Re: Input power measurements

To: tesla-at-pupman-dot-com
Subject: Re: Input power measurements
From: Tesla List <mod1-at-pupman-dot-com>
Date: Tue, 14 Oct 1997 21:31:38 -0600 (MDT)
Approved: mod1-at-poodle.pupman-dot-com



---------- Forwarded message ----------
Date: Tue, 14 Oct 1997 21:08:40 -0400 (EDT)
From: FutureT-at-aol-dot-com
To: tesla-at-pupman-dot-com
Subject: Re: Input power measurements  

> My mistake :(    I was looking at the voltage.  I'll redo the test and
> check the current.  Sorry for the confusion.
 
> John Freau
  >>
Thanks Jim for pointing that out.  I'm replying to my post here: 
Now that my brain has started working again (at least for the 
moment)  :)    I went ahead and observed the current waveform
on the scope.  There is some distortion, but not too extreme,
but probably enough to make the meter read wrong.  I also 
compared the phase of voltage and current, and there's an
inductive power factor of about .9 or so.  I compared the readings
of wattmeter, and voltmeter and ammeter, (for VA), and also
calculated a power factor of about .87, so there's pretty good 
agreement.  Now if I just had a hot-wire ammeter or something
similar.  I do have a small thermocouple heater unit, Weston
model 9997 i believe, that says "range uA 100".  I'm not sure
how or if this can be used.

The distortion is causing the very peak of the sine waves to be
pinched somewhat.  Also, the positive and negative half cycles
are not symmetrical, the positive one is wider.

John Freau