On Fri, 7 Oct 2011 11:32:51 -0400, "Ralph Mowery"
wrote:


"Jim Elbrecht" wrote in message
.. .
We all agree in principal. The only quibble seems to be *how* much
more some generators use while under [*how* much?] load vs. others.

My neighbor, who works on them, says [some?] Hondas are very efficient
when used at less than max load. That might be just paper theory
but if the OP cares, it is worth looking into. [Neighbor has been a
small engine mechanic for 40 years. He doesn't own or sell
generators- but in general he knows his stuff.]

Jim

The simple home generators must turn at 3600 RPM all the time to put out the
120/240 60 hz voltage. It takes so much gas to do this. Then as the load
goes up, so does the fuel usage.
Some Honda generators use inverters. This allows them to cut the speed back
under no or small loads. This will reduce the ammount of fuel used when the
load is small. When the load goes up, so does the speed of the motor.

Where the simple gasoline generators just depend on the 3600 rpm of the
engine, the ones with invertes depend on the electronics to keep the
voltage/frequency constant. The engine can run at any speed that is needed.
While I have not checked it out, it may be that the ones without the
inverters can handle large surge currrents such as starting motors beter.The
inverter will shut down,but the direct drives will try to put out the surge
current for a second or two.



Thanks-
Do you know how much difference that makes in actual use? For
instance- to use the op's numbers;
if you had a 7000W inverter type running 3500W -- vs a 3500W
non-inverter type- how much fuel would each burn?

Jim