Thanks for the tip. I will use that. Is it available at home depot?
Here are the photos of the electrical panel that I just made:
It has a bunch of nice military surplus gauges and 2 120V outlets and
1 220V outlet.
I am going to connect it now and then I will be ready to give this
genset a good load test outdoors.
I may add more gauges later, the 12V voltmeter, an hourmeter, and fuel
tank level gauge.
Just gave this beast a good load test, and have some numbers from the
frequency readout. It has a 6kW/7kVa rating on the nameplate. Onan
DJE, 70 cubic inches air cooled diesel. Made in 1978 (younger than me)
4.5 kW 220V water heater element
1.5 KW electric kettle
1.5 KW electric room heater
At idle, the frequency is about 61.5 Hz.
At 4.5kw load, it is about 59 Hz.
At 7 kw load, it is about 58.5 Hz.
After it warms up, even at 7 kW, there is relatively little smoke in
exhaust. When it is warming up, there is more smoke. After it becomes
warm, the smoke goes away.
The oil pressure starts out at around 50, and after warming up, drops
to about 40, and goes even lower to about 38 or so as load increases.
The genset could hold on to the 7kW output for a few minutes.
It was not very loud, and visibly a lot of noise was coming out from
my improper muffler configuration -- a very long flexible exhaust hose
leading to the muffler, which is wrong. Muff should be close to the
I am interested in any conclusions from the frequency and oil pressure
as to whether this genset is in a good condition.
My assessment would be that those steady state frequency numbers
indicate that the governor is working pretty well, but could possibly
stand some tweaking.
You'll never get rid of short dips and peaks around the addition or
removal of large loads, but afer a second or two of settling you should
be able to get back to the target frequency. +/- a couple Hz is good for
a small generator and certainly well within the tollerance of just about
anything you'd have in a typical house. Larger generators have moch more
sophisticated governors than the mechanical ones on small sets and can
hold the freequency tighter. Those larger sets also have the benefit of
larger flywheels and more headroom on the enging capacity.
About the only thing in a typical house that would be affected by minor
frequency variations would be timers that used AC syncronus motors for
their drive, like those in typical landscape lighting transformers, and
the only affect is that they would gain or loose a little time while on
the generator. Old electric clocks would have the same effects.
What you really need is to record the instantaneous lows and highs when
large loads are added and removed. The amount of undershoot and duration
will tell you how well the engine/governor takes on the load, and the
overshoot on removal and it's duration will tell you how quickly the
If the engine was able to take and hold the full load without complaints
then I'd say it's probably in good shape. The oil pressure sounds quite
So where do I find one of these, and how much? I'd love to stick one on
the front of my 24' auto / cargo trailer. The extended shaft version
that Onan makes for bucket truck hydraulics would be nice, but I've only
seen that in gas.
Ignoramus30505, I notice that you set the No-Archive flag. That's
your right but I wanted to point this out. You're getting a lot of
helpful advice from people. Because your articles aren't being
in google, other folks in the future who might have similar problems
won't be able to search through your postings. They will see the
which may not convey enough information without the context of your
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