Question
Which hole of the Amplifier Unit can the Through-beam Fiber Unit be inserted into?
Answer
It makes no difference which hole it is inserted into, because there is no distinction between the two fibers for a Through-beam Fiber Unit.
With a Coaxial Diffuse-reflective Fiber Sensors (such as the E32-C31), the holes that the fibers are inserted into are set for the receiver and emitter.
Standard Sensors for Detecting Ferrous Metals under Standard Conditions