Safety Distance Calculation - schmersal SLC 412 Instructions De Montage Et De Raccordement

SAFETY DISTANCE CALCULATION

The light curtain / light grid must be installed at a distance that is greater than or equal to the
minimum safety distance S, so that a dangerous point can only be reached after all
hazardous machine movements have stopped.
According to EN 999, the minimum safety distance S must be calculated using the following
formula:
S
K
t
1
required for the machine to interrupt the dangerous movement
t
2
C
The non-observance of the correct safety distance reduces or cancels the protective
action of the light curtain / light grid.
If the position of the light curtain / light grid does not prevent the operator from
having access to the dangerous area without being detected, additional mechanical
guards must be installed to complete the system.
6
minimum safety distance
approach speed of object to the dangerous area
response time of the safety light curtain / grid in seconds
machine response time, in seconds, meaning the time
following transmission of the stop signal
additional distance
S
"S"=Safety distance
S = K (t + t ) + C
1 2
Figure 3
mm
mm/sec
sec
sec
mm
HAZARDOUS
MACHINE