When you (eventually) have to replace them
I'm on my third set of batteries now...
save the "wiring block" (I'm glad YOU gave it a name; I'd have just
called it a "plastic thingy that goes between them" : ).
Yeah, I didn't know what else to call it.
You need to *slide* it ALONG the top of each battery to disengage
the FastOn's from the battery.
Mine has short jumper wires inside the wiring block. When I remove the tape
holding the batteries together, I can seperate the batteries enough to
reach in and disconnect the terminals.
Thankfully, my new batteries came assembled as a unit with a new wiring
Of course, depends on your load. E.g., the XS1500 that powers my
monitors will keep them running for almost a DAY -- if they are in
StandBy mode! : But, once lit up, the runtime estimate drops to ~20
When I replaced my UPS batteries, my computer setup was using about 90
watts (CPU, monitor, cable modem, router, and phone adapter). I was able to
run a bit over 70 minutes on battery power.
A couple weeks ago I bought a new monitor and the total power draw dropped
to about 70 watts. My UPS claims I can run 90 minutes now, but I haven't
tested it since changing monitors.