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control panel measurments



Original poster: "Luke" <Bluu-at-cox-dot-net> 

I recently saw a device in C Crane catalog.
It was called the Kill A Watt.  It is something you plug into the wall and 
then plug something into it.
The literature stated it could measure the volts, amps, watts and 
frequency.  It also said it could measure the power factor and VA of what 
ever was pluged into it.

This raises a couple questions.
First what technically is the difference between VA and watts?  I thought 
it was the same thing.
Or does one have to do with power factor?
Is power the apparent power (not taking the power factor into consideration 
and VA the real power or vice versa?
Or is there something else I am missing on this?


The next question is can I build a control panel that will give me these 
values for my TC?
What I would like to see on my panel is measurements of the primary side of 
my NST bank.
The values would be volts, amps, true power, apparent power and the power 
factor.
If it is a huge undertaking then I probably will not go for it just yet but 
if any of this can be obtained in a fairly simple manner I would like to 
incorporate it into the coil I am designing now.  I know voltage and amps 
is pretty easy just throw in a ct for the current and use panel mount 
meters to read the voltage to the NSTs and the output of the ct for 
current.  It is the power and power factor portion of this that has me at a 
bit of a loss.

Any one have some input for me?

Luke Galyan
<mailto:Bluu-at-cox-dot-net>Bluu-at-cox-dot-net
http://members.cox-dot-net/bluu