Editorial Team Editorial Board Members

Combined sensors are a combination of two sensors built on different physical principles of detection, combined structurally and schematically in one housing. Moreover, they are schematically combined according to the "I" scheme, i.e. only when both sensors are triggered, an alarm notification is generated. The most widespread combination of infrared passive and radio wave sensors. Combined security sensors have a very high noise immunity and are used to protect the premises of objects with a complex interference situation, where the use of other types of sensors is impossible or ineffective.
Mixed sensors are two sensors built on different physical principles of detection, combined structurally in one housing. Each sensor operates independently of the other and has its own detection zone and its own output for connection to the alarm loop. The most widespread combination of infrared passive and sound sensors. There are other combinations.
Alarm sensors are designed for manual or automatic alarm notification to the internal security panel of the facility or to the internal affairs bodies in the event of a possible criminal attack on employees, customers or visitors of the facility.
Various buttons and pedals of manual and foot action based on a magnet and electric contact sensors are used as alarm sensors. As a rule, such sensors are locked in the pressed state and return to the starting position is possible only with the help of a key.
For the same purposes, special mini alarm systems operating over the radio channel have been developed and are being used. They include a receiver connected to a receiving control or control panel device, and several wearable fob-transmitters for wireless transmission of alarm notifications. Some key chains include a drop sensor. The range of such systems ranges from several tens to several hundred meters.
A special place among alarm sensors is occupied by trap sensors. They are designed to provide an alarm notice in case of an attempt to steal money or rob a protected object, regardless of the actions of the staff. They are an imitation of a bundle of money in a bank package with a volume of 100 bills, in which a magnet is mounted, and a magnetic sensor (reed switch) is installed in a special stand on which the bundle is located. When the imitation bundle of money is forfeiture (moved) from the stand, the contacts of the magnetic sensor are opened and an alarm notification is sent to the object's security console. There are similar trap sensors in which, together with a magnet, a special cartridge containing colored (orange) smoke with a volume of 5 cubic meters is embedded. The smoke composition is sprayed with a time delay (3 min) after the magnetic sensor is triggered.