wiring for a welder

Discussion in 'General Electronics Chat' started by Cliff987, Apr 2, 2013.

  1. Cliff987

    Thread Starter New Member

    Oct 2, 2012
    Wiring for a Welder -Or- What to do with the neutral and ground wires? -Or- What is the role of the Neutral Wire?

    My ThermalArc 211i has a fifty amp three prong plug sort of like a dryer plug. The female that fits that plug from TA bonds the ground of the plug to the metal of the box with a little strip of copper ( bonding strip).

    My wiring is Three #4 wires : Two hots & one neutral. There is also a bare ground wire that is definitely not #4, it's more like #14.

    The line driving the outlets comes from a sub panel where ground and neutral are not bonded.

    I know there is supposed to be some resistance between neutral and ground, but it's really not much as they do get bonded in the main panel. So the resistance should be a function of the run of wire more than anything else.

    I know I know: Ignore the neutral. OK.

    Do welders consume the electrons? That's not possible. It'd violate the laws of conservation of mass and thermodynamics.
    I know that in the circuits I'm familiar with the electrons don't get consumed they just do work and then move along. Which is the root of why I was thinking of using the neutral. It's BIG.

    I know this is astonishingly stupid and reflects a complete lack of thought, but bear with me:
    In my mind's eye I imagined the little electrons running back and forth as the polarity was reversed 60 times a second. I also imagined that somehow this involved the neutral wire to accomplish this which would of course mean that the current on the main hot lines would also be same on the neutral wire because the polarity has to go back and forth from somewhere to somewhere.

    Where the load is located on this circuit is, I should think, not so important, but apparently it is.
    This because the ground wires I've seen, over and over again, are very small in comparison to the wires powering the circuit; a fact that causes me some confusion.

    If the electrons do the work and move on, then they are moving on into the ground or neutral wires and shouldn't these always be as large as the main lines? But they aren't. And if the electrons are moving to the ground, which is uninsulated, why is this not an inherently dangerous condition?

    So should I be concerned with the size of the ground wire for my welder?

    I'm considering re positioning my honkin big neutralwire to the ground bus in the sub panel and using the little bare ground to cover the metal boxes. Thus eliminating the neutral entirely in the 230 circuit.
    I don't think I need a neutral since the two phases of the mains are doing all the alternating work while the neutral is not in the game at all. Never has been.
    Last edited: Apr 2, 2013
  2. BReeves


    Nov 24, 2012
    You answered your own question.. Do not use the nutral wire not needed as you have 220 between the two hots and that's all the welder needs. As far as the ground the #12 wire is big enough to blow the breaker and that is all it needs to do in case of a short from one of the hot wires to the case.
  3. Cliff987

    Thread Starter New Member

    Oct 2, 2012

    Thank you. I'm assuming the same factors apply to 230 motors as well.

    I wonder why the original line had a neutral wire. It was for a stove/oven when I replaced it with a gas stove top I re-purposed the wire to my shop.
    It's got red ,white, black insulated conductors with a bare ground.
  4. BillB3857

    Senior Member

    Feb 28, 2009
    As for why the neutral was connected the stove....... Maybe the clock/timer was running on 120VAC and needed the neutral.
  5. Brownout

    Well-Known Member

    Jan 10, 2012
    When I wired my welder, I just left the neutral unconnected.
  6. tinkerman


    Jul 22, 2012
    230 volt motors don't need a neutral. As BillB mentioned a stove would. There are the oven light, timer and outlets that require 120 volts.
  7. gerty

    AAC Fanatic!

    Aug 30, 2007

    I've run into stoves that used a neutral for one of the heater elements when the "warmer" option was selected . The oven element would run on 120v for warmer and 220v for cooking.

    Edit: as mentioned before, you don't need the neutral for welder.