1 Why isn't my UPS turning on?
I have a Powercom BNT V1.3 UPS, which I got from my uncle. It's a line-interactive model and decades old. Other than its obviously dead battery, it was working fine when I first received it.
What I Did
Since the battery was dry, I attempted to revive it by adding water to the cells. Afterward:
- I reconnected the battery.
- I turned the UPS on to start charging the battery.
Unfortunately, after charging for a while, I heard a pop and saw a flash of light. I immediately turned the UPS off and noticed the smell of "magic smoke" from one of the components.
I later found out the battery had an internal short. Since then, the UPS hasn’t started.
What I’ve Tried So Far
- Tested the transformer for continuity: it seems fine.
- Fixed two broken traces on the back of the circuit board (see images below).
Images
What Should I Check Next?
I am unable to identify which component might have failed. Any advice on what to check next or how to proceed would be greatly appreciated!
Notes
- The UPS has not turned on since the incident.
- I suspect some components may have been damaged, but I’m not sure which ones.
crwdns2934109:0crwdne2934109:0
crwdns2889612:0crwdne2889612:0
0
Usually capacitors in old equipment go "pop" first. But it looks like you've checked them?
From your photo transistor Q23 looks dirty dusty. Maybe it shorted?
crwdns2934271:0crwdnd2934271:0 Allen crwdne2934271:0
@nest2g
I'm fairly new to fixing my own equipment, I haven't checked the capacitors yet, since none of them look bloated or like they're leaking (Also no component has visual cues pointing to a failed component, other than the slight blackening on the circuit board probably due to heat). Will need to individually check each component over the weekend.
crwdns2934271:0crwdnd2934271:0 Dominic miranda crwdne2934271:0