On Sun, 08 Mar 2009 13:49:50 -0800, Winston
wrote:

Ned Simmons wrote:
The patient is a 1000W Yamaha EF1000is inverter generator. The 50cc
four cycle engine drives an alternator that powers an inverter which
outputs clean 120V 60Hz power.

(...)

Your variac is gonna be really reactive, power factor wise.
The inverter may be getting confused about the phase shift
between the voltage its supplying and the current demand
that follows.

It's not my department, but won't the PF of a transformer driving a
resisitive load be close to unity, once the xformer's start-up surge
has passed? My load is a space heater of wattage close to the
generator's rating.


Have you tried it on a purely resistive load like increasing
numbers of incandescent lights?

No, I thought of that, but haven't been ambitious enough yet to gather
all the lamps in the house that still have tungsten lamps in one
place. g The "relatively small" load I spoke of that kills the
generator is a large 310W soldering iron (not a gun). I understand the
iron will draw more current cold than hot, but haven't checked how
much more.

I'm pretty confident the motor is not performing up to spec, but
you're probably right in that I don't have a real good fix on just how
off it is.

--
Ned Simmons