I know this is OT for the Soekris list, but folks here seem resourceful, 
and the question is caused by my Soekris.  What is a good source for 
rackmount enclosures for UPS-style batteries, and for a 12V UPS 
switch/control?

Right now, my home infrastructure (a Soekris 5501 with external disk 
drives, and a handful of other network components) runs on a variety of 
12V wall warts, all powered off a 3KVA rackmount UPS, even though it 
only consumes about 60W.  This is a great big mess, large, not power 
efficient (the UPS wastes more than it outputs), and generally ugly.  So 
I'm going to organize it.

Step 1: Build a custom 2U rackmount case for the Soekris 5501, booting 
either from a small SATA SSD (solid-state disk) or from CF, with two 
external large SATA disks using a PCI SATA controller, and with a 
miniPCI 802.11 card.  The whole thing gets powered by 12V (with the disk 
drives having their own 5V and 12V DC-DC converters, not using the 
Soekris internal supply).  I'm resigned to having to custom-build my own 
19" rackmount case, which is not difficult, just tedious (saw, file, 
sheetmetal work, spraypaint, done).  I'll start with a generic 2U 
rackmount enclosure from Digikey or such, and use standoffs to mount the 
whole Soekris enclosure (with lid removed) inside it; this removes the 
need to make individual cutouts for all the connectors on the Soekris board.

Step 2: Take the existing lead-acid batteries (all 12V 7.2Ah, some from 
the existing UPS, some from a homebrew 12V UPS), and mount about 8 or 12 
of them in a rackmount enclosure.  This gives me enough capacity to get 
through a whole night.  Does anyone know where I can find a rackmount 
enclosure that is designed to hold lead-acid batteries?  Given that this 
works out to about 60 lbs, starting with a generic 3U enclosure and 
modifying it myself is likely to be work.

Step 3: Build the electronics for a 12V 60W UPS (with some headroom, say 
size it ).  This seems to be easy: start with a 13.8V power supply 
(Astrodyne has those in reasonable sizes), and add the failover switch / 
charger combination; a little web search finds suitable units for 
example from www.powerstream.com or www.transtronics.com.  Do people 
have recommendations on which modules to use?  Then building a pseudo- 
PDU (a bunch of fuses and connectors) is easy.

Step 3: Wire it all up in a small 19" rack.

Suggestions? Criticism?

-- 
Ralph Becker-Szendy    [email protected]            (408)395-1435
735 Sunset Ridge Road; Los Gatos, CA 95033
_______________________________________________
Soekris-tech mailing list
[email protected]
http://lists.soekris.com/mailman/listinfo/soekris-tech

Reply via email to