!
"
§
S
Figure 6: Minimum distance from the hazardous point
!
Height of the light beams above ground
"
Hazardous point
§
Depending on the application and distance, persons must be prevented from standing
behind the protective device.
Example calculation
Machine stopping time = 290 ms
Response time after interruption of the light path = 20 ms
T = 290 ms + 20 ms = 310 ms = 0.31 s
S = 1,600 mm/s × 0.31 s + 850 mm = 1,346 mm
4.3.2
Minimum distance from reflective surfaces
Overview
The light beams from the sender may be deflected by reflective surfaces and dispersive
media. This can prevent an object from being detected.
Therefore, all reflective surfaces and objects (e.g., material bins, machine table, etc.)
must maintain a minimum distance (a) from the light beams. This minimum distance
(a) must be maintained on all sides of the light beams. This applies in horizontal, verti‐
cal and diagonal directions as well as at the end of the device. The same area must be
free of dispersive media (e.g., dust, fog, or smoke).
The minimum distance (a) depends on the distance (D) between sender and receiver.
PROJECT PLANNING
4
8020453/14Q7/2020-04-27 | SICK
O P E R A T I N G I N S T R U C T I O N S | deTem4 Core
17
Subject to change without notice
