746 watts per HP is a theoretical number assuming 100% efficiency which isn't the case. Actual power consumption is somewhat higher. In May 2001 I measured the current for my 1 HP 1997 vintage Hayward superpump and it was about 7.5A measured with a clamp-on ammeter, relates to 1800W. Don't know what the power factor correction is which would reduce the actual power somewhat. That was at a filter pressure of 15 psi, least flow restriction. If you really want to measure the power for the pump, the best way is to use the watt-hour meter for the house. I'd have to refresh my memory but you can count the revs of the disc in the meter and the meter has a calibration in watt-hours per rev or something like that. I forget how the specs are stated.
Al
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