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Re: transformer measured L, etc.



Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <teslalist-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
 >
 > Original poster: "Matthew Smith by way of Terry Fritz 
<teslalist-at-qwest-dot-net>" <matt-at-kbc-dot-net.au>

 > Still can't get over those MOT's having a calculated primary loss of
 > 600W!  (Calculated as VV/Zp).

Because Zp is mostly inductive, and so this input "power" is mostly
reactive. The power supply usually has a power factor compensation
capacitor, that "supplies" all the reactive "power".
To obtain the real input power with no load at the secondary,
measure the input inductance L and the input series resistance Rs,
and then  convert the resistance to an effective parallel resistance
at 60 Hz: Rp = Rs * (Q^2+1), where Q = 2*pi*60*L/Rs.
Divide then the square of the rms value of the input voltage by Rp
to get the real input power.

Antonio Carlos M. de Queiroz