The porosity of the surface has a significant impact on the sound reflection of the object to be measured. Materials with a high porosity, such as polystyrene or foam, absorb the sound to a very high level, so that little sound can be reflected and perceived by the sensor. Materials with a low porosity such as metals reflect most of the sound waves and can therefore be easily detected. As a general rule, smooth, hard and vertical surfaces offer the best reflection.
Our sensors can be used in environments with an absolute pressure of 1 bar.
The sound generator/transducer is chemically resistant to household cleaning agents and can be easily cleaned with them. Solvents for epoxy resin, on the other hand, are not suitable.
Due to their design, our ultrasonic sensors are only suitable for applications with air as the transmission medium. The sensors cannot be used directly in liquids.
Ultrasonic sensors are also suitable for measuring levels in tanks. However, it is important to ensure that the sensor does not detect the walls of the tank by mistake instead of the liquid at a low liquid level.
You can find the specific response curves on the product detail pages of the ultrasonic sensors.
Environmental factors such as wind and warm ascending air, in particular, can strongly distort the sensor’s sound field and thus impair the measurement. This is especially true if the object to be measured emits heat into the ambient air.
Ultrasonic noise from other sensors or machines can also influence the measurement result and prevent a reliable measurement.
To record the response curve, the measured object, e.g. a 100 × 100 mm plate, is guided into the sound field of the ultrasonic sensor from the right and left. The output switches as soon as the sensor detects the front edge of the measured object. The front edge is represented by a blue line, while the black line marks the center of the measured object at the time of switching. On the product detail pages, the response curves always refer to the position of the center of the measured object (black line). For this reason, half the object width (50 mm for a plate of 100 × 100 mm, 12.5 mm for a round rod of 25 mm) is subtracted to determine the sonic cone width. If the black line, e.g. at 1,200 mm, has a width of +/–65 mm, the actual sonic cone width is +/–15 mm.