On 08/26/2010 01:24 PM, Corey Edwards wrote: > A generator won't solve your problem without a UPS. It takes up to a > couple minutes for the generator to kick on and switch over. During that > time you need a UPS to carry the load. There's really just no way around > it. Preventative maintenance is your best bet.
Generators bring some interesting things to the mix. As you say you can't have a generator without a UPS. But the UPS has to be pretty smart when switching back and forth between line, battery, and generator. Not only does the UPS have to carry the load while the generator gets up to speed, it also has to match phase with the generator. This doesn't take very long, but you have to have a pretty expensive UPS to do this. Then when line power returns, the UPS has to carry the load again while it adjusts the phase to match the line phase. We have a nice big, in-line UPS at work that does all this. Works well if you have the resources. The reason that some cheap (and very expensive) UPS's kill the load when the battery dies is that to avoid all this phase-matching nonsense, some of them just run the power through the batteries at all time. In other words you're running AC->DC->Battery->Inverter->Load. /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
