Aranet Ultrasonic Distance sensor can measure distances from 0.5 m to 10 m. Still even if the measured surface is in this range it can show error messages if the ultrasonic signal is reflected, scattered, or absorbed too much from the measuring surface. For more stable operation it is recommended to install the sensor as perpendicularly to the measured surface as possible and at least 60 cm from any other objects that can cause unwanted reflections. Ultrasonic distance sensors can’t also measure very uneven shapes or shifting surfaces, for example, large waves, strong streams or big splashes on liquid surfaces.
