[ hemigreg ]buy a used commercial UPS for 800 and have better power quality than any "regen" unit cause thats what they are without the battery.
https://www.ebay.com/itm/APC-Smart-UPS-XL-3000VA-RM-5U-SUA3000XL-New-Batteries-1Yr-Wrnty-FreeShip/11...''
I presume you're using the filter provided by the UPS, is that correct?
If so, why not just buy a power filter?
That is, my understanding is that the UPS generates AC from DC if/when: (1) there's a loss of power (from the wall) (2) there's a battery in the unit. Otherwise, the UPS simply filters the AC coming from the wall and keeps the batteries charged.
So, no battery equals no DC, hence no generation of AC from the UPS.
Is that not correct?