Pilz PSEN op4F-A Series Operating Manual page 63

OPERATING MANUAL
The existence of the tolerance is indicated by LEDs flashing on the user interface, as shown
below.
Tolerance active
The tolerance affects the light curtain's actual resolution. Make sure
that the new resolution is considered when calculating a new
mechanical assembly.
Position tolerance
Dimension tolerance
1003067-EN-04
Tolerance display
LED 3 flashes yellow
PSEN op4F/H-A series
LEVEL
63