Motion Detectors

Motion Detectors are devices that a homeowner or business owner uses to be alerted when someone is on their property or in their building. Motion detectors are used as part of a security home or commercial security system, and this website will explain how the work and discuss the different types.

Motion Detectors - Overview - A motion detector is a piece of equipment that can be used alone or as part of a complete business or home security system. Infrared detectors, passive infrared detectors and outdoor motion detectors are intended to sense any movement that occurs and notify the owner of the location when motion is detected. Some motion sensors are a small part of a more complex security system, while others are simple and basic, giving the owner of the location and audible sound during motion detection.

When motion detectors are a part of a security system they enhance the overall systems performance tenfold. While a standard security system usually offers the user a control pad, cameras, video surveillance and the like, motion detectors can be used to determine if someone has entered the location or if someone is outside wandering the surrounding areas outside of the location being monitored. Motion detectors come in several different varieties, some more sensitive than others and they can be set up to make a noise to alert the owner of the location or to silently trigger other monitoring tools to begin working. Motion detectors can be used to turn on lights, to start recording when some one sets the motion detector off and some may automatically trigger the security system to call the police in the event that there is an intruder on the location being monitored.

Many people that have security systems in their homes rely on the protection offered by the use of motion detectors. In contrast, there are some complaints with the sensitivity of some motion detectors: the primary complaint being that some motion detectors are set off with far too much ease. There have been however, advances in technology that have allowed for major improvements in the area of motion detection sensitivity: motion detectors now have a special sensitivity that does not get set off by low level motion, motion typically caused by animals roaming around on the location outside or in the home.

Advantages - A motion detector is a piece of equipment that is used in a variety of security and surveillance systems. Motion detection is precisely as the term defines: the act of detecting motion in an area being monitored by an electronic surveillance device. Motion detectors are an important part of a complete surveillance system: while one can feel secure from having cameras, video recorders, and glass breaking alarms, motion detectors can alert the proper authorities about the location of an intruder and can even stop some crimes in progress. Motion detectors can signal alarms that will frighten away intruders or they can silently set other protective measures into action.

Motion detectors can be set up outside one's home or business to trigger the lights to come on when an intrusion is occurring. Thieves love the cover of darkness and when motion detectors pick up the movement of a body, the lights will shine on the intruder, causing them to flee. In fact, motion detectors have put an end to many crimes in progress. Business owners have been using motion detectors since they have been on the market to protect their business and assets and more and more homeowners are taking advantage of the protection offered by such devices.

Motion detectors are an essential part of the layered security system. Some home owners may rely on motion detectors alone, particularly for outside purposes. Outdoor motion detectors can turn the outdoor lights on when motion is detected in the front or back yard and can alert homeowners when someone has trespassed onto their property or when someone is approaching the home. Nevertheless, motion detectors are most effective when used in conjunction with other surveillance equipment.

Types - Motion detectors can be divided into two specific groupings: space motion detectors and perimeter motion detectors. Space motion detectors are typically used inside the location and used to monitor specific areas or rooms. Common locations for space motion detectors are bedrooms, hallways, lobbies, living rooms, dining rooms, kitchens and the like. They can also be used inside the garage to detect intrusion. There are a variety of different space motion detectors but the two main detectors are passive infrared motion detectors and microwave motion detectors.

In contrast, perimeter motion detectors are used for outdoor use: to monitor the front and back yard, driveway or any location surrounding the site under security surveillance. Perimeter motion detectors are often placed on windows, entry ways, and walls. There are a number of different perimeter motion detectors that vary in size, shape, type, and functionality.

The most popular types of motion detectors are the microwave motion detectors and the passive infrared motion detectors. Microwave detectors rely on the use of radio ways and infrared relies on the use of invisible light for detection. Meanwhile, there are other types of motion detectors that are used, but less frequently. Ultrasonic motion detectors rely on using sound and sound disturbances to detect motion and video motion detectors rely on the equipment's ability to detect changes in ambient lighting. Regardless of the motion detector selected, motion detection works far better if used in conjunction with a complete surveillance system: cameras, window contacts, door contacts, and pressure mats ensure that a location is completely secured.

Installation - Motion detectors can be installed by the consumer but it is recommended that for more sophisticated surveillance needs that the detectors are installed by a professional in security measures. The sensitivity of motion detectors is affected by the way the equipment is installed: the detector must be positioned correctly in order for the equipment to function correctly. Individuals that are unfamiliar with motion detection installation should then rely on the skills of someone that understands the intricacies of such equipment.

Installation of motion detection equipment is usually in areas that are hidden or semi-hidden. Along floor boards, along the borders of walls, near windows, above the front or back doors of a location, and room corners are common areas where motion detectors are placed. The motion detector will have to be place in an area where it will cover the most space possible: sometime a corner gives the best angle, offering a pick up of the entire room. When it comes to ultrasonic equipment, placement isn't as important as in the installation of passive infrared technology-this is because a disruption in sound is easier to pick up and infrared technology counts on the trespasser entering the "vision field" of the infrared motion detector so that changes in heat can be detected. In the same manner, video motion detectors also rely on a limited field of vision: the changes in light in an area are what is detected and the video can only cover so much area. Unfortunately, video and passive infrared will not pick up changes outside the "field of vision": this limits the ability of the technology. However, if the technology is used in conjunction with other surveillance techniques, business and homeowners can ensure maximum security protection at all times.

