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Mr. Luddite[_4_]

On 10/1/2017 10:36 AM, wrote:
On Sun, 1 Oct 2017 07:10:20 -0400, "Mr. Luddite"
wrote:

On 9/30/2017 9:16 PM, 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 remember taking a course in power factor corrections intended more for
people looking to become plant or facilities engineers at large
manufacturing plants that used a lot of AC motor powered machinery.
It's quite an involved science and the "real" power available is often
not anywhere close to the "apparent" power without using big capacitors
and inductors to correct the lag/lead. Now-a-days I can't even
remember the right hand or left hand rule. :-)

===

The one I remember is the phrase "ELI the ICE man" which means that
voltage leads current in an inductive circuit, and current leads
voltage in a capacitive circuit. At one time I knew how to do the
vector calculation for degrees of lead or lag but I'd have to study up
to do that now.

Me too! :-}