Introduction To Five Popular Anti-theft Alarm Detectors
There are many classifications of anti-theft alarms in daily use. When you buy them, you can make different choices according to different classifications.
The following is an introduction to 5 commonly used alarms:
1. Glass break detector: It uses a piezoelectric microphone and is installed at the position facing the glass. Since it only detects high-frequency glass breaking sound effectively, it will not be affected by the vibration of the glass itself and cause a reaction.
2. Infrared detector: Any object will radiate infrared rays of varying intensity due to the difference in surface heat. Infrared detection is mainly used to detect the human body and other intrusive moving objects. When the human body enters the detection area, the stable thermal radiation is destroyed, and a changing thermal radiation is generated. After the infrared sensor receives it, it amplifies, processes, and sends out an alarm signal.
3. Infrared microwave detector: It is one of the commonly used equipment in the alarm system. Its working principle combines infrared and microwave. When the infrared and microwave detectors have alarm signals at the same time, the probe will have an alarm output, which reduces the possibility of false alarms. There are many models of infrared microwave probes, corresponding to different detection distances.
4. Microwave object motion detector: It uses the Doppler frequency shift of high-frequency radio waves as a detection method, which is suitable for open spaces or squares. Microwave is a very high-frequency radio wave with a short wavelength and is easily reflected by objects. According to the frequency drift of the incident wave and the reflected wave, invading objects can be detected.
5. Door magnetic detector: It is a widely used detector with low cost, easy installation, and no need for adjustment and maintenance. The door magnetic switch is divided into movable parts and output parts. The movable parts are installed on the movable doors and windows; the output parts are installed on the corresponding doors and windows, and the installation distance between the two is not more than 10 mm. There are two lines on the output component, the normal state is normally closed output, and the door and window are open for more than 10 mm, the output is converted to normally open.