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Jacobs ladder
Posted by Mario Occhipinti on 12/10/2003, 12:38 am
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Re: Jacobs ladder
Posted by Bert Hickman on 12/10/2003, 8:35 am, in reply to "Jacobs ladder" Distribution transformers normally come configured with an internal strap that connects the center tap of the LV winding to the core and housing. Unless you have previously removed the transformer's lid and have disconnected this strap, you do NOT want to connect either the case of the transformer to ground when using your pig to drive a TC or Jacob's Ladder. If you do, one of the pig's two LV legs will be connected directly to one of the incoming 220 volt branch circuit lines (no current limiting ballast in series) while the LV side center tap is at ground (no ballast either). If you strike a HV arc, you now have no current limiting in the path of a short circuit between that 220 volt leg and ground, and you're applying a solid 120 volts to 1/2 of the pig's LV winding. This may be why you're blowing your breaker. If this is not the problem, try the following checks. Are there any other loads connected to the 50 Amp branch circuit? Is the welder a simple AC stick welder? Does the behavior change if you open up the low voltage side of the welder? If you disconnect your present setup and plug the welder into the 50 amp branch circuit does it operate normally as a welder at both the low and high current settings without blowing the breaker? Although you can get some nasty 60 Hz resonance effects between a Tesla Coil tank capacitor and the ballast that may cause excessive current draw (or "bumping") at certain current settings, this should not be a problem when using the pig to drive a simple Jacob's Ladder. Good luck, an play safely! -- Bert --
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