Alternative Equipment - Some surveillance equipment is often confused with motion detection. For instance, consumers often confuse the use of window contacts with motion detection. Window contacts are not necessarily motion detectors as much as they are a broken circuit detector. While it may seem that window contacts alert individuals to the motions of an intruder by signaling an alarm when the window is opened, the device is not detecting the motion of the window opening. Rather, window contacts are closed circuits that once opened, signal an alarm: the action of opening a window is what breaks the circuit. While window contacts are a nice supplement to home security options, it is not considered a motion detector device.

Similarly, door contacts work in the same manner. A closed circuit is created when the door is shut. When the alarm is set it will be triggered if the circuit is broken. Again, while it may seem that the motion of the door is triggering the alarm, in actuality, it is the breaking of the closed circuit that causes other security measures to fall into place. Some contact switches are magnetic, consists of a magnet and a switch within a small, enclosed plastic box, and they are relatively easy to install.

Glass breaking sensors are also confused with motion detectors. While consumers may first believe that the motion of broken glass falling to the floor is what triggers the alarm, in truth glass breaking devices are equipment that detects broken glass via sound. It is true that the shut thrust of broken glass may actually set off some motion detectors, but special equipment that interprets the sound of broken glass is what detects when a window is broken.

Microwave Motion Detectors - Microwave space motion detectors: these motion detectors are incredibly sensitive because they send out radio waves that, in turn, fill a room. Any disruption in the waves and the motion detector is set into action, whatever the pre-selected action may be. What is particularly nice about the microwave space motion detectors is that they can be well hidden: microwave space motion detectors can be situated behind a wall or any other object and remain unseen by intruders. How is this so? Radio waves can easily pass through solid objects, making it completely possible for the motion detector to work without having a clear line to the room it is monitoring. Consumers must bear in mind however, that microwave space motion detectors also have some minor difficulties associated with them, primarily that setting them up for the first time can be a little more difficult than installing other motion detectors; this is because radio waves can pass through objects, including walls, and the installer will have to situate the motion detector so that it only monitors specific areas. If the motion detector is not set properly, it may signal an intrusion when one is not occurring.

Passive Infrared Motion Detectors - Passive infrared motion detectors: These motion detectors were specifically designed to eliminate the previous problem with motion detectors-the problem of false signaling. Often times, the less expensive varieties of motion detectors created havoc for the site owner using surveillance: motion detectors would detect motion and set of alarms for something as small as a breeze or an animal outside the location. The passive infrared motion detectors are the most popular of motion systems because their sensitivity has been stabilized. Instead of detecting motion alone, passive infrared motion detectors also note temperature fluctuations in the are being monitored and it will pick up on the body heat that a human body gives off. To understand how a passive infrared motion detector works imagine the following:

A passive infrared motion detector has been installed and it is ready to monitor a site. The average room temperature of the area being monitored is 68 degrees Fahrenheit. Now imagine that an intruder enters the area: humans have a body temperature of 98.6 degrees Fahrenheit. The passive infrared motion detector will pick up on the sudden increase in temperature and in doing so will signal the alarm or other devices it is working with. What's fantastic about passive infrared motion detectors is that they are set up to disregard small changes in the room's temperature and to only regard erratic or sudden changes. Plus, passive infrared motion detectors can be specifically set to distinguish between horizontal and vertical shapes and they can thereby eliminate the possibility that an animal like a household pet will set off the motion detector.

The down side to having passive infrared motion detectors is that their range is small-- passive infrared motion detectors focus on small areas only and consumers may have to invest more money to protect are large area. In contrast, the consumer can also discuss with a dealer the different types of motion sensors lenses and their effectiveness when it comes to using passive infrared motion detectors. Some lenses offer better overall coverage of an area. The range in which a passive infrared motion detector functions in between 25 to 35 feet, depending upon the equipment purchased and how it is installed at the location.

More on Passive Infrared

Passive infrared is sometimes referred to as pet immune technology? Why such a reference? Basically, many motion detector systems created a problem for homeowners that owned small animals. Motion detectors were being set off at all hours of the day or night because "fluffy" had inadvertently strolled into a room or area being monitored. Passive infrared technology eliminated such difficulty, by increasing the sensitivity of the motion detector, while decreasing the "miscommunications" that were cropping up.

Ultrasonic Motion Detection - While considerably older technology, there are still some surveillance systems that incorporate the use of ultrasonic motion detection. What is ultrasonic motion detection? Ultrasonic motion detection is the use of sound frequency in motion detection. Sounds that cannot normally be heard are transmitted into an area: when motion occurs, it disturbs the frequency of the sound waves and triggers the alarm. Bear in mind however, that this technology is not used as much as microwave or passive infrared because of the system's extreme level of sensitivity: while small movements will not set off an ultrasonic motion detector, intense drafts might.

Video Motion Detection - While ultrasonic motion detection focuses on changes in sound, video motion detection focuses on changes in the field of the camera's vision, particularly changes in light. The down side to video motion detection is that motion cannot be detected in darkness and some light will have to be present in order for the system to work. Light changes are assessed in the changes of pixilation in a computerized image of the site that is picked up by a video recorder. The pixels are then assessed for changes in their light and dark aspects. Noticeable changes then trigger an alarm. Video motion detection and ultrasound motion detection are still present on the surveillance equipment market, but overall passive infrared technology is taking the lead in sales of motion detection equipment. Remember, video motion and passive infrared have limited fields-and they should be used as a supplement to a complete security system.