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Re: Question of polarity.

To: z510z@yahoo.com
Subject: Re: Question of polarity.
From: "Donald H. Locker" <dhl@mrdog.msl.com>
Date: Thu, 24 Jun 1999 09:53:43 -0400
You probably also have to polarize the generator.  (DO NOT DO THIS TO
AN ALTERNATOR!) before starting the car, force some current to flow
through the field winding in the "correct" direction.  Using some
handy piece of insulated wire, preferably fairly large gauge, connect
one end to the positive side of the battery and briefly touch the
other end to the ``F'' terminal on the generator.  You should get a
healthy spark and the generator should begin delivering current.
(Check the output voltage on the ``D'' terminal.)

The problem is that the field poles retain some residual magnetism
oriented _opposite_ to that required to generate in a negative ground
environment.  As long as the polarity is wrong, the output will be low
and of the wrong polarity. (IIRC)

Good Luck.
Donald.

> Okay, here is my weird quandry for the week:
> 
> I've got my 70 mk III currently running negative
> ground.  According to the books, this is how the
> machine is normally supposed to be set up.  However,
> up to this year we'd been running positive ground on
> the car.  Intelligently, we switched it over to
> negative right before we got it running for the year. 
> Nowwe've been having problems keeping it charged.  One
> of it's DPO's decided to put the 1148 engine in
> instead of the 1296, and apparently it's quite the
> early mk I engine.  
> Logic tells me that I should reverse the battery back
> and everything should be fine, right?   Tell me I'm
> not entirely crazy.  
> 
> Thanks a bunch,
> 
> Zach Zaletel
> 70 Spit Mk III
> http://freespeech.org/zach
> 
> 
> 

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