[Amps] Freescale LDMOS devices

David Kirkby david.kirkby at onetel.net
Tue Mar 12 07:13:21 EDT 2013


On 9 March 2013 04:34, jeff millar <wa1hco at wa1hco.net> wrote:

> Power meters measure RMS current and RMS voltage. But Watts RMS only equal V
> rms x I rms when the power factor is 1.  For lower power factors you pay for
> Vrms x I rms which is greater than Wrms.

> jeff, wa1hco

RMS power is not a useful quantity. Whilst it is possible to compute
the RMS value of power if you want to do the maths, it is of no
practical significance in any application whatsoever. Whilst RMS
voltage, RMS current and mean power all have their uses, RMS power
does not. This is irrespective of what the application is - i.e. it is
not specific to power factor.

Whilst I don't know how your particular electric company bill you, I
very much doubt it is purely by Vrms * Irms. Most will bill by the
mean power, which is

Vrms * Irms * cos(angle between voltage and current).

So if you put a pure inductance on your system, in theory you would
not pay any electricity


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