Folks
I got this excellent power measurement primer from Yokogawa Electric
(Yokogawa Corporation of America [YCA] for us in the 'States).
http://www.yokogawa.com/tm/tr/tm-tr0605_06.htm
I use Yokogawa WT20xx, PZ4000, and WT3000 powermeters/analyzers
at work and they are the "top of the metrology pyramid" for AC power
measurement capability. They are used pretty exclusively by power
utilities for substation/feeder loading surveys, large load power
monitoring, motor / transformer efficiency measurement, etc.
I have been to their SOTA Tier 2 Calibration facility
in GA (Atlanta Region). Their equipment is pricey (WT2010 single phase
wattmeter is 10k, 2030 or 3000 is 20k + options), but excellent deals can
occasionally be had on surplus market. Alex Tajnsek picked up a
serviceable "second generation" WT2533 (predecessor to WT20xx series)
DSP wattmeter for $20 US (no joke) at the Richmond salvage yard in
a box buried under some tech manuals and miscellaneous parts.
Yep, fully functional, and even had a still valid cal sticker on it... :^D
So guess what we are going to use to measure power on his TC's???
Best Regards
Dave Sharpe, TCBOR/HEAS
Chesterfield, VA. USA