what kind of UPS will work best?

Pieter de Goeje pieter at degoeje.nl
Mon Oct 8 01:18:48 PDT 2007

On Sunday 07 October 2007, Gary Kline wrote:
> 	First, thank to both you and Bart for your cmments.  You were
> 	*right* about the price.  Can I assume that a ballpark would be
> 	400W for each server?  (My wife is right: I've got to cut back to
> 	three computers:-)  I've found one APC 2200VA with a 17minute
> 	uptime.  3 times 400W, yes?

I think this is overkill. Some time ago I was wondering the same thing and to 
verify my guess on the overall power usage of my servers I bought a VA/Watts 
meter (EUR. 39,-). Turns out average wattage is about 90watts per server idle 
and max 130watts under load. On powerup they will use a max. of 180watts for 
less than a second. The servers are simple dual cores with about 2 harddisks 
each. (no screens or other devices attached) Also, the powerfactor was ~0,95 
so that means that for every Watt of apparent power (VA) almost a Watt of 
real power was used. Thus, for my servers I would need something like a 
500Watt/600VA UPS.

So my advice is: don't guess but measure.

Pieter de Goeje

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