[Veering off-topic; mods, I'll not continue this branch of the thread much longer....]
On Friday 14 September 2007, John R Pierce wrote:
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).
Input power not a problem; we have a 125KVA Leibert PDU for the server room (about 4,000 square feet raised floor with 30 tons of A/C (Leibert System 3 15 ton x2)). There are a few L21-30R's, L5-30R's, and L6-30R's under the floor.
(googles, oh. 12V 75AH monsters, online looks like $125 each).
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.
You've just described the way our 48VDC system is connected, with the exception of the type of battery...we have a bank of 24 C&D KCT-450's for 48VDC, with two Lorain RHM200D50's floating them (cells and rectifiers were donated to us). The cells are in an old munitions building that was on-site (please don't ask; look up our history on www.pari.edu....:-)) that we moved from the pistol range to the back of the main building, and ran four 2/0 'jumpers' to.
But if someone wanted to support an educational institution and wanted to lease floor space and/or bandwidth (we currently have 100Mb/s to the Internet, and an OC3 to our co-lo in Asheville (also our ISP's PoP; see www.ercbroadband.org) (which is part of the reason my equipment budget is so lean!)), we would love to talk. Perhaps even for CentOS mirroring and/or building.
Peter Arremann visited us a while back (by the way, Peter: good article in LJ, and thanks again for the UltraSPARC goodies!); he could fill you in on how it was when he visited.