Powerware 9120 5KVA UPS DC Bus Fault

[alltvrepairs]

Hi,

I have the 5KVA model with the common DC Bus Fault. Have thoroughly followed this thread. My main board is more complicated. I have changed the capacitors marked in RED near the DC-DC section.

Anyone was able to find a schematic or give some advice. Its a pity not being able to fix this old but good UPS.

PSDR-1112NN

Thanks!

[SGR]

Re: Powerware 9120 5KVA UPS DC Bus Fault

Hello, could you solve this problem?

[sam_sam_sam]

Re: Powerware 9120 5KVA UPS DC Bus Fault

Hi,

I have the 5KVA model with the common DC Bus Fault. Have thoroughly followed this thread. My main board is more complicated. I have changed the capacitors marked in RED near the DC-DC section.

Anyone was able to find a schematic or give some advice. Its a pity not being able to fix this old but good UPS.

PSDR-1112NN

Thanks!

You might also want to change all the small UF value caps as well
Because those are first to become a problem before the higher value caps do

Also look for any IC chip that are switching power supply or buck switching power supply IC chips or boost power supply IC chips or superior chip of any kind change any caps near those IC chips or any those types of IC chips might bad as well

I hope this helps