240V Electric Hookup Questions

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I just got a new welder and plan on running it off my generator but the plugs are not compatible. The welder has a 6-50 3-prong plug, the generator has L14-30 and 14-50, both 4-prong outlets. I assume I can just wire up a cord with a L14-30 plug and 6-50R receptacle and just drop / disregard the neutral? Does this sound right? The welder input current is less than 30 amps.

Also my 5th wheel has the standard 30A 120V plug and my generator only has regular outlets for 120V. Can I use the L14-50 generator outlet and convert to 120V 30A receptacle that uses one of the hot legs and neutral? I understand I can get an adapter to plug into a standard outlet (which I already have) but I can imagine many scenarios where 15-20A might be limiting.
 
Wait a minute. Is this a 220v welder? And does your generator put out 220-240v? If its a 120v genset, i don't see how you can make this work.

6-50 220v should need 2 legs of 110 and a ground. No neutral. 14-50 has 2 legs of 110 and a neutal.

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[Linked Image from doityourself.com]
 
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Yes on both. How big is your generator? It's possible, by doing what you're doing, to overload half the windings on the generator while the other half go unused. The gas engine can power through this. Breakers should pop, but not always.
 
Welder Power required = 26A @ 240V = 6240 Watts.

Welder Max current = 9500Watts/240V = 40 Amps, so you have about 14 Amps to spare.

If the Welder's plug isn't the same as your Generator's socket, then go to the hardware store and get a set of plugs and sockets for a short converter.

I would use three short wires of #10 stranded for the converter.
 
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If your welder is inverter based look into the quality of power your generator puts out. I think they need pure sine wave or something.
 
One really cool "tool" to make is a short adapter-extension cord with all the common 240V receptacles on it. Including each of the 2 legs of 120V with high amp connectors.

You will only be able to use 1 of the 2ea 120V legs on your 5th wheel. You can use one leg from any of the outlets.

You might also be able to use the other 120V leg and an extension cord to run (for example) your microwave.
 
Originally Posted by spasm3
Wait a minute. Is this a 220v welder? And does your generator put out 220-240v? If its a 120v genset, i don't see how you can make this work.

6-50 220v should need 2 legs of 110 and a ground. No neutral. 14-50 has 2 legs of 110 and a neutal.

[Linked Image from ambrasta.com]




[Linked Image from doityourself.com]




Sounds like his generator has 14-50 which is 240V.

Welder 6-50 is also 240V but no neutral . 6-50 is from old days where for example 240V ranges didn't have electronics requiring 120V so it has no neutral. Only 2 hots (240V) and ground.

14-50 has a neutral to get 120V. That would be the W in the above wiring diagram.

Based on the above everything he needs is there. I am just not sure if he can buy an adaptor or not ... or he should be able to make a cable with no W (neutral).

Disclaimer:
It's been a while since I worked on these kind of stuff and have forgotten and need to refresh my memory. If I get additional info or have time to research, I will update.
Meanwhile please double and triple check and do some research or talk to knowledgeable people who work on these on a daily basis. I don't want to give you a bad info.
 
just checked and they sell 14-50 to 6-50 Welder adaptor and extension cord ... or you can make your own.

Long time ago, I made something similar for a friend to connect his generator. He had a secondary breaker box and a transfer switch and needed an extension cord from his generator to the breaker box. extension cord was getting too long and I said it's not a good idea. It had to go under the garage door and loop back ... we had to drill a hole from outside close to the switch and ended up using a very short cord. 15+ years later and he hasn't complained yet so it must still be working. Granted we don't lose power that often.
 
Originally Posted by 92saturnsl2
I just got a new welder and plan on running it off my generator but the plugs are not compatible. The welder has a 6-50 3-prong plug, the generator has L14-30 and 14-50, both 4-prong outlets. I assume I can just wire up a cord with a L14-30 plug and 6-50R receptacle and just drop / disregard the neutral? Does this sound right? The welder input current is less than 30 amps.

Also my 5th wheel has the standard 30A 120V plug and my generator only has regular outlets for 120V. Can I use the L14-50 generator outlet and convert to 120V 30A receptacle that uses one of the hot legs and neutral? I understand I can get an adapter to plug into a standard outlet (which I already have) but I can imagine many scenarios where 15-20A might be limiting.


I made the exact adapter you describe for my welder. It works well.
 
Originally Posted by Donald
You should have bought a welder/generator.


Didn't want a welder/generator... Less features for more money, no way to separate the two, no thanks.
 
I wired up my extension cord that coverts a L14-30 to a NEMA 6-50R. I checked the outlet with a multimeter before I plug my equipment in and I measured:

240V between both hot legs and 120V between either hot leg and ground. Is this correct? Given the 6-50R does not use the neutral wire, I was surprised to find 120V at the ground terminal.

The manual for the generator suggests two different ways of wiring it: neutral bonded to frame (default) and floating neutral. Do I need to use the floating neutral method to utilize a 6-50R outlet, or am I okay with leaving it set up to the default (neutral bonded to frame)? Figured I better check before I fire the welder up.
 
The neutral and ground are bonded at your main panel. They are essentially redundant systems. That's why you have 120 to neutral or ground.

As for your generator's neutral, the floating neutral would be used if you are hooking it into your house. The bonded neutral is if you are using it as a stand alone.
 
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