Running tombstone welder on 5KW generator

[tanglefoot]

I read the post from sparkkky recently concerning running his welder on his portable generator. It sounded like something I wanted to try. I think I might be able to change the 20 amp breaker to a 40 or 50 amp on the twist lock connection. I have some cords and pigtails I inherited from my dad after he sold his travel trailer, and I assumed these would connect to the 4-prong twist lock. When I dug them out, I found that they had only 3 prongs in a wide spacing and odd configuration. I decided to cut the connections off and make up the cord to a 4-prong twist lock. Which two conductors carry 220? Then there will be one ground. Does the fourth conductor carry another 120 volts? (If so, I'll just have to leave it off of my new cord.)

 

[midlf]

4 conductor cord has one conductor for neutral, two conductors at 120V each (voltage from one 120 to the other is 240V) and one conductor for ground. Your welder most likely has a three conductor cord. Two hots (the two 120V wires) that provide the 240V to the welder and a ground. The travel trailer cord is most likely a 30A 120V connection with the three conductors being one 120V hot, one neutral, and one ground. BTW the neutral is always white, the ground is green, and the hots can be most any other color usually black, red, blue, orange, yellow.

 

[Highbeam]

I use a 5+kw generator for my tombstone. To get from the 20 or 30 amp twistlok receptacle on the generator to the standard 50 amp receptacle I made an adapter pigtail. Don't mess with the generator's plug. Go to the home depot and buy the matching twistlok, buy 6 feet of adequately sized cording (about a dollar a foot), and then buy a female 50 amp plug to match your welder. The circuit breakers on the generator are to be left alone which will protect both sides of the twistlok.

The tricky part is that the generator has a "floating" neutral whatever that means and the ground for the generator isn't really a ground since very few people actually drive a ground rod and connect the generator to it despite the commonly supplied little ground clamp on the generator frame. Still, use the ground as though it were good.

I've tried dealing with the 4 to 3 wire problem a few ways and have never been shocked. My current setup as I recall uses only the red and black (hot and hot) and then the green ground. The white neutral wire isn't connected. I have thought about going back in there and connecting the white and the green together and using them both as the ground for the welder.

You don't need a 40 or 50 amp breaker for the tombstone. You don't want the generator overloaded. If your welding needs exceed the generator output and breakers start popping then you need a bigger generator but I doubt that will happen.

 

[George2615]

Like Highbeam said. You don't need a 40 or 50 A breaker. Changing the 20A breaker on your generator to a 40 or 50A one is the fastest way to burn out the armature in your generator. It will be better to make the adapter cord then run your welder. If the breaker trips it's doing its job to protect from an overload situation.

 

[tanglefoot]

Thanks to all. This is exactly the info. I needed.
Butch

 

[texasjohn]

Thanks guys for the wiring info generator to welder... I'll be doing this in a few days... and... WONDERFUL... happened to see this post and answer...

TBN rocks

 

[tanglefoot]

Have you lived in Jarrell very long?
Butch

 

[rdln]

according to this and my own experience it aint gonna work

http://www.lincolnelectric.com/knowledge/articles/content/ask_generators.asp

 

[mikim]

according to this and my own experience it aint gonna work

http://www.lincolnelectric.com/knowledge/articles/content/ask_generators.asp

yep -- my experience as well ... almost verbatim.....P.O.'d me cause that was one of the reasons I bought the gen ...... shoulda bought a gen/welder like TSC has for the welding portability I wanted and emer power.

 

[tanglefoot]

Thanks again. I read the Lincoln website, and the problems he describes are the same ones I already have with my portable welder, plus it weighs 350 lbs. If I had to lug a 15,000 watt generator to the pasture to weld up a brace I wouldn't be any better off than I would with the old portable.
But if I can get by with the 5,000 watt genny and my tombstone welder I think I can do what I need to do. At least, I'm going to try.
Butch