| A PIR sensor, if attached to an alarm, can detect | | | | You can think of the PIR sensor as an infrared |
| intruders. This is because changes in temperature can | | | | camera that remembers how much infrared energy is |
| be picked up by the sensor, which can happen due to | | | | on its surface. When power is applied to the sensor, |
| movement in the sensor's field of observation. | | | | the electronics will control a set of circuits that are |
| Security is a big issue nowadays, whether you are | | | | connected to and can activate the control panel of a |
| talking about home or business. One way to ensure | | | | security alarm. When a person enters the PIR sensor's |
| security is to install alarms, and one kind of alarm is the | | | | monitored area, the sensor picks up the infrared |
| PIR Sensor Alarm, which is based on the technology | | | | energy that the person's body emits. This infrared |
| of the Passive InfraRed sensor. The infrared sensor is | | | | energy is then focused by a segment of mirror or a |
| an electronic tool that measures the degree of infrared | | | | Fresnel lens. This detected energy overlaps a certain |
| light radiated by objects that pass through or that are | | | | part of the sensor chip that was measuring a cooler |
| picked up by the sensor. Such sensors are used to | | | | part of an area that the PIR is protecting. As the |
| construct motion detectors, which are attached to | | | | person moves, the hot spot on the sensor chip also |
| alarms. | | | | moves, which can activate the alarm through input that |
| This divice will detect movement through changes in | | | | is interpreted as detection. |
| temperature. For instance, if a human passes in front | | | | In other words, differences in temperature can call the |
| of a source of infrared radiation that is of a different | | | | alarm up. This product can be overrun with an intruder |
| temperature, say a wall, display case, or safe, then the | | | | holding a thermal shield that would make him or her |
| sensor will detect the change in temperature and | | | | have the same radiation and temperature as the |
| activate an alarm. This is because all objects emit | | | | surrounding area. This is very difficult to achieve, |
| black body radiation; infrared radiation may be invisible | | | | however, so a PIR sensor can be useful in protecting |
| to human sight, but electronic devices such as the PIR | | | | houses, businesses, and other establishments that |
| sensor are built for detecting this radiation. While some | | | | need security from intruders. For more information on |
| infrared sensors will emit infrared light beams, a | | | | the best PIR sensor for your home or business, talk to |
| passive infrared sensor will simply accept and detect | | | | your local security retailer. |
| incoming radiation. | | | | |