Steve,
Thanks for the clarification.
Pat
--- In electricboats@yahoogroups.com, "Steve" <sstuller@...> wrote:
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> The Kill-A- Watt meter read 43 watts when I was using it but said the voltage was 120 volts AC, the AC current was 0.7 amps and the power factor was 0.5. The 43 watt reading was the real power as you say. Thanks. Steve S.
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> --- In electricboats@yahoogroups.com, "greenpjs04" <greenpjs@> wrote:
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> > I don't mean to pick on you today, but I don't think your interpretation of the Kill-A-Watt is correct. The meter reads real power and has already taken the power factor into account. In your example, 80 watts is going into the battery (or is being lost in the charger). The poor power factor (which is very common in switching power supplies) just means the current being drawn from the AC line is higher than that wattage would indicate. In other words, if you measure voltage and current using a multimeter and multiply them the answer will be quite a bit bigger than those 80 watts that are actually being used. ...Pat
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> > --- In electricboats@yahoogroups.com, "Steve" <sstuller@> wrote:
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> > > Fair enough. I accept defeat. If you want to try something interesting plug the charger into a Kill-A-Watt meter while charging the lithium battery. When I did this with the charger for the 801's lithium battery the apparent power was about 80 watts but there was a power factor of 50% so the battery was only getting about 40 watts. Thanks. Steve S.
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