Repeated Smart UPS 2200 and 3000XL failures

[Anonymous user]

I am the Site Manager of a remote astronomical observatory. Included in our array of many different models of APC UPS's are four 3000XL's and one 2200 rack mounted units. In the last few years, 4 out of 5 of these have gone belly up - one just today - and all due to the same basic problem similar to what is stated in another thread. The basic symptom is that at some point the unit quits working, never to be switched on again. When you do try to power it up, you get a short beep, hear the relays switch on for a moment, and the LEDs flicker. In each case, when we opened the units up, we found almost the exact same destroyed components on the motherboard:

One or more complete rows of the power transistors (8 per row) attached to the 4 large heat sinks are completely fried (melted);
The nearby capacitors in these rows are usually melted as well;
R38, R43, and R166 resistors are fried;
and one or more of the following transistors are physically blown apart: Q29,Q30, Q31,Q32, Q33.

Obviously since 4 out of 5 of our units failed in the same manner, there is a serious design flaw here! Be that as it may, does anyone have available a schematic for the 3000XL? All of these unites are now out of warranty and presumably I can repair these myself by replacing components - only using higher load ratings this time. I can go into it blind by ordering similar parts, but it would be a lot easier if I had the basic electronic road map to go by . . . .

Oh and by the way, if you happen to be around at the time of "meltdown," you will smell the results.


Thanks.

Message was edited by: gratingengine

[Anonymous user]

Just wanted to chime in and say we just had a SU2200XLNET fail similar to the OP's description.  I'm guessing the unit is 10-15 years old, S/N WS9939018786

At first I thought it was just Q33 that was blown apart, but upon further inspection, 3 of the 4 rows of heat sinked power transistors were blown open.

Data points: The UPS had been regulating a utility overvoltage condition for the past few days (this is quite common with our local utility), and the batteries were approaching 2 years of service (possibly weak battery at that point, we usually replace them at the 2 year mark)

[Erasmus_apc]

Can you provide the exact model #s and serial #s from the units?

Additionally, can you describe the load that is attached to each of the units and expand on the environment that the units are used in (input power, temperature, plug and receptacle types, etc.)?

Did you ever have any of our PowerChute software installed or a Network Management Card so that we can observe logs? All of this information will help with finding out what the issue was with the failures you have described.

[Anonymous user]

I was just about to post with the same type of problem that I have with a Smart UPS 2200. The model number is SUA2200 and the S/N is JS0544029315. The unit went out of warranty in 2007. The end user told me that it just started smoking one day, so they unplugged it and asked me to see if I could do anything to fix it. I opened it up and found 7 of the 12 power transistors burned beyond recognition. I haven't noticed any other burned components, but then I haven't cleaned the board yet to see what lies under the black residue left by the smoke.

I was wondering if anyone has had any success fixing this type of failure, and if so, I was wondering if all of the power transistors are the same P/N. Any info would be appreciated.

slinger

[BillP · Accepted solution]

Hi all, when I used to service electronics there was some successes replacing these power mosfets (RFPxxxx's etc) but these days a suspect unit that has this level of failure is sent to recycling as usually the connected equipment and the tasks it is providing are much more expensive than a replacement UPS with warranty, given that the suspect UPS might fail again.

So I am not much help, one thing I seem to recall is that the UPS is at risk of power inverter catastrophic failure when the batteries are weak, voltage drops and current spikes.

Schematics are proprietary and not available.


:-( My avatar passed away last Saturday, 01:00GMT, while on duty, we really miss her.