Burglar Alarm Sounds When Power Cut

We all hear the chorus of alarms if the power in our area is cut off even briefly.

Burglar alarm sounds when power cut.

This means the back up battery which is meant to keep the alarm running is unable to keep the alarm system running therefore setting the alarm off. Therefore when the mains is removed the main control panel battery can t keep the system running so the external sounder starts ringing to inform you there s a problem. The backup battery maintains power to the alarm panel sensors and sounder in the event of a power cut or when an intruder cuts the mains power to the panel. This is a security feature to prevent burgulars simply cutting power to an alarm to stop it.

For this reason all modern alarm systems have a battery backup designed to power the system for 10 24 hours depending on the complexity of the system and the condition of the battery. An alarm panel is usually provided with backup power by a 12 volt lead acid battery. No is the only answer to this question. When mains power is cut to an alarm most alarms sound powered by their own internal rechargeable batteries.

Batteries have a lifespan of approximately 5 years and if it is changed during these intervals then your system should not cause any undue false alarms during a loss of power. However if your alarm does go off during a power cut there may be a fault with it. It s also quite possible that the 20 minute limit is disabled with a power cut as well. Of course the alarm can t tell the reason for the mains supply being interupted hence why it sounds when there is an unintentional power cut.

All professionally installed and maintained alarm systems must have a fully operational battery back up system that should keep the system operational for at least 12 hours and it should be checked by your maintainer each year. In less expensive systems nickel metal hydride nimh aa cells may be used. When all power is cut including power to alarm systems the number is even higher. So what can happen if you do not change or renew the battery.

Alarms also commonly go off when the power is interrupted presumably because it thinks that a burglar has cut the power to try and break in. 98 of the time an alarm rings during a power cut is because this battery is dead.