3000W Chinese Gensets Info.

dash8wrench wrote:
Interesting info there professor. Are you speaking of the core of the electrical generating plant or the core (rotating and reciprocating components) of the engine itself?

The core of the electrical generating plant.

Let's take alook at the temperature issue a moment:

While I am not positive, I strongly feel like the insulation used in the windings of the generator(s) is FORMVAR. This insulation material is rated for temperatures up to 105 degrees C or 221 degrees F. You can look at specs for the insulation here .

All of the plastic jacketed wire in the generator and front panel appears to be THHN, which is a heat resistant thermoplastic rated for a maximum temperature of 90 degrees C or 194 degrees F.

Both the stator and rotor of the generator (actually, it’s an alternator) need to be kept within these temperature ranges to assure longevity as the insulation will begin to break down at excessive temperatures and eventually fail.

As current demand increases in the generator so does the temperature due to the resistance of the wiring used. There are two other factors that also increase temperature we have never discussed – eddy currents and hystersis.

Anyway, awhile back I made some temperature measurements of the generator (NOT the engine) using a non-contact infrared thermometer as a prelude to building an enclosure for sound abatement. As expected, as current demands increased to a value approaching the maximum rated run current, the temperature of the generator began to rise dramatically.

Now, my recommendation to reduce the continuous run rating by at least 200 watts for each 5 degree rise in temperature above an ambient of 85 degrees F is more of a “seat of the pants” advisory rather than a scientific, exact calculation. I did do a little math with BTUs, watts and temperature at the time, but I did not write it down – thus, I would have to repeat the tests to give you exact numbers.

The bottom line is that if the outside temperature is 100 degrees F you should limit your load accordingly. For example, if the continuous run current is rated at 2,800 watts ( 23 amps) it would be wise to reduce your maximum run current by at least 600 watts to 2200 watts or 18 amps. BTW, this load is within the limits imposed by a single RV air conditioner. I also believe that these considerations should be applied to any brand of generator as a precaution to avoid an early demise of the generator (not the engine).