[CentOS] Re: centos] CentOS 5 on IA64

John R Pierce pierce at hogranch.com
Fri Sep 14 15:59:36 UTC 2007


Lamar Owen wrote:
> If someone would like to donate a midsized 208VAC-capable (single-phase OK, 
> but has to be 208 and not 240, or at least jumperable) UPS to the effort, 
> about a 3000VA unit or so, that would help matters considerably!  All my good 
> UPS's are 120VAC at this point (my one good 208VAC unit threw a battery a few 
> weeks ago; 8 12-270 UPS batteries will blow my equipment budget right now...
>   


I've gotten away with running some 208V equipment on a 120V UPS using a 
step-up transformer which had a 208V tap (and 220V, 240V).  Of course, 
3000VA is going to require a 120V 30A outlet to power said transformer 
(and a UPS with 30A output probably needs a 50A circuit to feed it).

what size are those 12-270 batteries?    I replaced the 12V 17AH 
batteries in a SmartUPS 2000 with Panasonic 12V 20AH from 
www.Digikey.com for relatively cheap.    (googles, oh.  12V 75AH 
monsters, online looks like $125 each).

Another alternative is to get Marine/RV batteries from Costco or similar 
discount store, 12V 100AH  for about $50 each, and string them in series 
external to the UPS.  you need to use VERY heavy gauge wire for this, 
like automotive jumper cable diameter.   I'd put said batteries in a 
series of battery boxes, and install the whole mess some place like the 
basement, with ventilation to prevent accumulation of hydrogen fumes.



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