EOS2 SAFETY LIGHT CURTAIN
Calculation of safety distance
The light curtain must be positioned at a distance equal to or greater than the minimum
safety distance S so that the dangerous point can be reached only after stopping the
dangerous movement of the machine (Figure 5).
According to the EN999:2008 European standards, the minimum safety distance S must
be calculated using the following formula :
S = K (t1 + t2) + C
C = 8 (d-14)
where:
S Minimum safety distance mm
K Operator approach speed to the dangerous area mm/sec
t1 Total response time of the light curtain, in seconds sec
t2
Response time of the machine in seconds, i.e. the time taken by
the machine to stop the dangerous movement from the moment
in which the stop signal is transmitted
sec
C
Additional distance that varies according to the application
1
mm
d Resolution mm
Table 2 – Safety distance
Failure to comply with the safety distance reduces or impairs the protection function
of the light curtain.
If positioning of the light curtain does not prevent the operator from accessing the
dangerous zone without being detected, additional mechanical guards must be
installed.
DANGEROUS ZONE
Figure 5 – Safety distance S
English
1
For further information on additional safety distance, refer to EN999:2008.
8 8540738 • 2nd December 2009 • Rev.2