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Although invisible to the human eye, the magnitude of infrared energy can be quantified by a pyroelectric sensor. This sensor is placed behind an infrared-transparent cover, so that it may monitor objects with varying infrared energy. Similarly to the way an electric charge is created when visible light strikes a solar cell, these sensors generate a small charge when subjected to infrared energy. As an object with a more intense infrared energy, such as a person, is detected by the sensor, it overlaps a section on the chip that had previously been subjected to some much cooler object, such as a wall in the background. The pyroelectric sensor is connected to an energized relay, which acts as a "switch," completing the load circuit. As this warmer, or more energized object, moves along the lens of the sensor, the relay becomes de-energized, the contacts of the relay become operational, activating the detection switch of the control panel. Similarly, if an object colder than the background wall is presented into the field of view of the sensor, the difference in infrared energy will still cause the relay to be de-energized, activating the detection switch.<ref> Machine Design (2008), ''Sensor Sense: Passive Infrared Motion Sensors'',http://machinedesign.com/article/sensor-sense-passive-infrared-motion-sensors-0710</ref> <ref> Wikipedia, ''Passive Infrared Sensor'',http://en.wikipedia.org/wiki/Passive_infrared_sensor#PIR-based_motion_detector</ref>
 
Although invisible to the human eye, the magnitude of infrared energy can be quantified by a pyroelectric sensor. This sensor is placed behind an infrared-transparent cover, so that it may monitor objects with varying infrared energy. Similarly to the way an electric charge is created when visible light strikes a solar cell, these sensors generate a small charge when subjected to infrared energy. As an object with a more intense infrared energy, such as a person, is detected by the sensor, it overlaps a section on the chip that had previously been subjected to some much cooler object, such as a wall in the background. The pyroelectric sensor is connected to an energized relay, which acts as a "switch," completing the load circuit. As this warmer, or more energized object, moves along the lens of the sensor, the relay becomes de-energized, the contacts of the relay become operational, activating the detection switch of the control panel. Similarly, if an object colder than the background wall is presented into the field of view of the sensor, the difference in infrared energy will still cause the relay to be de-energized, activating the detection switch.<ref> Machine Design (2008), ''Sensor Sense: Passive Infrared Motion Sensors'',http://machinedesign.com/article/sensor-sense-passive-infrared-motion-sensors-0710</ref> <ref> Wikipedia, ''Passive Infrared Sensor'',http://en.wikipedia.org/wiki/Passive_infrared_sensor#PIR-based_motion_detector</ref>
 
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'''<b>False Activation Prevention</b>'''
 
'''<b>False Activation Prevention</b>'''
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