Wireless alarms today form the basis of security systems in the private sector. They are advantageous both in their communication capabilities and in their simplified technical organization. In particular, the GSM motion sensor forms the basis of this type of household kits. It allows you to timely record the presence of an unauthorized person in the served area, quickly sending alarming information to the target address.
What is a motion sensor?
As a standard, it is a small device with electronic filling in a compact housing. The device can perform both the function of a detector as part of an alarm system and act as an independent means of recording the presence of foreign objects. In the second case, the device has a wider functionality and its own communication system. As for the functional support, a GSM alarm system with a motion sensor usually provides for the possibility of instant messaging through a mobile operator, including using MMS / SMS services.
Wired infrastructure can also be used for energy supply, but this solution is becoming less common, since the emphasis is on maximum secrecy and autonomy. Therefore, as batteries use their own batteries or battery. The same applies to communications, which is provided either by a GSM module or by radio channels operating at a short distance within a private home ownership.
The principle of operation of the device
The main task of the sensor is to perform the function of a sensor of physical activity. In this case, it consists in determining the presence factor in the served area. The principle of operation of the sensing element depends on the type of device, but in each case, an instant notification via one of the communication channels that are pre-configured is assumed. So, an autonomous GSM motion sensor without any wires detects the presence factor, which is immediately reported to the owner, for example, via SMS and simultaneously sends a signal to the security point (if this is possible). Also, depending on the selected work configuration and configuration, the sensor can automatically activate the function of the local siren - this will also be a reaction to the recorded fact of detection of an unauthorized person in the house.
Device views
The following types of motion sensors with an integrated GSM module are most popular today:
- Infrared The principle of operation of this sensitive element is based on fixing changes in the thermal field. This is how pyroelectric sensors provided by Fresnel lenses or active detectors work.
- Ultrasonic In this design, the GSM motion sensor responds to acoustic radio waves reflected from moving objects in the control zone. The device itself can generate ultrasonic vibrations, as well as record the slightest changes in a given ultrasound spectrum. It is important to note that such devices are often sensitive to external factors affecting the thermal environment. That is, they incorrectly perceive signals near operating climatic equipment.
- Microwave The operation of devices with microwave sensitive elements is based on the Doppler effect. The sensor operates on the principle of generating radio waves, from which the interference caused by movable objects is reflected. A special sensor detects vibrations of waves, sending alarm signals at certain frequencies.
- Combined. Each of the above sensors is good in its own way, but also has its own unique disadvantages. Combined GSM motion sensors, in turn, combine the best functional properties of the main detectors, increasing the accuracy of the alarm. The disadvantages of such devices include large dimensions and high cost.
Key Features
It is recommended to evaluate the working qualities of the sensors and the possibilities of their detection by the following parameters:
- Action area. The radius of the coating determines at what distance, in principle, the device can detect movement. Home models, for example, operate in the range of 5-7 m, and a street GSM motion sensor covers up to 15-20 m.
- GSM network parameters. The standard set of frequencies is 900/1800/1900 MHz.
- Viewing angle. It also determines the coverage area, but already vertically. In the simplest models, the angle of the sensor is from 90 to 110 °, but more and more often you can find rotational modifications with a detection zone of 360 °.
- Nutrition. Again, stand-alone devices are supplied with battery cells that hold a charge from several days to a week. But there are network sensors that work from a single-phase 220 V.
- Temperature in the environment of operation. Depends on the purpose of the device - for outdoor or home installation. Universal models can be used in the mode from -25 to 65 °.
What else to consider in choosing a device?
The presence of additional functionality is extremely important for modern alarm systems. On the market you can find complex devices that also include sensors for temperature, smoke and gas leaks. Such a set of sensors will allow counting on the prevention of threats not only of a criminal, but also of a domestic nature. Manufacturers also provide cameras with GSM motion sensors in the security kits, the materials of which are sent in messages, allowing visual monitoring at times of alarm. Particular attention is paid to the capabilities of remote alerts. It is necessary to foresee the number of telephone numbers by which the sensor can automatically send messages. If you plan to install the sensor on the street, then a high class of housing protection must be taken into account. It can be evaluated by the special IP marking with indices no lower than 54. This designation indicates the protection of the device from rain, pollution and mechanical stress.
Popular device models
The range in this niche is very extensive, but experts attribute the following to the most successful and balanced models of security motion sensors:
- Signal XQ 3. Compact device with automatic tuning, microphone and temperature sensor. The best option if you need to service a small area with a high degree of information with modest energy costs.
- “MMS IT Guard”. A fairly simple version of a wired motion sensor for GSM, the limited communication of which is compensated by wide functionality. So, the model supports working with e-mail, voice, sends high-resolution photo materials and MMS.
- PIR MP Alert A9. Standalone model of GSM-sensor for street use, which allows tracking with recording on a highly sensitive microphone.
- Photo Express GSM. An optional optional integrated alarm system with wireless connectivity. The device operates on infrared sensors, has a built-in camera and supports the ability to send messages to 6 mobile phones at the same time.
Installing GSM motion sensors
Motion sensors for the security system are recommended to be installed in a hidden place. The best option is on the ceiling near the door or window opening. Direct installation is done using a bracket, screws or dowels. That is, you may need to drill a wall or ceiling. Also, do not forget that almost all motion sensors with a GSM module are sensitive to thermal equipment, close to radio and electrical equipment. Some models provide a special insulating sheath, but it also increases the dimensions of the device.
Reviews on the use of the device
By modern standards, this device has virtually no analogues in terms of the principle of detection of an unauthorized person in the room. In this regard, many users point to the efficiency of the device, although not without complaints. Negative impressions of the operation of GSM motion sensors are caused by a high false positive rate. Highly sensitive models, when improperly tuned, react to animals, wind, random radio interference, sounds and vibrations. As for the GSM communication channels, despite the advantages of alternative radio-frequency and network modules for wireless data transmission, cellular communication in this case remains the most popular method of notification.
Conclusion
The use of alarms with sets of high-tech sensors has long gone beyond the boundaries of commercial and highly professional fields. Today, such equipment can be found in equipping urban apartments and especially country houses. In optimized versions, the GSM wireless motion sensor is actively used for servicing garages, summer residences and household facilities. The management process practically does not require special attention from the owner and is limited only to a periodic audit with maintenance. At the same time, complete control over the served zone is maintained with a wide range of additional means of automatic notification.