I have a major problem with my rack mountable APC SmartUPS 1400. It's a bit old (at lease 4 years). I'm trying to fix the problem for the last couple of weeks but I had no luck with it. Accorting to apcupsd's apctest the input voltage seems to be over 260VAC even though my V-meter shows 219V so it's on battery power constantly. It even shows the wrong battery voltage (about 50V instead od the correct 24V as it has two dual 12V 7,2Ah sealed accus).

That could be wrong? Can it be fixed?

I'm attaching apctest output of a working ups and the non-working one:
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