Re: Utility Billing KWH/ Measures in KVA but bills in kWh

On Sat, 14 Jun 2008 17:13:17 -0400, "daestrom"
<daestrom@[EMAIL PROTECTED]
> wrote:

>James Sweet wrote:
>>> The cap in A/C compressors isn't for pf, it's a capacitive start
>>> motor. Same in refridgerators, wa****ng machines, dryers, and many
>>> furnace motors. Commercial three-phase compressors used in
>>> refridgeration and A/C do *not* have any capacitors for
>>> pf-correction.  The 3-phase motors are started directly across the
>>> line.  (well, new hi-efficiency units sometimes use variable speed
>>> control, but that's another story).
>>
>>
>> Well I measured the power factor of my 3 ton heat pump and found it to
>> be .85 to .91 depending on compressor load, so the capacitor may not
>> be for PFC, but I'd still consider it to be HPF.
>
>This is a typical value for a small motor that is properly sized for its 
>load.  Really *large* motors can be as high as 0.95.  But you don't find 
>many such motors (>2000 hp) except in industry :-).
>
>daestrom


  Even a little **** machine shop with the use of nothing but "smaller"
motors has pf considerations to look at.