After the computer was repaired, it was immediately prepared to be commissioned as an APCUPSD server. I had just gotten my Tech Room network setup in place and was in the process of getting everything installed and configured on all of the computers in it. It entered service in January of 2018 as an APCUPSD server. It did it's job well and I never had a problem out of it.
On July 4, 2018, I had what I presumed to be a battery failure in the UPS. Not long after that happened, I had a replacement set of batteries in my hands. I connected them up and left it alone. But it wouldn't stay that way for long, because one late September night, after returning home from a football game, I discovered that the UPS was reporting less than 100% battery charge, and I know we hadn't had any power anomalies that night. I left it alone, hoping that it returned to normal overnight. Which it didn't.
Around 3 days after noticing that the battery level was less than 100%, it was reporting critically low battery charge. I decided to have a closer look at the UPS. I eventually came to the conclusion that the UPS itself was faulty. I powered off all load, powered off the UPS, unplugged it from AC power, and pulled the battery disconnect. That was the last time that UPS ever saw electrical power. I salvaged the battery pack and transformer out of it, and the rest was disposed of.
The UPS failed because a high current connection on the transformer failed, disabling the battery charging circuit. The batteries were soon discharged. I still have said transformer and have no plans to get rid of or sell it. The APCUPSD server was decommissioned. It had a hard drive swap done sometime in late 2018 or early 2019 and it lost it's early 2018 installation of Ubuntu Server 16.04 LTS.
In May of 2020, I acquired another APC Smart-UPS 1000, the exact same model of UPS that had previously failed. (APC SUA1000 is the exact model number. It's a 3rd generation APC Smart-UPS with full smart signaling capabilities.) It had it's factory battery pack that was totally useless for all intents and purposes. I swapped it out with the battery pack that I had pulled from the old APC Smart-UPS when it died in September of 2018. Additionally, I pulled out my old APC Smart Signaling Cable (These UPSs need a special serial cable since APC mucked with the serial port on the UPS end. Attempting to use a regular serial cable will result in the UPS shutting itself off when the computer tries to open a connection on the serial port to the UPS, also because APC (ab)used the serial port for it's own special purposes.) and connected it up. I then installed APCUPSD and minicom on the APCUPSD server and began configuring the UPS and APCUSPD. I configured the UPS using it's hidden serial console and a couple of guides to the effect of such. After about a week of configuring and testing everything on all of the Tech Room computers, I finally had a good config. The APCUPSD server has been in 24/7/365 service since and I have no plans to retire it, even though it has what is now a 21 year old Western Digital AC14300R 4.3GB HDD.