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Building a rectifier

Hi,

I'm building an rectifier, I have a 45 amp power supply and I need to make it adjustable from 2 amp-45 amp. I'm using this to do some zinc plating for my tripower carbs, I sure would like some kinda dial, so I can change the amps, right now I'm using a homemade saltwater rheostat, it looks like some medieval tesla contraption , plus its kinda dangerous,,, as far as boiling over.. anyone know of any parts I can use to adjust these 45 amps ? (under 50 dollars please)

PS: my power supply has multi outputs. 5 vdc@ 45 amp 24 vdc@ 4 amp 12 v@ 8 amp it's filtered, stable and clean power.

Thanks,

Jay Conway
- Baltimore, Maryland
2003

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Sounds like your not running more than about 250 watts maximum. I suggest prowling around to find a variac that is rated for at least 250 watts (.25 KW). These are knob adjustable AC transformers and can be had pretty cheaply if you're patient enough to wait for the just the right one to appear. The variac can be installed directly ahead of your power supply. A voltage meter can connected across the variac's output and an ammeter in line with one leg of the variac's output will provide a visual indication of "what's cooking" insofar as what's going into the rectifier. The Statco website can provide hook up info. By the way; plating doesn't require any special degree of excellence when it comes to the supply, i.e. it doesn't need to be clean at all.

Good luck!

Clement Alberts
- Santa Barbara, California
2003

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Dear Mr. Clement Alberts

I do not agree with you that plating doesn't need to be clean at all.

If the ripples in the circuit are high this may definitely affect the plating.

JOY BANERJEE
- India
2003

Ripple matters a lot to some plating and very little to others. I suspect that Jay has a fixed voltage electronic power supply and that he left off the tenths of a volt. Many of these have "hammers" which will shut the unit down if the voltage goes out of a very narrow range. I have had this type units modified, but they still have limits. Mod cost was well over $50.00.

James Watts
- Navarre, Florida
2003