Yes true, but those will be running during the tests so its the aggregate that I am looking for. I thought about looking at the power factor as well but truth be told, the electric company only cares about apparent power, the don’t care about real power. Im doing this for a costing exercise to determine the true cost of running the unit.
At least my power company only cares about real power. kVA metering is not a thing around here, although I agree it’s better.
And to discourage abusing that we also have a separate power factor penalty, but it’s a simple calculation of IF PF<0.97 THEN (.97-PF)*(kW Demand Bill) for customers with demand meters, anyone without a demand meter (residential customers and small commercial) do not get power factor penalties.
Correct! That is why I abandoned that approach. I’m a bit old school so we call it Imaginary power, but the modern vernacular is Apparent Power. I wouldn’t imagine it would be too far off kilter, as there is a lot if resistive load and the whole thing is run off a switching power supply anyway, even the heaters. So for me, my biggest concern is RFI with all my radio stuff 
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Haha real power is orthogonal to reactive power, yea imaginary is better though. Even better is the obligatory “watts is the beer, the foam is the vars, and the whole glass is VA”
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Hahahaha Like that one!
We have a scada system to monitor PF in real time. For short hand we generally just use kva as kv because its close enough and we shouldn’t be designing anything to fall into the difference
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Oh no… That’s horrible
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Heh oops I meant KW, not KV. Yeah it would not be good to use power in place of voltage lol
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So here’s what I came up with on my little experiment last night. I made a box and inserted a current probe from a power monitor meter i had laying around. One of those multifunction panel meters that shows line voltage, Freq, PF, Current and Wattage. I monitored the meter through the cycles and recorded the readings (see below). BTW power factor was near unity most of the time, .98-.99. At times it dipped to about .96 but I do not know how accurate this cheesy little meter is.
THE SETUP:
THE RESULTS:
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Here are some numbers from another thread:
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