Quote:
Originally posted by bigben2k
I thought those were startup caps, to prevent a large power draw, when you turn it on?
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Their use is twofold, yes they help reduce peak current during startup, but they also help smooth out the inductive loading.
Quote:
Originally posted by bigben2k
Wouldn't a meter compensate for the inductive load? I mean, if it measures current, and the current is cyclic (i.e. AC), then shouldn't it still give off a good reading?
From what I remember in electronics courses, P=VI, but in AC circuits, you have to use the RMS values: 127 Vac, is actually rms, aka averaged, as the peak is somewhere around 170 volts. RMS is the actual average value over the sine wave in the AC signal.
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No a RMS AC meter will only be accurate with a pure sine wave. The more inductive the load the more it will be off. ie the wave form looks less and less like a sine wave.
Quote:
Originally posted by bigben2k
I don't see the numbers being off by too much: if the pump was almost completely obstructed, you should get the max power rating of 45 Watts, no?
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Look at Since87's numbers. Unrestricted measured about 35W but the V x A = 98W. BIG difference.
Since87 some help explaining this, please?