On Jul 8, 9:53*am, Winston wrote:
On 7/8/2010 5:24 AM, Lloyd E. Sponenburgh wrote:

*fired this volley in news:2d790886-
:

So the temporary fix is to add a 40 ufd run capacitor in parallel with
the motor. *That corrects the power factor a bit and drops the current
enough that the circuit breaker does not pop. *The savings in power is
pretty much nothing, but having the power stay on is priceless.

Dan,

I know it would be much more expensive, but how about an active power
factor controller? *That would handle correction at all loads, and also
wouldn't present that potential "dead short" across the line, should the
cap decide to upchuck.

I stumbled across this Power Factor info just now:http://ecmweb.com/power_quality/reso...esonance_0301/
It is a cogent read, notwithstanding the equation error on page 1
under "Harmonic and reactive currents".

[Reader's Digest Version:
Low PF can *also* be caused by a 'current resonance' in the
load, which can also have the effect of distorting the voltage waveform.
(This is in addition to the more traditional 'impedance mismatch' cause
of low Power Factor, addressed with parallel capacitance.)]

If you had a nifty Hall Effect current adapter, you could clamp it on to
the line supplying your drill press and determine if your DP is trying to
be a radio transmitter. *

As you see at the end of Page 1, the author suggests that an
RC filter tuned to snub the frequency of the 'current resonance' can
reduce it significantly, improving system reliability.

--Winston

Interesting. But I think that they are talking about non-linear
loads, not electric motors.

Dan