Jim Michaels wrote:
On Fri, 26 Jan 2007 20:34:42 +0100, Thomas Prufer
wrote:

On Fri, 26 Jan 2007 09:47:44 +0000, NoSpam wrote:

Thanks. Presumably it just relies on residual magnetism to get
started(?). If there aren't any "well known" failure modes I just need
to work through methodically.
Some generators may fail with a "no residual magnetism left" mode -- mine has
something like that in the manual. The curse, ISTR, is to attach a 12 volt DC
source to the output and then start up the generator again.

I've googled a bit and found this:

http://www.engineersedge.com/motors/...d_flashing.htm

(wot basically says "read the applicable manual...)

and this bit of magic:

http://www.perr.com/tip16.html

This method seems to have some flaws.

It certainly will not work with a variable speed drill

It appears to state that drills have permanent magnets (Ac powered
drills don't)


Correct.

It assumes that a drill will generate some power when spun by hand,
this would be a very small amount of power.


That is also correct. Most motors with field coils will ultimately spin
up and start to generate due to residual magnetism.