telehouse - 25 broadway

Sun Sep 16 15:23:27 UTC 2001

On Sun, Sep 16, 2001 at 11:10:30AM -0400, David Lesher wrote:
> This is just as much a case of matching equipment to application
> as is buying a new backbone router. Do you buy based on a "100 year
> flood" peak; the "Mothers Day calling" peak or the "105% of >1hr"
> model. Justify your decision the the beancounter. 25 points.

Every time I've seen a standby generator sized for a computer data
center the 'continuous run' figure was used for the maximum loading.
Data center loading is generally fairly well known, if you have a
N KW UPS, it's known to draw N + M KW on input at full load, and the
generator needs to be able to supply N + M for continuous run.

Overrun amounts are _very_ limited.  Typically < 30 minutes @10%
over, and < 5 minutes @20% over.  I don't think I've ever seen one
with a rating for more than 20% over.  Even a bean counter won't
expect a power outage to be over in 30 minutes.

-- 
Leo Bicknell - bicknell at ufp.org
Systems Engineer - Internetworking Engineer - CCIE 3440
Read TMBG List - tmbg-list-request at tmbg.org, www.tmbg.org