Operating Instructions
Chapter
4
C 4000
Installation and mounting
8 009 221/16-11-00
©
SICK AG • Safety Systems • Germany • All rights reserved
23
Fig. 15: Safety distance from
the point of danger
How to calculate the safety distance S according to EN 999 and EN 294:
>
First, calculate S using the following formula:
S= 2000 × T + 8 × (d – 14) [mm]
T = stopping/run-down time of the machine
+ response time of the protective device [ms]
d = resolution of the light curtain [mm]
S = safety distance [mm]
The reach/approach speed is already included in the formula.
>
If the result S is
£
500 mm, then use the determined value as the safety distance.
>
If the result S is
>
500 mm, then recalculate S as follows:
S = 1600 × T + 8 × (d – 14) [mm]
>
If the new value S is
>
500 mm, then use the newly determined value as the minimum
safety distance.
>
If the new value S is
£
500 mm, then use 500 mm as the safety distance.
Example:
Stopping/run-down time of the machine = 290 ms
Response time = 30 ms
Resolution of the light curtain = 14 mm
T = 290 ms + 30 ms = 320 ms = 0.32 s
S = 2000 × 0.32 + 8 × (14 – 14) = 640 mm
S
>
500 mm, therefore:
S = 1600 × 0.32 + 8 × (14 – 14) = 512 mm
Protective field height
Safety distance S
Distance to avoid standing behind
the safety curtain
£
75 mm
Point of
danger