Miller 1973 wc-20ec help needed.

Kevin64

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Any of you guys work on a navy ship welding in the early 70's? This welder calls out for a power source connection on one of the cabinets connections at 208, 230 or 460 single phase and I don't understand how to do that. It only has one connection for the power source. ONE which means to me that power has to return somewhere else. Have you ever had a return from the metal directly to the power in the shop? Have you ever heard about taking 2 115 power lines and connecting them to make 220 come out on one line? I believe someone somewhere is using a Miller WC-20E mig welder with a 20E gun and argon somewhere and can lead me in the right direction. Is it here?
 

California

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Have you ever heard about taking 2 115 power lines and connecting them to make 220 come out on one line?
Answering just a part of your question: What comes into your house is 220 volts. That is two 110 volt lines that are out of phase. 110 volts from either line to ground. 220 volts from hot to hot, no ground needed. (aside from the green safety earth ground that doesn't normally carry current).

Think of an S-wave, alternating current, that swings half above zero volts to +110, then half below zero to -110, so 220 volts difference between the two hots.

Take a voltmeter and find two breakers that show 220 volts measuring from one to the other.
 

Kevin64

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California: Ya I think I get it. The transformer on the pole in the street has a common in the middle of the windings and those windings reduce the voltage from the input line, the top of my side of the windings would be positive and the bottom would be negative so red, black and white as the middle common. I am pretty sure that I can not put the black -115 and the red +115 linked to make one 230 volt hot line. So this welder will never fire up in my shop unless I call the power company and have a single 230 power line, single phase run from the transformer. Do I got that right?
 

California

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No, the panel in your house receives 220 volts on two hots and a neutral. If you have an electric clothes dryer, stove, hot water heater, maybe central A/C, each is fed 220 volts from its own dedicated double breaker. Double because each breaker in the pair is passing its own side of the + or - 110 volts for a total of 220v sent to the appliance.

The simplest source to get 220v welder power is from a standard 30 amp electric clothes dryer outlet.
 

flyerdan

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If you don't have the wiring diagram sticker in the welder panel, here's one from an Airco 300. It's basically a rebranded Miller, so it should be the same, voltage options are the same
230vWire.jpg
If you're using existing wiring, I'd recommend pulling two butting breakers and replacing with a dedicated 220, that will be pinned so if one leg trips the other will as well.
Relocate the disturbed 110 breaker circuit to a blank spot in the panel.
 
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