Perhaps because it does not SA with the mains off and the panel battery dissed.
Did you read the question?
acorn
December 2009
It really depends on the voltage, what type of bell box you have etc, Why would you want to replace it any way, the SAB as its known is an insurance requirement on maintained systems, im actually curious if you do mean this battery or the stand-by battery.
Regards
Nick 07842 480037
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