Datalogic SG4 FIELDBUS Series, Instruction Manual, Page: 23 / 136

GENERAL INFORMATION ON DEVICE POSITIONING
INSTRUCTION MANUAL 13
Under standard operating conditions, machine starting must not be possible while
operators are inside the dangerous area.
Where it is not possible to install safety light curtain very near to the dangerous zone, a
second light curtain must be mounted in a horizontal position in order to prevent any
lateral access, as shown in Figure 4.
Minimum distance from reflecting surfaces
Reflecting surfaces placed near the light beams of the safety device (over, under or lat-
erally) can cause passive reflections. These reflections can affect the recognition of an
object inside the controlled area. Moreover, if the RX receiver detects a secondary beam
(reflected by the side-reflecting surface) the object might not be detected, even if the
object interrupts the main beam.
Figure 5 - Distances from reflective surfaces
Figure 3 - Wrong light curtain
positioning
Figure 4 - Correct light curtain
positioning