The working principle and five precautions for using the radar level sensor

The radar level sensor is a measuring instrument based on the time travel principle. The radar wave runs at the speed of light, and the running time can be converted into a level signal by electronic components. The probe sends out high-frequency pulses and conducts them along the cable and rod probes. When the pulses meet the surface of the material, they are reflected back by the receiver in the meter, and the distance signal is converted into a level signal, Transmit-reflect-receive is the basic working principle of radar level sensor.

The antenna of the radar sensor emits electromagnetic wave signals in the form of beams. The emitted waves are reflected on the surface of the material to be measured, and the reflected echo signals are still received by the antenna. Every point in the transmitted and reflected beams is collected by ultrasonic sampling. After the signal is processed by the intelligent processor, the distance between the medium and the probe is obtained and sent to the terminal display for display.

And there are five Precautions when using the radar level sensor:

1. Given an accurate measurement range, working beyond the range makes the radar level sensor not only unable to obtain accurate measurement data, but may also cause damage to the radar level gauge. The measurement range should be calculated from the bottom of the tank where the light wave touches. If the tank is special and the bottom is concave, at this time the level is lower than the calculation point and measurement cannot be performed.

2. If the medium has a low dielectric constant, the bottom of the tank is visible when it is at a low liquid level. At this time, in order to ensure the measurement accuracy, it is recommended to move the zero position up appropriately.

3. When measuring low dielectric constant medium, if its level is lower than the measured value of the liquid level, and the bottom of the tank is visible, if you want to make the measurement more accurate, you can adjust the zero point upward to be higher than the bottom of the tank. position. Although the measurement range value can reach the top of the antenna tip, this is only in an ideal state. In reality, the effect of adhesion needs to be considered, so the measurement value should be fixed at least 100mm from the top of the antenna as far as possible.

4. If the measured medium is in constant motion, in order to ensure the accuracy of the measurement, it is recommended to install a bypass pipe on site and fix it at the middle of the bottom of the storage tank. During the welding process, the smoothness of the inner wall of the bypass pipe needs to be ensured. , In order to prevent the irregularities from obstructing the radar level measurements.

5. The radar level measurements varies with the concentration. The foam can not only absorb microwaves, but also reflect them; if there is foam in the tank, determine the thickness of the foam.

In recent years, radar level sensor have been the first choice for many users to measure the height of the liquid level. The use of the product must be properly grasped, so as to reduce the damage caused to the radar level sensor due to faults caused by incorrect operation, and ensure The accuracy of the level sensor also extends the service life of the radar level sensor.