Week : 5

Title : Concept of motion detector for security system

Objective : To know how infrared motion detector components work

Content / Procedure : 

 

Figure 1 : Infrared Motion Detectors

Result / Analysis :

Figure 1 above show the operation of an infrared motion detector for security system. In the system each sensor consists of two housings.One housing contains an infrared emitting diode and an infrared sensitive phototransistor as infrared detector. The other housing contains an infrared reflector to reflect the infrared signal.When positioned in front of an entrance to a protected area, the two housing establish an invisible beam as shown in figure 2 below:

Figure 2 : The concept of infrared motion detector for security system

Conclusion :

A person who enters the area will interrupts the beam causing an alarm to be trigerred. For this type of motion detector use the basic concept of the infrared motion detector.An interruption in the signal modulated pulsating beam transmit by an infrared diode while receive by an infared detector that will set 'on' or 'off ' the alarm of the security system