Computer room Power Factor

[sibeen]

I'm trying to track down some 'historical' figures on what the normal rnage of power factors could have been expected in large computer/data centres, approximately 10 to 15 years ago.

It's one of those things that I used to have a heap of reports on, but that was two or three employers ago, and I no longer have the information to hand.

I'm currently writing a report and want to show the trends of the power factor in these rooms over the last 15 years, and the effect this has had on UPS sizing etc.

Any links or other data would be appreciated.

 

[ScottyUK]

Have you tried Gambica in the UK? They likely have the information you want but equally likely will charge you for it. Possibly ERA Technology at Leatherhead - this was their kind of work years ago when I worked there although I think they've steered away from the traditional power and plant sectors lately. ERA would likely charge you too.


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If we learn from our mistakes I'm getting a great education!

 

[7anoter4]

I suppose you seek for specific losses. I don't know if for UPS dimensioning the heat losses are significant but for HVAC was. As I was the designer I am not sure that this maximum and minimum specific losses was the actually ones –nevertheless the HVAC people was very interested in accuracy and nor Power Station people neither HVAC people did not complain.
There are the following lines:
For a Relay or Control Cabinet normal losses per sqr.m of enclosure front surface are 323 w/sqr.m[an average value].
For a Distribution Panel 3000 w/cub.m [per total volume].
Relay Room- the lighting losses per room floor surface sqr.m are 20 w/sqr.m.
Control Room- the lighting losses per room floor surface sqr.m are 30 w/sqr.m
Relay Room total specific losses =Max. 530 w/sqr.m Min. 150 w/sqr.m
Control Room total specific losses =Max. 600 w/sqr.m Min. 200 w/sqr.m
Since the equipment mounted in a Relay Room and Control Room was very sensible to room temperature the Air Conditioning was the main consumer of a UPS.

 

[alehman]

It is hard to generalize. Power factor depends on the types of UPS systems, HVAC systems and their loading. Assuming no power factor correction, pf can range from 0.8 lag to 0.95 lead. For a well loaded facility maybe 0.85 lag to 0.95 lag.

 

[sibeen]

Oops, I may not have been clear eneough with the opening question.

I'm trying to show the trend in the PF of computer power supplies in large data rooms, so the output load on the UPS.

Basically I want to show some form of trend line showing how the loads on UPS systems have gone from approxiamtely 0.8 lagging to nowdays, with PF corrected supplies, the PF on the output of a UPS is now close to unity, or in many cases has actually switched to being a Leading PF.

 

[alehman]

I don't have any data for you. You might consult with a power supply manufacturer or UPS manufacturer.

You could also try 80plus.org

http://80plus.org/