How does light and dark operate work with a luminescent sensor?
With light operate, you are trying to detect a target that is more luminescent than the background. Sensing the lighter target will close the normally open output, causing the output to conduct current. With dark operate, you are trying to detect a target that is less luminescent than the background. Sensing the darker target will close the normally open output, causing the output to conduct current. Read the datasheets for the QL50 and the QL55 for more information on configuring the sensor.
