Introduction to features and installation methods of capacitive sensor

Capacitive sensors use various types of capacitors as sensing elements to convert measured physical or mechanical quantities into capacitance changes. XIDIBEI capacitive sensor can detect objects of various shapes and materials (solid, liquid, viscous, powder, etc.), and is widely used in food and pharmaceutical, agriculture, animal husbandry, environmental protection, logistics and warehousing and other industries.

How does it work?

 

Principle diagram

There are 4 basic elements in the capacitive sensor structure, namely,  sensor board, oscillator, trigger circuit and output terminal. The target object and the sensor board constitute the oscillator feedback circuit. When the object is close to the sensor board, the capacitor at the main side of the sensor will generate electromagnetic field, and the nearby part will change the intensity and frequency of oscillation, thus changing the state of the output switch device. The oscillation amplitude decreases when the object is far away from the sensor tip, and increases when it is close. 

Features of XIDIBEI capacitive sensor

XIDIBEI's entire series of products have undergone more than 20 strict tests, including high/low temperature, aging, vibration, impact, drop, power failure simulation, transient pulse group, electromagnetic interference, etc. It has multiple protection circuits, strong anti-interference ability, high repetition accuracy, and the protection level reaches IP67. There are three sizes of M12, M18, and M30. The detection distance is 3mm, 6mm, 8mm  15mm, and 20mm 30mm respectively. The product is stable and reliable, and is applicable to various complex environments.

 

1. High sensitivity

Capacitive sensors have the advantages of high sensitivity and high accuracy, which is one of the reasons why capacitive sensors are widely used in some environments. It has strong adaptability to the environment, ensuring that it can be used normally in harsh environments. Capacitive sensor is very sensitive to acceleration, displacement and other sensing, and can measure small displacement. When non-contact measurement is used, capacitive sensor has average effect, which can reduce the influence of workpiece surface roughness on measurement.

 

2. Good stability

The capacitance value of the sensor is generally independent of the electrode material and only depends on the geometric size of the electrode. Moreover, the capacitor chip has the advantages of high strength, good temperature coefficient and low air dielectric loss. As long as the material and geometric size are reasonably selected, good detection results can be achieved. Compared with the resistance sensor, which will generate heat and cause parameter changes when it is powered on, the detection distance of the inductive sensor will attenuate the non-ferrous metal, and the capacitance sensor is less affected by other factors.

 

3. Simple structure and strong adaptability

The capacitive sensor has simple structure and is easy to manufacture. It can operate under various harsh environmental conditions, such as high and low temperature, strong electromagnetic field, etc. It can still output stably after withstanding severe temperature changes, and there is no significant change in distance. It can operate normally even under high voltage, high impact and overload. In addition, the size of the sensor can be reduced to meet some special measurement requirements.

 

Mounting methods

XIDIBEI capacitive sensor is divided into embedded type and non-embedded type, and their mounting methods are also different. When the detected surface of the embedded proximity switch is installed flush with the mounting surface, other surfaces are embedded in the mounting surface, which is not affected. Refer to the following diagram.

 

Embedded type mounting diagram 

Non-embedded proximity switches cannot be embedded in the mounting surface around the sensing surface of the head, which is easily affected by the mounting surface. Non-embedded capacitive sensors have a longer detection distance. When mounting, the distance between the side of the capacitive sensor must be 3 times of the detection head to prevent interference.

 

Non-embedded type mounting diagram

When multiple proximity switches need to be mounted side by side, in order to prevent mutual interference between proximity switches, please refer to the following diagram.

Side-by-side mounting diagram 

Sensors are regarded as the cornerstone of the interconnection of all things and the bridge between the real world and the network world. For sensors, multifunctional and intelligent will be the inevitable trend of future development.

XIDIBEI, along with the historical opportunities brought by the intelligent era to the development of the sensor industry, has comprehensively improved the research and development capacity and manufacturing level of intelligent sensors, providing strong support for the interconnection of all things.