alan67

Possibly the ultimate necropost .... That replacement battery lasted 11 years, replacing it again now!

New battery is in and system now works as expected with mains power removed. However, I will remove the mains power for half a day and check the charging current on reconnection once the battery is drained a bit Al.

Thanks for the answers. Just had a look - Battery is a Yuasa NP2.8-12 and the off-load/off-charge voltage is only 11.65 New battery ordered - Hopefully it is just the battery and not the charging circuit! Al.

Had a power cut on Saturday and the outside bell box came on (doesn't usually during a power cut). The panel was dead - Couldn't enter the code or reset to kill the alarm. Luckily the power came back before the neighbours got really annoyed I'm guessing the the backup battery has died; No power to bell box causing it to trigger, dead panel. The alarm is at least 7 years old, so I guess the battery has probably had it. Before I dig the manual out (put away in a safe place 7 years ago, hope I can find it!) or take the panel apart, does my diagnosis sound reasonable, and does anyone know a model number or part number for the battery to save me taking it apart twice to find the part number and then to fit it once I've got the battery? Thanks, Al.