The security alarm system (OS) is an electronic device that will allow you to always be sure of the safety of your home, office, apartment, warehouse, production room, etc. The security system is designed to prevent unauthorized access to the premises.
It consists of a security panel (central) – a device that collects and analyzes information received from security sensors. The same control panel performs the functions pre-programmed in it, which are executed when the sensors trigger. The equipment also includes a control panel that displays the status of the alarm, serves for its programming. The minimum set of equipment also needs to include an uninterruptible power supply (UPS), cable network and, of course, security sensors.
Sensors come in several forms, depending on what factor they respond to. The most common of them are volumetric infrared (IR sensors), magneto contact (reed switches), acoustic, vibrational, ultrasonic, beam, capacitive, as well as sensors with a directional detection diagram.
Volumetric sensors or motion sensors, these are inaccurate names of IR sensors, the sensitive elements of which are the PIR element. This is a sensor that captures thermal radiation. And if the heat spot moves from sector to sector, the system triggers. Among these sensors, there are models that can distinguish between humans and pets by the size of the heat spot. These sensors are not too expensive and quite reliable. Security alarms with such sensors are often used to protect apartments and residential buildings. Although they are quite easy to fool. For example, wear heat-resistant clothing or close the sensor window. Therefore, it is more correct to use other types of security sensors in conjunction with them.
Magnetocontact (reed switches) sensors are mainly used on the first line of guard. They are installed on doors and windows and track their opening or closing. Two magnets are mounted opposite each other: one on the moving part of the door or window, and the other on the fixed part. When the contact between the two magnets is lost, the sensor immediately transmits a signal to the control panel. This type of sensor is the cheapest, very reliable and with minimal current consumption. Although, in the security system, only with such sensors there are a number of drawbacks: for example, you can enter the territory of the protected premises not only through windows or doors – attackers can penetrate, for example, through ventilation shafts or simply break the glass of the window and not open the frame. Therefore, the use of such sensors is recommended in combination with another type of sensors, for example, acoustic.
Acoustic sensors just respond to a loud sound – including the sound of broken glass. In the most modern of them, a microprocessor is installed, which analyzes the sound diagram and does not confuse the sound of broken glass with another sharp sound. In addition, the sounds of breaking different types of glass are stored in the memory of such sensors. It can be ordinary glass, glass reinforced, triplex. This factor significantly reduces the possibility of accidental operation of the security system.
Vibration sensors protect walls from breaking, safes from opening and windows from breaking. As the name suggests, they respond to vibration. These sensors are quite difficult to configure and make more mistakes. They are sensitive to the operation of large mechanisms, the movement of trams, trains.
Ultrasonic sensors work on the principle of a locator. They emit and receive ultrasonic vibrations. If a moving object enters their field of view, the wavelength changes slightly, in accordance with the Doppler law. This serves as a signal for triggering the sensor. In hot shops and long corridors, these sensors are indispensable.
Beam sensors serve to cover large spaces, and consist of a receiver and a transmitter. When a ray is invisible to the naked eye, a trigger occurs. These rather expensive and capricious sensors serve mainly to protect the perimeter. They are placed along the fence, and work constantly in all weather conditions.
Capacitive sensors are used to protect particularly valuable objects. For example, safes or art objects. The principle of their work is based on the creation of a field with a certain capacity near the protected object. If any object gets inside, the field capacity changes, which in turn leads to a security alarm. This type of sensor is very difficult to configure, quite expensive and has considerable dimensions.
Sensors with a directional detection pattern are essentially an IR sensor that has a specific lens. In the direction and shape of the radiation pattern, there are three types of such sensors: curtain (vertical or horizontal plane), veil (hemisphere), corridor (narrow beam). By the name of these sensors it is immediately clear where and why they are used.
The security alarm provides the following security measures:
- Creating physical barriers to the intruder
- Early detection of an attacker
- Staged assessment of the situation
- Intrusion Control Measures
- Video documentation
- Alarm triggering
Modern security systems will be able to inform you about the penetration of strangers into the territory under protection.