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Re: Positive ground alternator?

To: Paul <9laser3@bright.net>
Subject: Re: Positive ground alternator?
From: Simon Favre <simon@mondes.com>
Date: Wed, 02 May 2001 16:22:32 -0700
Are you sure it's an alternator? 1964 sounds like it should be a generator.
If you know some basic electronics, and have the right schematics, you can
use a negative ground generator to produce positive ground current, and 
vice versa. A generator doesn't know the difference. In the usual generator
circuit, it's the generator light that "polarizes" the generator. Anything
else is hocus pocus. The regulator and the generator are usually matched to
each others max ratings, so mixing and matching brands there can be 
dangerous. I used to have a Lucas generator (positive ground) happily 
putting out negative ground in an Alfa Spider that also didn't care which
polarity it was fed.

Alternators are polarized by the way the diode chassis is mounted, and they
are all negative ground, AFAIK. There is no easy way to change the polarity
of an alternator.

Simon

Paul wrote:
> 
>   I'm looking to replace a positive ground alternator in a 1964 Datsun 1500.
> Since Datsun never brought too many of these little cars in to the states,
> finding parts is rough.  Does anybody know of another car that was imported
> that used a positive ground alternator?  I seem to remember burning up one
> in a 1970 Ford Cortina by wiring it backwards to the battery.   Were they
> positive ground or is my memory finally gone too!
> 
> Paul
> Ohio Roadster Owners Club
> Sloan Racing

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