UPS Battery Room cooling

[j3consulting]

thread658-338980

I came across the same problem today. We were provided with the battery heat rejection data on a 15 minute and a 2 hour time frame in terms of btu/hr. The math is simple enough, and the heat balance is simple enough. However we have nothing to compare the design to in order to validate the cooling requirements. For example, 165 batteries, gel-cel, 2-hours at 110 btu/hr each = 18,150 btu/hr ~ 1.5 tons cooling, but at 15 minutes the heat rejection is much higher, approx. 600 btu/hr ~8.3 tons. I have to assume that the heat rejection is not internal to the battery itself, but to the ambient environment. Does anyone have a different opinion and other reasoning on this issue?

 

[IRstuff]

This is more of an HVAC question that probably should be posted in the HVAC forum. The only issue is whether you are willing to tolerate 15-min periods where the temperature goes higher than the set temp. You have an average, which is the 2-hr rejection, and you have a peak dissipation, which is the 15-min rejection.

TTFN
faq731-376

Need help writing a question or understanding a reply? forum1529


Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
There is a homework forum hosted by engineering.com:

http://www.engineering.com/AskForum/aff/32.aspx