You've inherited a good system in the 500r. If the low battery light is on with a zone light you need to change the battery in that zone - usually AA in PIRs and AAA in door contacts. If the low battery light is on on its own you will need to replace the sealed lead acid battery in the control panel usually a 2.1Ah which is charged continuously by the panel.
If you haven't got a user code you will need an engineer to recode it for you.
Alarm Engineer Bristol
November 2007
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