I don’t know with your system, Fred, but I’m guessing the alarm is on the VEHICLE circuit, the normal installation, and not the habitation (Electroblok) circuit. Alarms are normally chosen and fitted by the first owner, and can be of many different types so it’s not always clear how it’s been installed. It’s easy to test which battery circuit though, in order to be certain – disconnect the vehicle battery and if the alarm still works, it’s off the habitation (unless the alarm has it’s own ‘back-up’ battery? In which case test with a voltmeter) or ask a local friendly alarm installer.
Barry