If you are stuck for decent free UPS monitor and graceful shutdown software for Windows 10, or a bit put out by the lack of software or enormous Java apps provided by many UPS manufacturers, you can’t do much better than these two apps.
It does depend on your UPS as to whether these apps will work for you, but they are very small and work fine on my SYNDOME/Mustek Cypress semiconductor USB-Serial UPS running on Windows 10 64 bit.
Winmust
http://winmust.sourceforge.net
Tiny download but nice status display and has shut down options. Very simple program with tiny memory footprint and minimal performance impact.
UPS Assistant
http://foxylab.com/UPSAssistant.php?en
Another tiny download. Does not look as nice but has SMTP/HTTP and LAN network message notifications as well as shutdown options. All the usual information is there. An obvious choice if power event notifications are what your looking for.
Let me know in the comments if you found any other small free UPS monitoring software and I’ll add them to the list. Also let me know what other makes/models of UPS these programs work on for you.