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The Beginner’s

Guide to

Motion Sens rs

Introduction

A motion sensor (or motion detector) is the linchpin of your se- curity system, because it’s the main device that stays one step ahead of the burglars. Like something from Mission Impossible, motion sensors may use multiple technologies to detect move- ment in an area, sensing when someone’s in your home. If a sen- sor is tripped, a signal is sent to your security system’s control panel, which connects to your monitoring center, alerting you and the monitoring center that something’s amiss at home. This guide will answer all your questions about motion sensors: the different types, proper placement, and how to use them. !!

Types of Motion Sensors

There are two types of motion sensors: passive sensors and ac- tive sensors. Each uses different technology to detect motion in the designated area. Passive sensors do not emit energy, but read changes in energy in the surrounding area. Active sensors emit one of three kinds of energy to identify motion in the surround- ing area: infrared light, microwave radiation, or sound waves. If you love detailed descriptions and technological language, read our breakdown of the different kinds of motion sensors below: Passive Infrared (PIR): Detects body heat (infrared energy). Pas- sive infrared sensors are the most widely used motion sensors in home security systems. When your system is armed, your motion sensors are activated. Once the sensor warms up, it can detect heat and movement in the surrounding areas, creating a protec- tive “grid.” If a moving object blocks too many grid zones and the infrared energy levels change rapidly, the sensors are tripped. MicroWave (MW): Sends out microwave pulses and measures the reflection off a moving object. They cover a larger area than infrared sensors, but they are vulnerable to electrical interfer- ence and are more expensive. ! !!

Dual Technology Motion Sensors: Motion sensors can have combined features in an attempt to reduce false alarms. For ex- ample, a passive infrared (PIR) sensor could be combined with a microwave sensor. Since each operates in different areas of the spectrum, and one is passive and one is active, Dual Technology motion sensors are not as likely as other types to cause false alarms, because in order for the alarm to be triggered, both sen- sors have to be tripped. However, this does not mean that they never cause false alarms. Area Reflective Type: Emits infrared rays from an LED. Using the reflection of those rays, the sensor measures the distance to the person or object and detects if the object is within the desig- nated area. Ultrasonic: Sends out pulses of ultrasonic waves and measures the reflection off a moving object. Vibration: Detects vibration. These can be purchased or easily made at home. A homemade vibration sensor uses a small mass on a lever, which is activated by a switch to an alarm when it vi- brates. Homemade motion sensors can work, but they can also be unreliable. !!

Double-edged Motion Sensors

Despite their name, motion sensors have many uses besides just sensing motion. Motion sensors are often paired with other types of technology for a dual function that leads to all kinds of cool uses. Case in point: if you have a motion sensor paired with a security camera or a lighting fixture, you can program them to turn on only when motion is detected. Here are some examples of how motion sensors can be used with other technology for optimal security: Motion-sensor lights: Motion-sensor lights are perfect for the outside of your home. When it’s dark and someone’s lurking out- side your home, motion-sensor lights will automatically come on. This means you save money on electricity because you don’t have to keep your lights on all night if you don’t want to. Addi- tionally, motion-sensor lights can be used inside your home, too. You can program your security system so that lights will come on when motion is detected to make it look like someone’s home, to scare off intruders, or to brighten up a room to snag clear foot- age of an intruder on camera. Motion-sensor cameras: You can set up your motion-sensor camera to only record when motion is detected, so you only have important events recorded and you don’t have to sift through hours of unwanted footage. Many times, you can also set up your camera so that you receive an instant text or email alert if motion is detected, and you can view camera footage remotely from your smartphone or other web-enabled device. Motion-sensor alerts: Motion sensors can be used for more than catching intruders. If you have monitoring with instant text or email alerts, you can set up motion sensors on medicine cabi- nets, liquor cabinets, gun safes, or other restricted areas, so if anyone tries to open a restricted area, you’ll get a text or email alert. You’ll never have to worry if your kids are getting into off- limits stuff without your knowledge.

Motion-sensor response: You can set up various responses when motion is detected—the sky’s the limit. Some people buy “fake dog” sensors, so that if motion is detected near a back door or garage, a recorded dog bark will start playing, hopefully scaring off intruders. If you’re having motion sensors professionally installed, make sure to talk to your installer about equipment options for dual- technology sensors. If you’re installing yourself, consider all your options before ordering your equipment, and read our next sec- tion on how to set up motion sensors for best results. !!

4. Motion sensors work best when the intruder walks parallel to the sensor, not toward it. For example, in a hallway you tend to walk parallel to the walls, not directly toward them. Find walls that an intruder would walk alongside, like a hall- way or narrow pathway that leads to a room. If you have any questions while installing your motion sensors and you got your equipment from a security company, you can always call customer service. Most DIY installation security com- panies also walk you through a process to test your equipment.

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Conclusion

Motion sensors have a wide variety of uses, and it’s good to know your options before deciding on which ones to use in your home. For more information on security systems or if you have any fur- ther questions about motion sensors, visit us at www.safewise. com or email us at info@safewise.com. Good luck with your mo- tion sensor search!

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