Mark wrote:
"NoSpam" wrote in message
...
Mark wrote:
NoSpam wrote in message
...
Just started-up a 2.2kW dual-voltage genny after a few years of sitting
in the garage and there's no output. It's marked "Allam Generators" and
has had very little use, it was perfect when last used.
What could have happened are the connections between the exciter wiring
and
the main field coils have corroded so its not self-energising,
they are not usually the most user friendly things to dismantle though.
;(

Thanks. Presumably it just relies on residual magnetism to get started(?).
No it's a bit more complicated then that,

Do a search on Google or Wikipedia for Brushless Alternators to get a better
description of how they work.

If there aren't any "well known" failure modes I just need
to work through methodically.

Without the wiring diagram fault finding can be very difficult unless you
fully understand how they work.




Aha, that's cunning. So a small integral alternator uses residual
magnetism to "start-up" and then generate a current that's rectified and
fed to the main alternator armature. Load current is taken from the
stator and regulation is achieved by varying the current in the stator
of the small alternator. I wish I'd thought of that, it's very elegant.
I wonder why car alternators don;t work like this.

How does the regulation work, is it just that a proportion of the output
voltage is applied across the stator of the small alternator?

With this injection of knowledge it looks like it'll be a connector
problem. There's continuity from L-N at the output so presumably the
problem is in the control mechanism.

Hugh