Hello, I dont know if this is the right place to ask for UPS troubles. Sorry, in advance.

My UPS lights all three of em keeps flickering when I turn it on and it gives a sound which always could be heard once when you turn it on or turn it off. The flickering started after a 15 mins blackout and when I came back to turn it on it became like this. The flickering is there and there is no power. My UPS version is IDEAL 5312A 1200VA.