Synology uses a customized version of Network UPS Tools (NUT) for controlling and sharing its connected UPS.
In Control Panel | Hardware & Power | UPS, DSM displays minimal information about the connected UPS. Synology only provides one NUT tool – upsc – but this tool can give you detailed information about the UPS. If you simply want basic info from your Synology, SSH into it and run the upsc command (to see the full options for upsc refer to the upsc man page):
$ upsc ups@localhost
The name of the Synology UPS is ‘ups’ and the default location is localhost.
On the Control Panel UPS screen there is an option to ‘Enable network UPS server’ and configure ‘Permitted Diskstation Devices’. This does not apply to only Diskstations. Any device running upsmon can also talk to the Synology’s NUT Server. This means you could connect your UPS and its USB cable to your Synology and connect other computers to the UPS power receptacles, assuming the UPS has the required capacity, and those other computers could shutdown in an orderly fashion in the event of a power failure.
Unfortunately, Synology chose not to include the other NUT tools that can read and write to the UPS – upscmd & upsrw. So if you need to change the non-volatile parameters of your UPS, you will need to plug the UPS comm cable into another machine that provides these tools.