakers would pop if I was over loading the circuit right? The feed from the house is on a 40 amp in the house panel. Then I put in an over sized wire out to the garage. I think it was called for 10/3 wire to feed the garage off that breaker. I put in one size bigger just to be safe. I could put a 50 amp in and not have much trouble I think. But will it damage the welder to do this?

Its an older Lincoln Tomb stone type ac welder.

roberthall · Thu Feb 27, 2014 11:56 pm

Greg From K/W wrote:Will this cause any problems? I know that if I used it in a much higher range that it could over heat the circuit. I don't turn it up over 50% of its capacity and I haven't had any problems with the welds, I suppose the breakers would pop if I was over loading the circuit right? The feed from the house is on a 40 amp in the house panel. Then I put in an over sized wire out to the garage. I think it was called for 10/3 wire to feed the garage off that breaker. I put in one size bigger just to be safe. I could put a 50 amp in and not have much trouble I think. But will it damage the welder to do this?

Its an older Lincoln Tomb stone type ac welder.

You will be fine. You're welder doesn't run at 110 volts.

Superiorwelding · Thu Feb 27, 2014 11:59 pm

Greg,
From what I have come to understand, the 50A from your welder is at its "rated output" which in this case is 225 amps. If you stay away from the upper amps you will be fine. It will not damage your machine.
-Jonathan

Arizona SA200 · Fri Feb 28, 2014 2:00 am

If i recall correctly 50a requires 10 ga for a certain footage, you can look up these calculations online. If you stepped up the wire ga and have a 40 a breaker running it the worst that could happen is trip that breaker. I say run it wide open and see if it trips and if it does back it down a bit and try again. Try to find the max of what it will allow.

Tombstone · Fri Feb 28, 2014 5:14 pm

You're all good. 99% of the time you'll probably never go over 135 amps on that buzz box for 1/8" electrodes. Most 6010/6011's run at around 90 amps, 6013's and 7018's at around 120 and 7014's at 120-135.

With the above in mind, I doubt you'll ever need to draw the full 50A of that machine's capability.

Fri Feb 28, 2014 8:08 pm

Arizona SA200 wrote:If i recall correctly 50a requires 10 ga for a certain footage, you can look up these calculations online. If you stepped up the wire ga and have a 40 a breaker running it the worst that could happen is trip that breaker. I say run it wide open and see if it trips and if it does back it down a bit and try again. Try to find the max of what it will allow.

+1

If you've oversized the wire, the breaker will trip ONLY if you overload it. You should not ever likely trip that breaker using a 1/8" rod, where you'll never be above 70% of that ol' tombstone's capacity.

Steve S

Greg From K/W · Fri Feb 28, 2014 11:40 pm

OK thanks guys. I thought that was the case. I appreciate the input.

Bulldog2010 · Sat Mar 01, 2014 1:37 am

It all good how u got it set up. As the wire to the breacker a 50a needs to be 8/2 or 6/2 a 40a can be run with a 10/2 or you can step up to a bigger wire. I think you will be fine the way you are.

Greg From K/W · Sat Mar 01, 2014 12:07 pm

I think I ran 8/3 wire out there. So I am safe. I put the same plug on my big compressor. Running that on the same plug when I need it. Yee haw I am rocking in the shop now LOL! Just if it wasn't -20 out there LOL.

Braehill · Sat Mar 01, 2014 12:51 pm

To the -20*, as my friends would say, "The heat's in the tools".

I'm sure you will be fine just because that particular model welder has probably in it's 70+ year history has been run on some very questionable wiring and has endured. I know it did at my house while growing up. When I would strike an arc in the basement (I know it's not recommended, it was the 60's) the lights would dim in the rest of the house. Then it was used in the small garage that my dad built about 100 ft. from the house and a piece of 8/3 was used to power the whole garage.

The funny part was if you blew a fuse in the house you left yourself in the dark in the garage and had to fight through whatever you were working on to get out and go replace the fuse.

Len

Arizona SA200 · Sun Mar 02, 2014 5:26 pm

Otto Nobedder wrote:
Arizona SA200 wrote:If i recall correctly 50a requires 10 ga for a certain footage, you can look up these calculations online. If you stepped up the wire ga and have a 40 a breaker running it the worst that could happen is trip that breaker. I say run it wide open and see if it trips and if it does back it down a bit and try again. Try to find the max of what it will allow.
+1

If you've oversized the wire, the breaker will trip ONLY if you overload it. You should not ever likely trip that breaker using a 1/8" rod, where you'll never be above 70% of that ol' tombstone's capacity.

Steve S

I guess the point i was getting at was the breaker trip before the wire can get hot causing a fire. I do agree that 1/8 won't ever pop that breaker but i like to know what the limitations are.