APC ups smt1500rmi2u battery fault

[Anonymous user]

Hi all i recently had a fault with my ups indicating my batteries were due a replacement or faulty, so i bought some new ones got them installed upon resetting the ups the red battery fault was still there the unit would not pass it's self test and was still telling me the new batteries were also faulty after a quick call to APC i was advised that the new batteries must have been faulty because they were not genuine APC Replacement's and i should get more replacements so a few days later another set of new batteries arrives. So i installed them rebooted the ups and and still got the same battery fault left it a few days no change another quick call to APC suggested i buy genuine batteries' at 3 x the cost and my unit would function normally i explained the batteries were brand new and tested via other sources and found to be in full working order to which is was suggested my UPS may be faulty and i could follow the exchange program for a new UPS. So at this point i had 3 sets of batteries which were all working fine but a UPS telling me otherwise.

So i contacted a few companies to get quotes to see about getting it fixed they came back with very similar prices of around £300.00 to restore my UPS to full working order now either the upgrade program or the cost of repair seemed very attractive at this point so i thought what the hell lets take a look i side and see if i can fix it.

After spending very little time checking the most obvious things i was about to give up when i accidently caught the the end of mains plug and got a shock hmmm odd the current from the batteries is actually flowing back into the utility mains that's not right a multi meter also confirmed this so after a little more digging i followed the circuit to a Relay (894H-2AH1-F-S 24vDC) so i removed the relay and indeed it was faulty so i ordered a replacement for 89P installed it and the ups is working fine and passes all self test's and with the original batteries installed.

So i saved my self the cost of a £700 upgrade or £300 repair.

One way to test if this particular relay has failed on this unit is to test the main's plug outlet with a multi meter while running on battery if there is a current the relay has failed and they can be found on the net for very little.

Hope this helps anybody with a constant battery fault problem.