Burglar Alarms and Home Security

Home security systems are basically built around burglar alarm circuits. Understanding how these operate would go a long way in trouble-shooting malfunctions or installing burglar alarm systems in your home. 

Burglar alarm circuits are essentially electrical circuits that are built into an entry way of a house. When a conduit is provided to connect the two opposite charges, the electricity starts to flow in burglar alarm circuits. Simply stated, a circuit can be opened or closed by flicking a switch, which turns on or off electrical appliances. In like manner, when the electromagnetic contacts of a burglar alarm in a window are tripped off, electricity flows into the device and a siren sounds off.

The two general categories of burglar alarm circuits are the closed and open circuit systems. In a closed circuit system installed on a door, for instance, there is contact between the two wires so the electricity is flows continuously through the security device. If the door is opened, the electricity is cut off triggering the alarm. In an open circuit system, electricity starts to flow through the security device the moment the door is opened. An intruder can easily disarm open type burglar alarm circuits by cutting the connecting wires that is why closed circuit burglar alarms are most commonly preferred by homeowners.

Burglar alarm circuits can be installed into an entry way in many ways. One of the most common is a simple electromagnetic device that is switched on when a window or a door where its contacts are positioned is opened. Another common switch is simply a button that is placed between the window pane and window jamb. Once the window or door is opened the button is released and the siren goes off. The inherent weakness of these switches is that the intruder can turn off the alarm by closing the window or door where the switches are positioned.

Modern burglar alarm circuits have control boxes that monitor electrical circuits installed at different key entry points in a house. The moment there is a change in any of the burglar alarm circuits, it triggers the alarm and will not stop until the homeowner keys-in on the key pad a pre-determined security code. These control boxes are often placed in a concealed place like a cupboard so that the intruder will not find and destroy it. State of the art burglar alarm circuits use ultra thin foil wires that are fixed on window panes to detect glass breakage, inconspicuous triggers beneath carpeting and other sophisticated triggers like infra-red sensors, motion detectors and volumetric sensors that detect changes in air pressure due to the opening or closing of windows and doors.