German SICK sensor selection instructions

What are the choices of German SICK sensor transmitters in low-cost control systems?

A large part of the German SICK sensor market is the control system. As a control, it is often not very high precision requirements, and it is a few special control points. The user can directly propose to the manufacturer as long as the fixed point control, which can greatly reduce the cost of the cost. Because no matter which type of humidity sensor, the material and manufacturing cost are not too high. The cost is mainly reflected in the testing and calibration of the product, and reducing the test point reduces the cost of the product. Similarly, the post-production home that is currently producing humidity sensors is also working hard to design low-cost humidity switches to meet market demand.

The German SICK sensor is a component that directly contacts the sensitive body with the environment being measured. Unpredictable environmental pollution is the biggest threat to the life of this type of German SICK sensor. In the discussion, some people thought that the principle of light or ultrasound should be used to solve the problem, but the same thing exists in the clean environment to cause interference on the window and the vibrator. Colleagues increase the cost and use it. Therefore, it is currently popular to use a polymer humidity sensor with high precision and stability in a clean environment and at room temperature. A ceramic humidity sensor that can be heated and cleaned in harsh environments and high temperature applications.

 Usually within the linear range of the German SICK sensor, it is hoped that the higher the sensitivity of the German SICK sensor, the better. Because only the sensitivity is high, the value of the output signal corresponding to the measured change is relatively large, which is beneficial to signal processing. However, it should be noted that the sensitivity of the sensor is high, and the external noise that is not related to the measurement is easily mixed in, and is amplified by the amplification system, which affects the measurement accuracy. Therefore, the sensor itself should be required to have a high signal-to-noise ratio and minimize interference signals introduced from the outside.
The sensitivity of the German SICK sensor is directional. When the measurement is a single vector and its directivity requirements are high, other sensors with small sensitivity should be selected; if the measurement is a multi-dimensional vector, the cross sensitivity of the sensor is required to be as small as possible.

(1) The physical property parameters are uneven and vary.

If the temperature non-uniformity of the liquid in the upper and lower layers is not considered, it can be considered that the density is uniform, and it is easy to calculate the weight by volume. However, in a large container of a liquid level sensor, the temperature, density, and viscosity of the measured medium are not uniform, and may vary with time, temperature, etc., causing measurement errors.

(2) The liquid level is not flat.

The liquid level is good and the liquid level is horizontal. Therefore, in addition to the capacitive level gauge using the wall as the electrode, the general level gauge only requires the installation height, and any installation location can be selected at the same height. Ideally, the liquid level is a regular surface, but there will be waves when the material flows in and out, or the liquid to be tested may boil, foam, or have suspended matter on the surface during the production process. The liquid level is uneven. of.

(3) Special circumstances.

The liquid level sensor container often has high temperature and high pressure, or the liquid viscosity is large, or contains a large amount of suspended matter of impurities, which adversely affects the measurement.