Smart-UPS 1500 RM not charging

[BillP]

Hello,

recently got myself a used SUA1500RMI2U but i ran into several troubles. I plugged a new RBC24 Bat Pack into the UPS and charged it for several hours until 100% according to PowerChute SW. Then i tried to do a Self Test on the unit but then the troubles start. If i issue the Self test command the UPS switches from Line Voltage to the Bat Power and suddenly looses all energy. Bat immediately drops to 0% and the attached Device reboots due to a power failure. Same result if i try to perform a Bat calibration as soon as the Pack is back at 100%

Tried a different used Batpack with the same result.

any ideas how to fix this. Is my Unit bricked? Wonder why cause i oversaw the disassembly of this particular unit at the former site where its been used without any such troubles.

[Anonymous user · Accepted solution]

Hmmm....a couple of possibilities but mostly grasping at straws here.  First is to make sure the battery module's connections are solid, IE all the wiring interconnects  and fuses between the four batteries (via spade terminals). Sometimes a loose terminal connection will have enough metal to metal contact to faciliate low currents involved in charging but under load it can't handle the higher current and will go open circuit. Although you mentioned you tried a second module and got the same results so that is less likely to be a factor. If the UPS was badly jostled/shaken or got dropped in transit the "internal" wiring between the battery module and the main board (or other interconnects) could have gotten loosened up. An even less likely possibility is that the ups' internal "battery constant" is severely out of whack. I've "once in a long while" seen smart-ups drop loads on self test even with newly installed batteries when this constant has drifted badly over years of use. Can be corrected via hyperterminal to the ups at 2400 baud using the apc smart protocol (need to ask apc or google for the two digit hex code that makes up the constant), or by plug in serial "cal-key" dongle offered a few years ago by APC, or by using "APCfix" software from Russia (not authorized by APC).