Is My BX1500G UPS Bad -- Logic Problem?

[Anonymous user]

This is not the usual battery blinking or unit reset issue, so please read further. I'm very technical, so you don't need to hold back on the tech lingo.

I own two BX1500G UPSs. Both have brand new APC battery packs (12v/9ah). I have swapped the battery packs several times (unit 1 to unit 2 and vise versa) and always have the same results as described below. It appears to be a logic issue.

Condition

• First UPS works fine. The display consistently shows 66 minutes of available battery time based on the load and a fully charged battery. It passes the self test. Actual battery discharge matches the predicted value on the display.
• Second UPS always shows full charge, but 1 minute battery availability. A self test fails about 50% of the time. The display shows a bad battery 50% of the time. Resetting the UPS doesn't change the behavior. Swapping the battery pack with unit 1 produces the same results on both units,. Actual discharge of this unit is longer than the display value, but I haven't actually timed it past 5 minutes.

Additional Detail

• Sometimes the second UPS display shows 1/4 charged battery after a power cycle -- even though the battery is fully charged. If left powered on, the battery meter will eventually creep up to 100% over over several hours. The available battery time goes from 0 mins to 1 min. 
• PowerChute shows unit 2's battery is 100% charged.
• Unit 1's firmware is 866.L9.D
• Unit 2's firmware is 866.L8.D

Bottom Line

My batteries are good. The second UPS shows a fully charged battery, but only 1 minute of discharge time. Swapping the batteries with a known good UPS produces the exact same results. This feels like a logic problem. 

Can someone comment here. Also, how do I get the UPS up to the newer firmware?

[Anonymous user]

I had a similar problem with a new battery pack.

Did you use Powerchute and update the last battery changed date? That fixed my problem.

[Anonymous user]

Thanks for the tip. That did the trick, although I'm not sure why the battery change date has anything to do with the calculation of discharge time. What it tells me are two things:

1. The displayed battery run-time and related alarms/warnings is akin to my refrigerator barking to change the water filter. It is just a timer that assumes certain performance/longevity behaviors when I press the reset button (in this case, update battery change date). With this logic, I could install a year-old set of batteries (still good) and the UPS will display the same metrics as a new set. 

2. The batteries numbers on the front display are relative, not absolute -- and, therefore, not believable. 

Does anyone know who to upgrade the firmware in this UPS? If it means opening the unit and plugging in somewhere, I'm good with that. I just need the file and instructions.

[Anonymous user · Accepted solution]

---correcting a type-o---

Does anyone know how to upgrade the firmware in this UPS? If it means opening the unit and plugging in somewhere, I'm good with that. I just need the file and instructions.