Trace/Frig. [RE-wrenches]

[Sharkey]

> Maybe it's time for Wrenches to try selling their 
>customers sine wave models.

	List;

	I think that Richard's probably right here. Modified sine wave inverters
are great for certian applications, but running ANY TYPE of induction motor
is not one of them. Induction motors have terrible power factors, being
very inductive (duh). Some inverters correct for this with "power factor
correction" (Heart uses an internal function called 'off-time'shorting',
which actually uses the built-up magnetic field inside the motor to give
the motor itself a little boost). Universal motors (ones with brushes) seem
to do pretty well, but variable-speed tools and such have an annoying
delay, even when the inverter is awake and operating, waiting until the
speed request is high enough to fire the SCR and start the tool (at what
will probably be a too-fast rate). I've never had any computer or audio
equipemnt problems, but of course, we all know they exist.
	Kurt, I mentioned the SCR controller beacuse I thought that maybe a newer
fridge might have a solid-state controller instead of a relay, etc. If the
inverter is awake when the fridge starts and you're still getting growling,
stalled motor noises from the compressor, I'd suggest trying a different
inverter. A sine-wave would be the best choice, although you may find a
mod-sine of a different model/manufacturer to work better than the present
one.
	Good luck

	-S
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