Topic: APC SUA750 UPS

[George Richardson]

Hello,
Hope someone is more familiar with these units than I am. I just put a reconditioned unit into service hooking up about 350 watts to it. The load lights functioned properly, lighting 3 of 5 lights but the battery charge lights (all 5 lit with a full charge) flashed repeatedly until I disconnected the 32" flat screen that was drawing 125 watts. Anyone know why a 500 Watt APC UPS won't handle 350 watts?
TIA
George

[vreihen]

UPS units are rated on volt*amps, not watts.  I have no idea what the power factor is for one of those units, but you can probably find a web site with actual UPS watt capacity ratings out there somewhere in the ether.....

[DanS]

Maybe the battery(s) condition? Weak cell? I have an UPS that used to do that and kept going through batteries until I found that the charging circuit was slightly over charging and killing batteries. Before it was almost a yearly thing swapping in a new battery now (after tweaking the charge circuit) it's been over 3 years and still going.

[Garth Bock]

I found this...hope it helps....

http://www.apc.com/us/en/faqs/FA156538/

[George Richardson]

Garth,

Thank you so much. That is exactly what I was looking for (I think).

Some folks are very good at finding things on the internet, I'm not. I really appreciate your bird dogging this for me. While Dan's post may be relevant, I hope not but I thank you anyway.

Again, Thank you, everyone.

George

[Garth Bock]

You're welcome. It sounded familiar to me. At the university we had the older cream colored ones APC 450 which started doing that after 3 years. It was the years where my IT dept repaired rather than replace. The batteries the electrical dept put in were a different make and APC told us to flash the firmware because the charge circuit was detecting a difference. This worked on almost all of them except a couple had bad charge circuits.

[George Richardson]

Garth,

Now, faded memories start floating back. Old cream colored units. Ah. It seems to me that I remember something about a piece of black tape covering miss-behaving lights. Don't remember results but it must not have been catastrophic.

At this point, with my present configuration, I think I'll just live with a lighter load for a while.

George