Motion Security Sensors

Infrared motion sensor 466282673Motion security sensors are one of the primary types of home security products used today. The most interesting thing about them is perhaps how they work – how does a motion sensor know to react when a person walks by and not when a leaf falls in front of it? What if a cat walks by instead of a human, or what if there’s an earthquake? Using precise detection technology, motion security sensors are able to detect when a human being has crossed their path, which makes these detectors extremely valuable when attached to home security products such as video cameras and outdoor lighting.

PIR Detectors

Although there are many different types of motion sensor technologies, PIR detectors are the most commonly used security sensors in home security systems. And the way they work is rather fascinating. PIR stands for “passive infrared” – passive meaning that they sense when something happens which they did not cause, and infrared referring to what they detect. PIRs are actually able to detect changes in infrared energy wavelengths. As human beings with warm body temperatures, we emit a certain amount of infrared energy from our bodies. The amount of energy we emit can be measured and detected by instruments that are made to do so. With motion sensors, their PIR detection is used to note when there are changes in the wavelengths of infrared energy transmitted in their range of detection. If infrared energy comes into their area, they will pick up on it, and if it changes quickly, they will observe the change and postulate that a human has passed by. Then they will signal something to happen, which is usually a combination of elements including powering on the security device and sending an alert or alarm to the homeowner. Of note is the fact that these security sensors are carefully made to detect an appropriate amount of change – for example, if the sun is shining on a motion sensor light, and the sun begins to set, the change in energy will not elicit a reaction in the motion sensor.

Enabling Their Effectiveness

Being that PIR security sensors need to be able to detect energy wavelengths, they cannot be blocked or they will not be effective. This means that motion sensor security sensors will work only if there are no obstructions such as lawn decorations or furniture in their way to block their detection. It also means that if a person outside of a window is looking in to see if anyone is home, a motion sensor security device placed inside the window will not pick up the movement. Furthermore, PIR sensors shouldn’t be placed too near to heat sources such as ovens or clothing dryers or the heat emitted from them will interfere with the signals that the motion sensors can pick up.

Family Preparing Salad 81754975Application in Security Systems

Motion sensor technology has made security sensors particularly useful for cameras and lighting. When motion has been detected, the camera will power on and begin filming or snap a picture, or the light will switch on to reveal the culprit. And once the device has received the signal, another signal is sent to you in the form of an alert to your smartphone or home security control panel or in the form of an audible alarm to be heard.

When trying to detect and deter unauthorized persons who would enter your home illegally, motion security sensors can be highly useful. And with all the varieties in security devices that enable motion detection, at least one of them should fit with your plans for your home security system.