Capacitive proximity sensors really come in handy when it comes to protecting your property and yourself. These sensors can be used to detect the presence of an object or person that is around the corner where vision is not possible. Capacitive proximity sensors have become increasingly popular in the modern perimeter security strategy, deployed especially to protect large commercial properties.
A capacitive proximity detector is a proximity sensor that can detect nearby objects without any physical contact.
Proximity sensors are used in a variety of applications, ranging from robotics to automotive, to industrial automation, and so on. The basic principle behind a proximity sensor is the detection of an object or material without actually making physical contact with it. Capacitive proximity sensors are one of the most popular types of sensors used today.
A capacitive proximity sensor detects alterations in the electrical capacity between conducting plates that are separated by an insulator. This is similar to the working of a capacitor, which consists of two metal plates that are separated by the insulator, dielectric, or an air gap. An object placed near this capacitor will change its capacitance, and this change can be sensed electronically to detect the presence of that object.
Capacitive proximity sensors are ideally suited for the detection of persons trying to overcome or bypass a fence or wall. They also detect massive impacts on fences and walls, e.g., when driving through a fence with a vehicle.
The sensors are mounted on the outside of the fence or wall, and the electric field extends up to 3 m on each side (dependent on the model). The advantage of this technology is that it does not rely on the electric conductivity of objects. They detect any object that moves into their detection range – regardless of material and shape. The electric field is invisible and harmless to humans.
The main advantages of capacitive proximity sensors are their excellent detection reliability since the sensor registers changes in the capacitance as soon as an object is detected. They are more reliable than inductive sensors when detecting transparent media such as glass, plastic, or plexiglass.
The big disadvantage of capacitive proximity sensors is the somewhat elaborate installation. This makes them unsuitable for mobile applications.
With their increased popularity, the future looks promising for capacitive proximity detectors. The demand for higher levels of protection and the advent of smart electricity systems that recognize when the devices are in use will keep this product on top of the game. The next decade will likely bring even better results in terms of increasing security and convenience to consumers, helping many make the right choice when it comes to sensors.