Thank you, no issues with electricity I know what to do ;) This ups is planed for my bedroom, and really do not want beeping sounds until i am slipping.
Can be some other small ups .. but must have AVR since sometimes a I have some voltage anomaly ( dont ask why long story ) also short power outages .. for 1 to 2 mins .. not every day but once per month happen ... And yes is nothing which is related to my el. Installation.