On Sun, 25 Aug 2019 14:57:31 +0100, Andy Burns wrote:

a UPS generally does consume a background amount of power, how else do
they cook their batteries with heat?

My APC Smart UPS 700 doesn't any more. The Friday cut and the much
longer one the follwoing Mondy proved that the mods I have made to it
have stopped it killing its batteries.

It used to kill a set of batteries in around 4 years. After the last
lot almost went into literal meltdown (the smell is what alerted me)
I made some mods before putting a new set of batteries in. That was
March 2014, so without mods they would be dead or next to useless by
now.

The UPS kept everything it's supposed to up for the 20 odd minutes of
the Friday outage. On the Monday it ran for the expected time before
shuting down with low battery. The recharge time before switching
back on was as expected as well.

The mods where reducing the charge voltage, and fitting a temperature
controlled fan and possibly some tweaks to firmware settings. A
search back in here may well find more details.

The amount will vary depending whether it's an offline, online, or line
interactive type.

At a rough guess I'd say mine takes 15 W +/- 5 W.

--
Cheers
Dave.