schmersal SLC 410 Instructions De Montage Et De Raccordement page 57

DISTANCE TO REFLECTING SURFACES
The presence of reflecting surfaces in proximity of the photoelectric light curtain / light grid
may generate spurious reflections that prevent monitoring. With reference to Figure 19,
object A is not detected because surface S reflects the beam and closes the optical path
between the Emitter and Receiver. A minimum distance d must therefore be maintained
between any reflecting surfaces and the protected area. The minimum distance d must be
calculated according to the distance l between the Emitter and the Receiver, considering that
the angle of projection and reception is 4°.
Figure 20 illustrates the values for the minimum distance d that must be maintained when
the distance l between the Emitter and Receiver is changed.
After installing the system, check whether any reflecting surfaces intercept the beams, first in
the centre and then in the vicinity of the Emitter and Receiver. During these operations, the
red LED on the Receiver should never, for any reason switch off.
Figure 19
Figure 20
21