Great Thread! Just what I was looking for and some great input coming out of it.
I run a cyber cafe in Kenya and when it was first set up 14 650va UPSs were put in place to keep the 14 computers on during the regular power outages and voltage instabilities. As time has passed they now rarely hold enough power to keep some things on even to last the 3 minutes whenever the AVS triggers to protect everything from voltage instability. Hence, finding this thread...
In reading this thread it firstly became apparent that I could not do this for every UPS in it's place as is, as, it would put a lot of batteries in poorly ventilated places in order to hide them from the users... As-of-such, the obvious solution was to put them in an adjacent room where the circuit breaker is conveniently located. That said, the line from the circuit breaker box to the computers is one, and it has been said here and elsewhere that when doing such a modification that the UPS should not be overloaded irregardless of the fact that doing such modifications was to increase their capacity, it is to increase duration, but not load.
So, here are my questions...
Firstly, if I wanted to run all these UPS down the same line to maintain the computers in unison, is there anything theoretically flawed in thinking I could hook the UPS outputs all up in parallel to provide a single redundant power source that would be spread across enough UPS that the load on any individual UPS would not exceed its capacity?
Second, since the power here in Kenya is not entirely stable and there are way too many blackouts and unstable voltage situations, I was thinking I would put the AVS before the UPSs so they would be fed voltage withing the proper range, but, I'm still left worried about the UPSs capacity to charge the higher capacity deep cycle batteries that would be connected to each. Should I connect an additional charger up to each battery to decrease its charge time and to put less stress on the UPS it is attached to?
Finally, and this last question is a bit out there, but, given that I live all equatorial and most of my customers come in the daylight hours, could this setup be the first step in eventually becoming the storage facility for a solar powered system that would either augment or even replace the unreliable power system here?
Thanks!