Security systems come in a lot of different models with varied features. In addition to choosing between a wired or wireless system there are varying degrees of motion sensor systems as well. If you want to monitor the exterior of your home it is best to use a motion detector alarm system. These systems are triggered when they sense activity or movement. Motion detectors are used in areas of our everyday life that most of us don’t generally see.
The electronic doors on a store that open and close when we enter or exit use a motion detector device. Generally these are infrared detectors. The detector is usually a small box unit above the door itself which emits small bursts of microwaves or ultrasound waves. When the waves make contact with an object such as a person, they are then reflected back to the door as a disturbance which causes the door to open.
When infrared signals are used in a security system alarm, the same principles apply. The unit emits a wave which when disrupted by the movement of something in its path triggers an alarm to sound. Security alarm systems can also be photo-sensor alarms. These types of alarms are very common in store security systems. This is where a laser or beam of light is the sensor for the alarm. When something interferes with the beam, as when you cross through a doorway, it triggers the alarm to sound. When used in high security systems such as in a museum where there are priceless items, several beams of light are used to detect motion.
Another type of a motion detector alarm is the passive infrared alarm. Instead of emitting its own waves of infrared energy the alarm is constructed to pick up on the infrared energy of objects that pass by it. Since people emit infrared energy in their body heat, the sensor can pick up when a person passes by and then signals an alarm to sound. The drawback to this type of system is the amount of infrared energy needed before the sensor picks up the activity. Because the level usually needs to be rather high there is potential for getting past the alarm.
Many of the motion detector security systems used in homes will be connected to a master control box. The master controller is usually programmed with a delay timer for signaling the alarms. This delay time gives the homeowner a chance to override the signal if it was triggered by mistake. These master control boxes generally have a key code that needs to be entered before being able to override the alarm. This prevents unauthorized people from being able to shut off the alarm system. If you have valuables in your home you would benefit from using a motion sensor alarm of some type.