If you want EXTENDED time, wait til the batteries die, remove them and run
wires to a car battery
(can even be outside in a battery box ) DO NOT allow the internal charger
in the UPS to charge the
car battery, put a diode in line to block current going to the car battery
but allowing the battery voltage
to 'flow' to the UPS. A small trickle charger or floating battery charger
can keep the car battery at
full charge. You can use an old heavy extension cord ( like those orange
ones you get to use outside )
to connect the battery and USP. Useful backup time should be anywhere from
6 to 24 hours depending
on the draw ( how much your trying to power) and the quality ( number of
plates ) of the battery.

BE SURE the UPS uses batteries totaling 12 volts, before you even attempt
this. Any damage you cause
on your own equipment is your own fault ...... so if you don't know what
your doing don't even try.
and if you do ..... don't blame me





"Ron Hardin" wrote in message
...
Has anybody tried getting longer run times from UPS's by plugging
one UPS into another?

Power goess off, the first UPS goes on batteries, and runs everything.
When it quits, the second UPS senses it and goes on batteries, and
runs the computer.

And so indefinitely if you add more UPSs to get more runtime.

It seems it me it would work except possibly :

(1)The UPSs might not like the non-sinewave output of the first UPS, and
(2)I don't know what kind of current they draw if they decide to
recharge their batteries from an outer UPS. (This would suggest it's
wise to unplug the outer UPS when the power goes off so nobody
tries to recharge.)
--
Ron Hardin


On the internet, nobody knows you're a jerk.