The other issue here, w/ electric meters:
Are *they* being fooled by power factors, wave
forms, pulses, etc. etc.???
Residential kWH meters use two coils, one producing a field
proportional to voltage and another producing a field proportional
current. The fields are perpendicular to each other; one induces eddy
currents in the circular disk that spins around, and the other actually
moves the disk. It's the product of the two fields - true power - that
causes the disk to rotate. They're very fine devices, and the legal
specification requires them to be accurate to better than 0.1%.
The commercial ones that rack up charges based on power factor etc. are
more complicated.
Tim.
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