The scantronic 9454 was installed a few years ago and performed very well. It covers all windows and doors on the ground floor. Recently it suddenly went into 'Tamper' mode and I have been unable to find any local service outfit to repair it. The original firm from whom I bought the system disappeared some time ago. I have removed the batteries and disconnected the mains pending finding someone to carry out a repair.
The 12v battery has lost the ability to hold its charge - normal with old batteries. The 9454 unit trickle charges the battery from mains supply but just breaks the just a few mS every second and checkes the "off charge" volts. If it drops too much it provides tamper warnings.
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