Reflex light barriers use LED red light for contactless object detection. If the light beam between the sensor and the defined background is interrupted, the sensor switches. The functional principle is based on a detection method that integrates both the energetic and the triangulation principle in one sensor.
Reflex light barriers can detect semi-transparent objects. The use of a static reference background, such as a stainless steel end piece, is recommended for the application. For particularly transparent materials, it is advisable to use retro-reflex sensors for transparent objects.
Dynamic readjustment dynamically adjusts the taught-in switching thresholds to gradual changes in the signals (e.g. in the event of slow contamination of the optics). This prevents the sensor from being taught in again.
A distinction must be made between the same remission between object and background and different remission. In the case of different remission, the hysteresis is not relevant, as the sensor detects the object based on the difference in intensity. With the same remission between object and background (example, white 90% remission), a switching hysteresis of < 5% is defined for P1PM sensors.
