I'm just reviewing a 120W psu spec. In the EU this would require power factor correction for the input. The spec I have doesn't mention it but does refer to MIL-STD-461.
I've had a quick search of the pdf for 461F doesn't mention power factor correction. So does the US care about PFC on power supplies? Or is it known by another name?
Raveninghorde wrote: > I'm just reviewing a 120W psu spec. In the EU this would require power > factor correction for the input. The spec I have doesn't mention it > but does refer to MIL-STD-461.
> I've had a quick search of the pdf for 461F doesn't mention power > factor correction. So does the US care about PFC on power supplies? > Or is it known by another name?
On Tue, 03 Nov 2009 12:31:53 -0700, don <don> wrote: >Raveninghorde wrote: >> I'm just reviewing a 120W psu spec. In the EU this would require power >> factor correction for the input. The spec I have doesn't mention it >> but does refer to MIL-STD-461.
>> I've had a quick search of the pdf for 461F doesn't mention power >> factor correction. So does the US care about PFC on power supplies? >> Or is it known by another name?
On Tue, 03 Nov 2009 19:50:08 +0000, Raveninghorde wrote: > On Tue, 03 Nov 2009 12:31:53 -0700, don <don> wrote: >>Raveninghorde wrote: >>> I'm just reviewing a 120W psu spec. In the EU this would require power >>> factor correction for the input. The spec I have doesn't mention it but >>> does refer to MIL-STD-461.
>>> I've had a quick search of the pdf for 461F doesn't mention power >>> factor correction. So does the US care about PFC on power supplies? Or >>> is it known by another name?
But seriously, sometimes you'll see rectangular cans on the power poles; they tell me these are capacitors to correct for the power factor of inductive stuff, like refrigerator motors and A/C motors and stuff.
But I've never heard of a requirement for PFC (power factor correction) on stuff for household use. Industrial, I haven't investigated, but they do have a lot of inductive loads, but you'd probably work that out with your power company guy.
>I'm just reviewing a 120W psu spec. In the EU this would require power >factor correction for the input. The spec I have doesn't mention it >but does refer to MIL-STD-461.
>I've had a quick search of the pdf for 461F doesn't mention power >factor correction. So does the US care about PFC on power supplies? >Or is it known by another name?
>On Tue, 03 Nov 2009 19:50:08 +0000, Raveninghorde wrote: >> On Tue, 03 Nov 2009 12:31:53 -0700, don <don> wrote: >>>Raveninghorde wrote: >>>> I'm just reviewing a 120W psu spec. In the EU this would require power >>>> factor correction for the input. The spec I have doesn't mention it but >>>> does refer to MIL-STD-461.
>>>> I've had a quick search of the pdf for 461F doesn't mention power >>>> factor correction. So does the US care about PFC on power supplies? Or >>>> is it known by another name?
>But seriously, sometimes you'll see rectangular cans on the power poles; >they tell me these are capacitors to correct for the power factor of >inductive stuff, like refrigerator motors and A/C motors and stuff.
>But I've never heard of a requirement for PFC (power factor correction) >on stuff for household use. Industrial, I haven't investigated, but they >do have a lot of inductive loads, but you'd probably work that out with >your power company guy.
>Hope This Helps! >Rich
Over here almost any PSU over 75 Watts (from memory) needs to be unity power factor. That is sinusoidal current consumption in phase with the voltage.
So for the EU I need a more complex PSU than some other countries. This project is for Asia but calls up US military standards. The only place the requirement could be hiding is in 269 pages of the EMI/EMC spec.
> I'm just reviewing a 120W psu spec. In the EU this would require power > factor correction for the input. The spec I have doesn't mention it > but does refer to MIL-STD-461.
> I've had a quick search of the pdf for 461F doesn't mention power > factor correction. So does the US care about PFC on power supplies? > Or is it known by another name?
Is it a military PSU? If they're quoting MIL STD 461 for EMC, it probably is. The relevant document for electrical supply quality is then MIL STD 704(F?) by association. It says there is no need for power factor correction below 500watts. The only noteworthy comment is that you can't use half-wave rectification. Don't laugh, I know someone who did.
>> I'm just reviewing a 120W psu spec. In the EU this would require power >> factor correction for the input. The spec I have doesn't mention it >> but does refer to MIL-STD-461.
>> I've had a quick search of the pdf for 461F doesn't mention power >> factor correction. So does the US care about PFC on power supplies? >> Or is it known by another name?
>Is it a military PSU? If they're quoting MIL STD 461 for EMC, it probably >is. The relevant document for electrical supply quality is then MIL STD >704(F?) by association. It says there is no need for power factor correction >below 500watts. The only noteworthy comment is that you can't use half-wave >rectification. Don't laugh, I know someone who did.
>Graham H
Asian military.
And thanks that's the answer I needed. I'll find MIL-STD-704 for reference.
>>I'm just reviewing a 120W psu spec. In the EU this would require power >>factor correction for the input. The spec I have doesn't mention it >>but does refer to MIL-STD-461.
>>I've had a quick search of the pdf for 461F doesn't mention power >>factor correction. So does the US care about PFC on power supplies? >>Or is it known by another name?
That pretty well says what is what, in the US, for regulation, however there are some limits for meeting the "energy star" compliance here. I have also seen industrial loads where the utility required active power factor / harmonic correction. Otherwise, there are requirements that are part of equipment purchases and some manufacturer's associations that are putting out voluntary compliance standards.
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