Bob Engelhardt wrote:


It's highly improbable that your machine is weaker than mine, so your
50W in versus my 200W means that mine is way too high. Unless my
Kill-a-watt is wonky.
I think it HAS to be that the Kill-a-Watt is not measuring a non-linear load
properly. If the PS was burning 150 W internally, a small fan would NOT be
able to cool the hot components effectively. Saying that 2 75 W bulbs in
the housing would not burn up is not germane. There are several components
in the PS that will be generating all the heat. Switching transistors,
diodes and maybe transformers are what will get hot. Real Kill-a-Watt
meters are SUPPOSED to properly measure non-linear loads up to some
reasonable crest factor, like 10. Probably most non-PFC corrected power
supplies won't be too much worse than a crest factor of 10 (I hope).

So, you might check this with a real electromagnetic wattmeter or a Kill-a-
Watt that is known to handle non-linear loads accurately.

Or, if you want to go nuts, get a digital scope or other scope, digitize the
current waveform and numerically integrate the true power draw.

Jon