According to Pop :
...
: Yes, but more slowly, right. Don't they have speed regulators
that
: somewhat depend on the load. Cars use far less at idle than
they do
: when moving the car.
:
: Actually that would be very rare. I've never seen one that
does that,
: and I've used many of them. They usually run constantly at one
of two
: speeds: 1800 rpm or 3600 rpm. That is necessary to maintain
the 60 hz

No, not so rare. MANY generators idle during periods of no-load.
Most generators around here do, including mine. If there is ANY
load though, it jumps up to speed incredibly fast.

These generators tend to be slightly upscale (as in commercial grade)
rather than the cheapos you see at HD. Usually not _big_ ones, because
they're usually used in circumstances where you're always drawing power.
The big ones often operate full time at 1800 RPM.

I recall reading about 3600-1800 or 1200 RPM idle step-downs on mid-range
commercial Onans, Generacs and Hondas. It's advertised as a feature
to make the generator last longer.

The idea being that the generator itself is much cheaper to make if
it's operated at 3600 RPM (eg: most engines produce peak power near to
3600), but the wear level is considerably increased over 1200 or 1800 -
hence the compromise of idling lower.

There's an analogous situation with electric motors. It's cheaper
to make a 3600 RPM motor than an 1800 RPM one. But most applications
need 1800 RPM rather than 3600 RPM, and the cost of gear/belt reduction
of 3600RPM is more than the cost savings of 3600 over 1800. Hence, most
motors are 1800 except with certain applications.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.