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badady1
Jun 13, 2008, 10:33 AM
In my Laundry room I have a 4 prong plug for my dryer. I have a 3 prong plug on my welder. They are both 220 and I have everything I need to make an extension cord in cluding wire, plug and receptacle and gang box. I know how to wire the ground but am not sure where to put the black and white wires. On the three prong plug does it matter which side they go on? There is a wider prong on one side of the receptacle. On the 4 prong plug I will be excluding the fourth prong. Does it matter which side the white and black go on? Thank you

donf
Jun 13, 2008, 11:01 AM
Badady,

What is the amperage of the dryer? What is the amperage of the welder?

By the way, there is no longer a 220 VAC. The current VACs are 120 and 240.

stanfortyman
Jun 13, 2008, 12:06 PM
I can only assume the dryer is a 30A circuit. Unless your welder can run on a 30A circuit forget it.

As Don said, there is NO "220" any more. Hasn't been for a very long time, we just can't shake the misnomer. Also, this is only HALF the equation. You also need to know the amperage of the circuit.

A typical electric dryer is a 120/240v-30a circuit. Your welder needs a straight 240v circuit hence the different 3-wire and 4-wire devices.

badady1
Jun 13, 2008, 12:06 PM
Badady,

What is the amperage of the dryer? What is the amperage of the welder?

By the way, there is no longer a 220 VAC. The current VACs are 120 and 240.
My Dryer does not have an amperage written on it, My welder is 208.

badady1
Jun 13, 2008, 12:09 PM
Sorry guys,
The Dryer is on a 30 amp circuit. The weder is a 205 max amp

stanfortyman
Jun 13, 2008, 12:10 PM
No, not the output amps, the input amps.

badady1
Jun 13, 2008, 12:14 PM
230/220 volts
47.5 Amperes

stanfortyman
Jun 15, 2008, 12:29 PM
230/220 volts
47.5 AmperesAnd you want to know if you can use this on a 30A circuit??

badady1
Jun 16, 2008, 08:59 AM
Yes

donf
Jun 16, 2008, 09:15 AM
It's an emphatic, NO!

You would need to run a #6/3 AWG on a 60 amp breaker for the welder.

KISS
Jun 16, 2008, 09:40 AM
Sorry Don, I have to disagree.

O come on. You certainly can. There will just be a limit as to what you can weld. I've connected a welder once for a temporary job. This thing was like 4' x 3' x 2'. A huge welder. Just pulled the wires out of the wall. Wirenutted it in place. The circuit was no where what was "required" for the welder. Worked fine to weld 1/4" stainless tubing.

You will not use the N terminal on the 4 wire plug. It doesn't matter which one of L1 and L2 gets connected to the other terminals. You know where ground goes.

There are terminal designations on the back with a white, black, red and bare wire connected to it. Don't use the terminal with white on it. The black and white of the welder cord go to black and red of the plug. It doesn't matter which one goes where.

As long as you realize that there will be limits as to what can be welded, everything will be fine.

So, if it's a 200 amp welder, it's now a 30/47*200 anp welder or a 127 amp welder.

stanfortyman
Jun 16, 2008, 05:12 PM
Yeah, but KISS, this is NOT smart advice to give on a public forum.
Sure it can be used, but is it right? NO. Is it safe? Maybe.

badady1
Jun 16, 2008, 06:16 PM
I wired it with a 4 prong plug. Eliminated the second ground prong. Wired it with #10 wire to a 3 prong receptacle inside of the gang box and it seems to be running the welder just fine. What's the deal? Did I just get lucky or what? It is on its own designated circuit.

KISS
Jun 16, 2008, 08:14 PM
Hopefully, you eliminated the neutral (white) and not the ground (bare).

Your welder is just smaller now because of the circuit rating. No big deal.

badady1
Jun 17, 2008, 05:45 AM
Yes. The ground to the three prong plug is wired to the ground in the four prong plug.

donf
Jun 17, 2008, 07:25 AM
Keep your fire insurance payments up. You might need it, providing that the insurance company does not choose to drop you if you have a fire.

BTW, I thought we were not allowed to give out information that we know to be unsafe.