SUA1500I UPS dead - beeps continuously & smells like hot electronic

[Anonymous user]

Hi, I bought the UPS a few years ago (the PCB says 2004) and hooked it to my server cabinet.

I disconnected the unit 4-5 months ago because I had to fix some problems with the servers and didn't need the UPS. About six weeks ago I used the UPS for a few days and everything was fine.
Yesterday I hooked everything up again but the UPS didn't power up.

The battery is ~80% charged and can power a 24 volts light-bulb with no problems or noticeable voltage-drop.

To do some tests, I removed the circuit board from the case and placed it on my table. (Don't worry, I know what I'm doing here and have the right equipment)
I use a 30V / 3A adjustable power supply to do my testing, so a dead battery is no option.

If I try to turn the unit on, the LEDs stay dark and it beeps continuously. 20 seconds later the sound changes, it sounds like the voltage isn't stable/noisy and dropping.
One of the voltage regulators is getting hot and smells bad so I didn't test this for a longer time.
Two relays switch as I apply power, but the switching noise is missing this "crisp" sound, don't know how to describe it.

Now I really need your help. The unit is already out of the warranty time and my distributor doesn't offer any help/repair service.
I can provide measurements, pictures etc, feel free to ask.

Thank you!

[BillP · Accepted solution]

The only out of warranty repair/service company that's certified by APC is [Coastal Business Machines|http://www.buyupsonline.com]: 888-234-9877

You could try giving them a call perhaps... APC won't help you tear apart the insides or replace those internal components.