In article ,
M Berger wrote:

I've never seen a Liebert fail! Since it trips the DC
breaker, and assuming the batteries and float voltage
are ok, then the inverter is probably drawing too much
current -- maybe shorted output transistors.

ml wrote:
i got a 6kv liebert ups, trips the dc breaker on testing fail to backup

never worked on a ups before, i can say the ac side seems to be ok,
and the charger seems ok as the batteries stay floated /charged front
pannel lcd seems to work

any clues what might be a good path to start on or perhaps someone might
know what these ups typically blow?


thanks

yeah thanks v much, usually they are pretty good, wish i had the
manual, at first i figured perhaps i didn't set it up right, but the
place that discarded it said the repair guys said it wasn't worth
repairing. the batteries for sure are fully charged and float ok

if it's not getting ac, it won't ever power it just shuts off, fooling
w/the pannel trying to 'turn it on' dc testing etc just trips the
breaker(dc)

appreciate the tips i'll poke around a bit more