BK500 remains 'on battery'

[Anonymous user]

my old BK500MI (serial NB9828051536) always worked fine...but yesterday i came back home and it is beeping without any blackout occurring.
the power plug is in , the power socket is ok, the overload protector isn't popped , powering it off and then on: it restarts its beep-beep.
Battery measured about 12.2volts on a DVM then I replaced with a newer one from a CS350 (same capacity 7.2 Ah)
The beep-beep doesn't stop. It seems the ups can't go online but works ok on-battery and in the "surge protection only" outlet I measure 220VAC (right value for italy)

maybe some inside AC fuse blown?

Message was edited by: ziomarco

Message was edited by: ziomarco

[BillP]

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[Anonymous user · Accepted solution]

Hello to all the folks in the forum.

I think mr. largebattery is a spammer...let's go talking about my ups.

Today I opened the case and found the sitation shown in the attach file.
The varistor is clearly burned out.
Have I some hope of repair my ups by replacement of the varistor?

Thanks in advance for help.

ziomarco