Re: Green Apple Small Carbon

["Charlie" <charlieDOTd@verEYEzon.net>]

"Michael J. Mahon" <mjmahon@aol.com> wrote in message 
gJmdnc-iUNiSFMXbnZ2dnUVZ_qWvnZ2d@comcast.com">news:gJmdnc-iUNiSFMXbnZ2dnUVZ_qWvnZ2d@comcast.com...
> Charlie wrote:
>> "Michael J. Mahon" <mjmahon@aol.com> wrote in message 
>> EO2dnbf-V-o4B8rbnZ2dnUVZ_h2pnZ2d@comcast.com">news:EO2dnbf-V-o4B8rbnZ2dnUVZ_h2pnZ2d@comcast.com...
>>
>>>mspangler wrote:
>>>
>>>>To figure out how long my data collection Apple II would run on its
>>>>UPS, I put a Kill-a-watt meter on it. It pulls 24 VA (not counting the
>>>>monitor). My Mac mini (dual core 1.66 GHz) pulls 28 VA if the optical
>>>>drive is not running. So you're not necessarily as much greener as you
>>>>may think.
>>>
>>>I just got one of those yesterday!
>>>
>>>Did you look at the power consumption (not allowing for power factor)?
>>>(After all, the Apple II power supply was *way* before power factor
>>>correction.  ;-)
>>
>>
>> Do any computer power supplies sold in the United States have power 
>> factor correction?  I believe they are standard in Europe but I'm not 
>> sure about the US.
>
> Europe was quicker to lower the power levels requiring PFC than the US,
> but progress up the learning curve for PFC supplies, higher integration
> levels, and the economies of making "global" power supplies are pushing
> PFC into more power supplies every day.
>
> Higher powered supplies will be the first to go to PFC, of course.

Thanks Michael.  After posting I did a quick look on the net (should have 
done that first) and found several PFC supplies marketed in the US.

>> Also, in another newsgroup a poster argued that the Kill-a-watt meter 
>> isn't accurate when used with a computer due to the switching power 
>> supply.  He claimed that the Kill-a-watt meter needed a true sine wave 
>> for accuracy and that the switching power supply warped the normal AC 
>> sine wave.  I have no idea as to the validity of that argument but 
>> figured you would be the guy to ask.
>
> I don't know the circuit of the Kill-a-Watt, but, since it makes a
> distinction between watts and VA, and clearly is controlled by a
> microprocessor, it is not unreasonable that it computes using the
> actual sampled waveforms for current (if not voltage, which is almost
> always sinusoidal unless it's locally produced by an inverter).
>
> It would be possible to so some experiments to find out, but probably
> easier to try to find documentation on the design.

Yes if I recall correctly there was a discussion along those lines in the 
other group but no resolution. :-(
I really want the Kill-a-Watt to work as it seems like it does a lot for a 
very reasonable price.

Charlie