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PFC CAPS
> Do you use the caps in parallel to nullify the inductance? If
> so, then I guess one way to do this would be to look at the
> current and the voltage going into your (neon sign) transformer
> and adjust the capacitance so there is no current lag or lead
> compared to the voltage?? What other ways are there to check
> this that don't need a dual trace oscilloscope and a current
> probe?
Two ways:
First use the formula...
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The formula used to determine ballpark pfc is as
follows:
9
10^
C = Corrected kVA ------ 2
2(pi)fe^
This should read C = Corrected kVA times (10 to the ninth power)
over, (2 pi times f times e squared)
C = required capacitance in microfarads
f = frequency of applied voltage
e = applied voltage
CORRECTED KVA is determined by dividing the volt*amps (watts)
output of the neon sign xfrmr by 1000
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A second way to correctly apply PFC capacitors to neon sign xfmrs
is to set up an ammeter in series with the neon primary. Add PFC
capacitors across the primary until the current drawn by the
transformer is in line with the power required to achieve the
rated output.
Another way to look at this: A 360 watt neon used as a Tesla
power supply will typically draw 720 or more watts out of the
wall if you check the draw with RMS volt and ammeters. Add PFC
capacitance until the RMS draw shown by the meters is close to
the rated output of the neon.
This correction is not required on non-shunted, or externally
limited transformers.
... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12