220 volt?

Discussion in 'Shop Talk' started by insanity, Jun 10, 2006.

  1. insanity

    insanity Well-Known Member

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    Hey guys i have a dumb question.Ive forgotten how to wire things since i haven't done anything like this in a good many years.And now they have an extra wire threw in there on me. :shrug:
    I need to rewire my (3wire) 220 volt welder to accept a new 4 wire plug.
    It runs fine with the black and red as hot and the green as a ground but i left the white neutral wire hanging.Will this be all right? No its not hanging literally its got a wire nutt and plenty of tape on it for now. :D
    I'm kinda stumped,scratching head trying to remember/figure it out. :help:
     
  2. Oregonsparkie

    Oregonsparkie Well-Known Member

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    The only reason I could see for the neutral is if the welder need 120VAC for controls, lights, etc...
     

  3. morrowsmowers

    morrowsmowers Well-Known Member

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    The four wire system of 240 volt is as follows: 2 wires are the power, one is neutral which is actually the ground to the motor or whatever is using the power, and then the ground wire is attached just to the metal cabinet of the device and runs directly to ground. Both the neutral and the ground end at the same points in your circuit box but it is a safety feature to seperate the cabinet ground from the line neutral.

    Ken in Glassboro, NJ
     
  4. rambler

    rambler Well-Known Member Supporter

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    I am a simple dirt farmer, not a wire wrangler. But your welder does not use any 120v at all, and that is the only thing the white wire is for. So, sealed up & left unused would be the way to go.

    Ground & neutral wires are very different, I'm a little uncomfortable with the other explination of them here.... Just because they end at the same place, does not mean they are at all similar. I know what is meant, but it seems misleading in the way it is said....

    Anyhow, 220v does not need the neutral wire, only if you had a lightbulb, timer, etc. on the welder that required it. Since you are rewiring from a 3 prong, obviously not.

    Anyhow, as this simple farmer understands it.

    --->Paul
     
  5. spam4einstein

    spam4einstein Well-Known Member

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    220 welder is 2 hots and a ground (Neutral). The other ground (neutral) is just a second ground for extra saftey. You dont need it, and many 220 items dont have a 4th wire. So wire your two hots and one ground and just forget about the 4th wire. I think standard id white(Nut.) green(Gnd.) Red and black are hot. Just make sure the N/G is at some point connected to the housing on the welder.
     
  6. rambler

    rambler Well-Known Member Supporter

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    The wire is either a neutral (white), OR a ground (bare or green).

    Never is it either as you suggest. That is dangerous. You are just confusing people. Forget about this confusion.



    Another concern, typically 4-wire plugs are for driers, which are rated at 30 amp. Many welders need 50 amp stuff. Be sure your 4-wire plug & receptical are rated for what your welder needs.

    --->Paul
     
  7. ace admirer

    ace admirer Well-Known Member Supporter

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    Modern code requires both a neutral and a grounding conductor... if you follow the neutral wire and the grounded wire back to the breaker box you will find that they do indead terminate at the same location... they are BOTH grounded or neutralized by the earth. at the appliance they may serve a different function. neutral is to return 1/2 of 220 volts back to ground (center tapp on the power companies transformer) to ensure 110 volts. the ground is a redundant path to ground should something go wrong (engerzing of appriance cabnet for example)

    giving wiring advise over the net might be considered a risky undertaking.
     
  8. insanity

    insanity Well-Known Member

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    Thanks guys, i got it.Thats what was throwing me, i thought they both ended at the same place in the box.But couldn't remember or figure how that worked.And to think i used to work maintenance at a saw mill that ran 440 and 660 volt motors.Never was trained as an electrician but new enough at one time to get by and not get killed. :D