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[email protected] gfretwell@aol.com is offline
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First recorded activity by BoatBanter: Jul 2007
Posts: 36,387
Default Propane generator science fair project

On Sat, 30 Sep 2017 21:16:30 -0400,
wrote:

On Sat, 30 Sep 2017 20:54:56 -0400,
wrote:

I dragged out Wayne's scope and a few meters to debunk a myth about
propane.
Someone was trying to tell me the output was less on propane than on
gasoline. I will admit it uses about 50% more by volume but for the
same output.
I used my convection oven for a load and that ended up being 5403
watts or around 98% of the rated output of the generator, a pretty
good test.
The wave form ended up being pretty "siney" although not perfect and
did not change with the fuel
http://gfretwell.com/propane%20project/Wave%20form.jpg
The rest of the test looked the same too.
http://gfretwell.com/propane%20project/On%20propane.jpg

I have that scope ready to go any time you want to drive to Estero
Wayne. For being 50 years old, it is still working pretty good.



===

Great, thanks. I'll be in touch via EMAIL.

It might be worthwhile to repeat that waveform analysis with a heavily
inductive load. I say that from personal experience with the 8 KW
Kohler genset on my old Bertram 33. That generator worked fine with
all loads except the Heart Interface Inverter/Charger. The charger
was heavily inductive as it approached full output and it would
severely distort the sine wave to the point that the charger would cut
back its' output, even though the load was theoretically well within
the generator's rating. Of course that resulted in a vicious circle
feeedback loop which was bad for all concerned. The inverter charger
that I have now is supposed to be power factor corrected and has never
caused any similar problem.

I am not sure what I have that fits that bill. I suppose big motors or
something may be fairly inductive. I did not notice any problems with
my PCs, TVs etc.
I did figure out the generator seems to be set up for 115/230 because
it was pretty stable at that voltage but by the time it got to the
kitchen fridge that ended up being more like 109 and it is slow
starting. I know I drop about 2.5-3v in the feeder from the generator
to the panel and that is my bad. There are probably some other losses
in the system too. I used #10/3 Romex and I would have done better to
use bigger wire. I have 50' of 6/4 SO cord that I used twice in 45
years as an extension cord for my welder. I may re purpose that, see
what else I have in the shed or I may just buy new THHN #8 or 6.
If I can just goose up the voltage a bit I doubt I will do anything.
Henc gave me a variac before he left and I might just put that on the
kitchen fridge. The one out in the tiki bar seems OK as does
everything else.