Security Electronics Circuits Manual

4

Anti-burglary security circuits

The best known and most widely used type of electronic security unit is the so-called ‘burglar alarm’, which is usually designed to detect burglars attempting to break into protected premises while at the same time letting authorized individuals roam freely within those premises and to easily enter or leave their perimeter zones. It is important to understand that normal burglar alarms are last-resort devices that cannot be used on a ‘stand alone’ basis to give good protection against burglary; to give good protection, they must always be used in conjunction with various physical defences/deterrents and with mechanical security devices such as locks, latches, and security windows, and their sensors and sirens ...