On 2/5/23 11:12, William Herrin wrote:
Hi Roy,
My guess is that your 20kw Onan isn't up to stably producing 20kw any more. Or perhaps the older transfer switch with its mechanical timer relays has gotten dodgy. The modern consumer gear is very reliable but the pre-2010s commercial/industrial gear (such as Onan) takes a lot of TLC to keep it working right.
Another thing that can happen is uneven load. The utility won't care that 80% of your draw is on one side of the circuit but that'll stop a generator in its tracks.
If you want to know for sure, get yourself an inductive clamp meter and start checking the amperages at the breakers. You can get a cheap one under 50 bucks. You just set it for AC amps, take the cover off your breaker panel and clamp the jaws around the "hot" wires coming from each breaker, one at a time.
As John mentioned, unless you have a really large house or a tankless electric water heater, it's really odd to overwhelm a 20kw generator. Even with the auxiliary resistive heat.
Agree with this assessment. 20kW rated is plenty of energy for even a demanding home. Mark.