Brief introduction of security products (2)

Intrusion detector

Point control

This is a series of intrusion detectors with a small warning range and limited to local control. It is characterized by simple structure, stable operation, easy installation and low price. The disadvantage is that the prevention is not strict enough.

Magnetic switch intrusion detector

Magnetic switch intrusion detector: also known as magnetic switch. It is composed of permanent magnet and reed switch. The dry reed pipe, also known as the tongue reed pipe, is constructed by encapsulating two or more soft iron electrodes in a sealed glass tube filled with inert gas. In the natural state, the two electrodes not in contact are called normally open, and the ones in contact are called normally closed. Among them, the normally open type is widely used. It is installed on the frame of the door or window, the electrode is connected to the controller with a wire, and the magnet is installed on the door or sash, close the door and window, and move the magnet to make it just close (when the magnet approaches The soft iron electrode is magnetized and closed due to the attraction of the opposite sex). When the controller is opened, the doors and windows enter the alert state (or arming). At this time, the door and window are opened again. Since the magnet is away from the reed switch, the electrode demagnetization is automatically disconnected, and the controller emits an audible and visual alarm. Due to the simple installation, the residents can control the room door, balcony door and all windows by themselves. In addition to magnetic switches, micro switches, stroke switches, mercury switches, tension switches, etc. can be used simultaneously. All kinds of contact switches that disconnect the contact under the action of external force and can automatically reset after the external force disappears can be used in conjunction with the alarm controller. We used this principle to collectively call it switch alarm. This kind of alarm has a wide range of applications, and is often used in anti-theft systems of various sizes. However, its shortcomings are due to the lack of strict protection areas and parts, and large loopholes, which are rarely used alone.

Glass breakage intrusion detector

Using the piezoelectric effect of piezoelectric ceramics (the piezoelectric ceramics will generate charge on its surface when twisted and deformed under the action of external force), glass breakage intrusion detectors can be made.

Attach the detector to the door and window glass. The upper and lower surfaces are connected to the control circuit with wires. Once the glass is struck or broken by gravity, the piezoelectric effect is generated. After the control circuit processes, the alarm will generate an audible and visual alarm. Whether the alarm should be determined by the control circuit. Vibrations caused by cars passing, people walking, windy, etc. should be eliminated, and the alarm will only be given when the glass is hit. This reduces a large number of false alarms. Glass with different thicknesses and specifications ranging from tens of square centimeters to a few square meters can be used. Pay attention to the firm and reliable paste during installation, if used in conjunction with the switch-type alarm, the effect is better. It is the most simple and practical set of good anti-theft alarm system to integrate the door lock control into one in the residential house.

Video screen intrusion detector

Within the field of view of the camera, a video alarm controller is used to set the protection target, which is memorized after confirmation. An alarm signal can be generated when the protection target is moved or new items are added. The number of points and the size of items are not limited, and can be increased or decreased at any time, which is very convenient to use. The only shortcoming is that the camera must be turned on as long as it is armed, which will affect the lifespan.

Touch-inductive intrusion detector

Touch detectors often use conductive cloth, conductive film or metal wire to protect safes, cultural relics cabinets or other valuables and exhibits. Someone can trigger an alarm if they touch it in time. In the home, we can arm around the balcony, the guardrail, the outdoor unit of the air conditioner, etc. Once someone attempts to climb, an alarm can be issued.

Inductive detectors are mainly armed with metal wires, and the warning range can be appropriately expanded. For example, a warning line can be erected around the museum of cultural relics and showcases to prevent people from approaching and touching cultural relics exhibits. stop. The advantages of this kind of product are flexible arming and flexible, and the range can be large or small. The disadvantage is that due to the large influence of environmental humidity and temperature, the sensitivity should be adjusted frequently.

Point control products commonly used in entrance and exit control and access control systems

Various locks: push-button, touch-type electronic combination lock; magnetic card lock; IC card lock; retina lock; fingerprint lock; voice control lock, etc.

Combination lock of electronic lock and mechanical lock. Install this kind of lock on the door of the house. Usually, you can use the key to open the door. The master goes out to open the alarm, close the door and enter the alert state. Back home, the key opens the door and the alarm is turned off. Even if someone steals the key to open the door in the alert state, but the security cannot be disarmed without knowing the password, an alarm will be issued after a few seconds. If you pry the door and pry the lock and try to break the door, you will immediately call the police.

Building intercom anti-theft door: commonly used for public prevention of unit buildings. Install electronically controlled anti-theft door, door closer and control keyboard at the door of the unit building. Any resident of the unit can use the key to open the door and enter the building, and the door closer will automatically close the door. Relatives and friends can use the control keyboard to press the corresponding signal, and the intercom in the master room will make a sound. After confirming the identity of the intercom, press the door lock open button to open the unit door. Irrelevant personnel cannot be mixed in easily, so that the safety in the unit is guaranteed. When you go out, press the unlock button in the door to enter and exit freely. Visual intercom As long as a miniature camera is installed on the control keyboard outside the unit door, the host can see the visitor himself through the liquid crystal display screen during intercom to prevent bad people from posing. This anti-theft door was widely used in coastal open cities such as Guangzhou, Fujian, Hainan and Shenzhen as early as the early 1990s, and northern cities have also been installed and used in recent years. When using this kind of door, it should be noted that anyone who does not know when opening the door intends to follow up. Once followed up, it will pose a threat to the safety of this unit.

Other common point-controlled alarm products

Pressure pad: Place the cultural relic exhibits on the pressure pad and send an alarm once it is removed. Put a pressure pad under the carpet and an alarm will be generated when someone walks. Put the pressure pad under the driving seat of the car, and someone can also call the police if they steal the car. The application range is very large.

Anti-theft camera: Linked with other intrusion detectors, once someone moves in the prevention area, the camera takes pictures continuously while alarming.

Anti-theft alarm for motor vehicles: Slamming glass, opening doors, stealing tires, and starting cars can all trigger alarms. You can call in the car, you can report to the pager, you can also report to the alarm center. After receiving the alarm, the police reception center can immediately dispatch criminals to arrest them; if they have left, they can track the robbery through an electronic map.