Smart-UPS 3000 XL Battery capacity issue

[Anonymous user]

I just installed a Smart-UPS 3000 XL with a battery pack.  At first it had 1:30 of runtime.  I did a Runtime callibration and it said completed after a few hours but battery capacity still continues to decrease.  It got down to 4% capacity and bounced between 4-5%.  I did a Self test and it seemed to raise the capacity a few percentage points but imediately started decreasing again.  I did a few self tests and got it up to 46% but now down to 26%.

Has anybody seen this before and if so what do you recommend

[Anonymous user]

Some questions:

1. Does the UPS know that it has the external battery pack attached ? (this has to be programmed, either via the web interface if you have a management card, or with the "Battpack.exe" on floppy )

2. How old are the batteries and how long ago was the last calibration done or was one ever done ? ( that date is also available via web interface/management card)

I've never heard of anyone doing multiple self tests in succession but maybe it is kickstarting the UPS charging circuits briefly...but if the ups doesn't know it has an external pack, or if the UPS' battery constant is out of whack that could be causing issues, or there could be a weak battery cell or two in the string.

If there is a weak/dying battery in one or two of the indivudual RBC105 modules (is it an SUA3000 RM Smart UPS XL ?) it would badly drag down the battery string voltage at the UPS and that would be seen as lower charge %.

One or two checks you could physically do are:

Disconnect the external battery pack and see if the charge level starts rising or goes back to normal - that would point to the external pack being bad.

You could also disconnect the battery modules individually (will be three if its a rack mount with external SUA48 pack ) and test the voltage across that module's battery connector. A fully charged module should read around 50.5 volts DC....a discharged module would be hovering around 48 volts DC. A module with a bad cell would read less...

[BillP · Accepted solution]

Battman covers it, check for the float charge of 54.65 volts (Should be 54 volts +/- .5V)

I have a SU3000NET that had a bad battery from the set of four batteries, caused infinite problems.

Also, does the unit run the fan when the battery is low?