Hey Wayne,
if you want to run a CNC machine during a power outage, it’s not a electronic UPS that you would use, but a engine-generator. Usually the power of a CNC machine is much too high and a UPS to match this consumption would be way too expensive.
How long is a “typical Florida power blip”? If you really have power outages in your country, question is if you should own an engine-generator anyway. Just think of your frozen food.
I’ve only had one lengthy power cut in the last fifteen years since I live where I live today. It was in the newspaper: A European herring gull had been sitting in the power station and when it took off, its wingspan of up to 60 inches short-circuited two high-voltage lines and was literally fried. I have UPS for my IT but the CNC machine would not have been able to be supplied during that power outage.
And even if you buy a UPS that will be strong enough to power your CNC machine, question is will running your program take longer than your UPS battery power will last.
But the question is if you need some reserve power at all. There are some small UPS Raspberry Pi add-ons like this one or this one that just power the Raspberry Pi with a LiIon rechargeable battery and you could wire a circuit that will sense if main power fails and triggers a controlled emergency stop before the battery power is gone. A bit breakage is difficult to prevent anyway in case of power loss. I think for cases of power outage I would make sure that the program is stopped in a controlled way, and then make sure you can restart it when the power is back.
You can restart an interrupted g-code program if you find the offsets in the buildbotics-derived Onefinity Controller’s logfile and enter them manually after a reboot, and then either restart the program from the beginning, or edit it so that the correct modal commands are set and it continues at a certain point. For positioning repeatability and accuracy after a power outage (or after a normal machine shutdown), you would benefit of retrofitting limit sensors to your Original/X-50/PRO machine, as the stock stall homing is not as accurate as you may need.