On Wed, Nov 17, 2010 at 11:56 AM, Michael Smith <[email protected]> wrote: > Hello Daniel: > Not knowing your load exactly my first inclination is that you can't get > there from here. The load from the HVAC system will be considerable, so you > would have to have a significant battery string to be able to maintain load > during an extended outage. The power fluctuations are not a problem for UPS > within reasonable limits. They all do power conditioning on input and > output power, as far as I know.
You are right, I should have been more specific. So the situation is this: 1. HVAC (heating/cooling) system approx 115V/10A 2. Everything else (computers, monitors, emergency lighting) approx 115V/8A 3. Not in a situation where I can install a generator of any type 4. Eventually will have "normal" power, but for a while it'll be very intermittent, approx 16h with power every day, and 8h without. Would prefer not to spend money on two different systems if at all possible, but based on your email looks like there may not be a choice (eg perhaps I should look into whatever battery systems are used with solar panels or something like that, and then have a UPS system in front of that.) > How much load are we talking? You basically need to get the load for all of > your devices and then use the manufacturers specifications to determine how > much runtime you'll get from a particular unit. > In general, the normal configuration would be to have enough UPS available > to get you to generator power so that you don't have to go to battery too > often or for too long. You will end up replacing a *lot* of batteries if > you're running them for hours at a time on a frequent basis. Yeah, a lot of the question is if anyone knows what types of batteries work well with heavy use; I'd assume lead-acid are pretty good, but don't know about other types. > -- > Michael K. Smith > [email protected] > > > > On Nov 17, 2010, at 08:43 AM, Daniel Clark <[email protected]> wrote: > > Looking for a UPS system that: > > 1. Runs off of US 115V / 20A > 2. Can handle frequent extended power outages while continuing to > provide power to computers and HVAC systems (so amp spikes will be > common) > 3. Preferably is expandable (I'd prefer stackable to rack mount, but > not a big preference) > 4. Isn't insane-loud > > Anyone have anything they like? > > I'm sort of tempted to do http://www.dansdata.com/diyups.htm but if > there is something COTS that is somewhat price-competitive with that > I'd prefer it for safety reasons. > > But in general just general recommendations would also be great, as I > haven't dealt with UPS systems larger that 4u units in the past, and > the ones I did use I wasn't really impressed with (insert horror story > about spending hours and waiting weeks to get replacement batteries > for MGE UPS units here.) > > Happy Hacking, > -- > \|/ Daniel JB Clark | Activist; Owner > FREEDOM -+-> INCLUDED ~ http://freedomincluded.com > /|\ Free Software respecting hardware > _______________________________________________ > Tech mailing list > [email protected] > https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech > This list provided by the League of Professional System Administrators > http://lopsa.org/ > _______________________________________________ Tech mailing list [email protected] https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
