Can't the ultrasonic flowmeter detect the signal?

Suggested method:
1. Confirm whether the pipeline parameters are set correctly, whether the installation method is correct, and whether the connecting wires are in good contact; Whether the pipeline is filled with fluid and whether the measured medium contains bubbles;
2. Whether the ultrasonic sensor is installed according to the installation distance displayed on the ultrasonic flowmeter host, and whether the sensor installation direction is incorrect.
3. Check if there is insufficient coupling agent in contact between the sensor and the tube.