<VV> Generator/electrical/Corvair

[Dave Keillor]

Time is usually the major factor in "un-polarization".  If the generator sits around for several months, it will gradually lose its residual magnetism.  The generator field cores are soft iron which doesn't hold magnetism very well.  

The residual magnetism is needed to get the generator "jump started".  The output of the generator is controlled by the amount of current passing through the field windings which, in turn, is controlled by the voltage regulator.  When the generator starts spinning, the field windings are not connected to the battery and the residual magnetism is used to generate enough current to pull in the field relay in the voltage regulator.

Regulators are never polarized, but the polarization is usually done at the regulator terminals -- hence the confusion.  Also, as has been mentioned, new regulators call for a polarization of the generator just to be on the safe side.  Bottom line, there is no need to polarize a generator that has been disconnected for a short time, but there is no harm, either.  A new or rebuilt unit should always be polarized.

Dave Keillor
 

-----Original Message-----
From: virtualvairs-bounces at corvair.org [mailto:virtualvairs-bounces at corvair.org] On Behalf Of Doug Mackintosh
Sent: Thursday, April 23, 2009 1:26 PM
To: Virtual Vairs
Subject: Re: <VV> Generator/electrical/Corvair

So what UNPOLARIZES the generator? I generally polarize if I install or reinstall a generator, but when do you HAVE to do it? Every time you disconnect the cables (I would think not)?