The high measuring speed combined with the large measuring range of 1500mm are the outstanding characteristics of the UPB ultrasonic barrier. A further outstanding characteristic of  the UPB series are the adjustable transmitter and receiver.

Transmitter (green LED):

The acoustic power can be adjusted with the potentiometer. The max. power (turn clockwise) should be used for big and slow objects and when operating with a large barrier distance. A reduced power (turn counter clockwise) is favourable when the objects are so small, so acoustically transparent or so fast that the sound would go around or penetrate the object with a high power setting. In particular for small or fast objects the appropriate transmitter power must be experimentally evaluated.

The speed and the width of the object are in the following direct relationship:

v <= b / x

v  speed of object [m/s]

b  width of object resp. width of the gap between objects [mm] (the smaller is true)

The value x depends on the distance between transmitter and receiver and also on the transmitter power. The min. value of x is 3. With higher distance and higher transmitter power approaches 30.


A 50mm wide object can be safely detected up to a speed of approx. 1.7m/s (x=30). With small barrier distance even up to higher speed (x=3).

Receiver (yellow LED):

The switching-on delay can be adjusted on the receiver with a potentiometer. The barrier has max. speed without delay (counter clockwise). This should be he normal operation mode. An increased switching-on delay (clockwise) might make sense when small objects (or disturbances) should not make the sensor to switch.


Detection of holes