I have APC SU1000NET smart UPSes on 3 servers plus 1 diskless server and an occasionally active server that is used for backup purposes.
I am not satisfied with the run time. A half an hour or even a mere 5 minutes is not enough with most major power outages lasting 1 to 4 hours. Typically, a squirrel flips the power company breaker or there is a snow related outage. The service is fairly reliable, but there are power outages. There is natural gas service for backup heating, but generators are really expensive and with 200 amp service, I guess I would need a fairly large generator. I have a deep cycle marine battery that I picked up, but I'm wondering if I can even use it as these produce hydrogen gas when charging. How much gas and how much ventilation is needed to disperse that gas? I am after supplemental power so that my UPS'es will run longer. So how do I set up the AC circuit and what do I need to effectively keep the batteries I pick up from being drained all the time and prematurely worn out? How do I set things up, I have an inverter, so that the inverter kicks in and dumps power into the rest of the AC line (not the breaker box) during a power outage? I understand with wet cell lead acid batteries that they can be reconditioned. Sealed lead acid batteries are not repairable, at least without special equipment they aren't repairable. How many batteries will be needed to provide 1-4 hours worth of power to four to six computers, one digital answering machine, and one cordless phone? Is a 600 watt peak inverter too small and should I buy a bigger one or more of them? If I go from one battery to more than one, do I need a charger for each battery? Essentially, I want to build a very simple UPS. Charge batteries and feed AC power to the rest of the circuit when the power is on. When there is a blackout, power the rest of the circuit (not the breaker box please) using stored DC power and an inverter(s). I don't care about smart signal schemes, though I might need a micro controller of some kind and I might run embedded Linux on it. I estimate on a bad day that a computer will consume about 300 watts and I have 4-6 of these at any one time running on the circuit plus a cordless phone and a digital answering machine. A conservative estimate is that I need to provide 1920 to 2k watts for 1-4 hours. That is most likely an overestimate though. Thoughts? Just from my power need estimate, I figure that translates to four 600 watt inverters (not grid tie). Additionally, four batteries will be needed to feed those inverters at $80+ a piece. I figure I can pick up Cobra 600 watt inverters for around $69 a piece. I already have one marine wet cell battery and one 600 watt inverter. I'm looking at about $500 in additional batteries and inverters plus whatever it costs to build the necessary circuity to make this all work. _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
