Do your UPS units have built in ability to clean up dirty AC power?
I run a 1250 watt pure sine wave inverter with built in transfer switch and charger, tied to a couple 12v 105aH batteries. It has less than 20ms transfer time. My CPU is not affected when power goes out. I haven't done the math, but it should give me enough time to get home and fire up the small generator if power hasn't come back on by then. Will probably last for days if the sump pumps are not running too. Not sexy, but it works.
No power cleaning ability, but I have a whole house surge unit and small surge protectors at every outlet with electronics.
Not sure if the question is being posed to me vs others but this is what's in place as it pertains to
Dirty Power. At a high level no one can change what comes into the home via the POCO so if your utility is known for shitty power - you have shitty power. If you're like me our utility provides clean and reliable power all of the time so there isn't a lot I have to worry about in generalities.
Now . . .
Regardless of how clean the power coming into the home is every home generates its own
Dirty Power. This comes from anything with a motor / compressor like a fridge, freezer, sump, well pump, HVAC, etc. Lots of people focus on the
Act of God lightning events but every day your home is seeing micro sags, lulls, surges, spikes, etc. This is why any form of filtering or AVR must be deployed in a tiered fashion from service entrance, service, panel, inline, and point of use.
Remember an ordinary so called SPD (Surge Protective Device) offers absolutely no protection for a voltage sag (Brown Out). A voltage sag is one of the most dangerous conditions that can happen besides a slowly rising voltage that exceeds 130 VAC. When voltage falls many highly regulated electronics that try to maintain a defined voltage will increase in current draw.
This is why so many things go poof during a brown out event . . .
As stated here and many other places this is why when its possible always purchase devices that support a wide multi voltage operating range. Devices that support 120 ~ 240 VAC will easily sustain a 140 ~ 150 VAC
creeping rise if present. The same is not true for any common electronics that was designed to operate in the 120 VAC region. Not all AVR's are designed or built the same and this comes down to again when does it cut in vs cut out.
Many of the more expansive AVR' / UPS allow the user to fine tune and limit the upper and lower limit. Whereas cheaper ones offer nothing that the electronics wasn't going to do by default!
Seen below I can limit all three ranges within each band and even fine tune within the same.
One of the UPS in its default state getting ready to be fine tuned.
So all of the above only addresses line voltage and doesn't have any relations to other harmonics possibly on the line. This is where different types of filtering come into play whether it be simple resistor network, capacitor, chokes, RLC filtering etc. For those who get really serious or operate in a high risk environment isolation transformers and optical relays (SSR) are used as is in my home in various places.
It goes without saying having the ability to monitor all of these events provides facts and not guess. Here is just a old snippet of power monitoring in my home while everything was getting deployed. It should be noted I programmed the monitor to capture the slightest out of band events which are completely fine in the real world! I did this mainly to see how the micro sag / surges impacted my automated safety programs and wanted to avoid as many false positives.
Everyone likes to see a graph.