We have had a couple of power cuts recently which have upset my alarm ,an optima xl. First the panel would not re-set, fixed that by replacing links etc as per manual, during last power cut sounder started going off at soon as power went off.Are these events pointing towards a battery fault?
It needs a new battery in the panel George. Dependant on the size of the system you would expect it to stay up for at least a few hours without mains. Should cost you about £10 from an electrical wholesaler.
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