DIYbanter - View Single Post - Compact Flourescent "Lamps" for Ceiling Fan(s)

Don Klipstein

In article ,
wrote:

The KAW showed a 0.57 power factor for a 14 watt Commercial Electric CF from
a recent Home Depot 6-pack, vs 1 for the incandescent. For extra credit, she
might try correcting the CF's power factor to 1 with a small parallel motor
run cap, based on the measured PF, with reactance Xc = V^2PF/(Psqrt(1-PF^2))
and capacitance C = 1/(377Xc), ie 2653Psqrt(1-PF^2)/(V^2PF) microfarads, eg
C = 2653x14sqrt(1-0.57^2)/(120^2x0.57) = 3.7 uF. Motor repair shops often
discard used motor run caps.

Will this work for an electronic vs magnetic ballast?

This will not work for electronic ballasts. Their low power factor is
mainly from the waveform (of the current being drawn) being rich in
harmonics by being far from a sinewave.

There are high power factor electronic ballasts, but most CFLs do not
have these because they cost more than the simpler low power factor ones.

- Don Klipstein )