7
EN
SLC 420 IP 69 K
Operating instructions
Safety light curtain
Correct installation
Hazardous machine parts can only be reached
after passing through the protection field
The presence of staff members between the
protection field and hazardous machine parts
must be prevented/avoided (protection against
stepping over)
Unauthorised installation
Hazardous machine parts can be reached with-
out passing through the protection field
The presence of staff members between the
protection field and hazardous machine parts is
enabled
3.3 Alignment
Procedure:
1 The transmitter and the receiver must be fitted parallel to each other
and at the same height
2 Turn the transmitter and monitor the diagnostic window of the
receiver Fix the light curtain, when the LED OSSD ON (green) is on
and the LED signal reception (orange) is off
3 Determine the max rotating angle to the left and to the right, at which
the LED OSSD ON (green) is on and tighten the mounting screws in
central position Make sure that the LED signal reception (orange) is
not on or flashing
3.4 Safety distance
The safety distance is the minimum distance between the protection
field of the safety light curtain and the hazardous area The safety dis-
tance must be observed to ensure that the hazardous area cannot be
reached before the hazardous movement has come to standstill
Calculation of the safety distance to EN ISO 13855 (successor of
EN 999) and EN ISO 13857
The safety distance depends on the following elements:
• Stopping time of the machine (calculation by run-on time measure-
ment)
• Response time of the machine and the safety light curtain and the
downstream relay (entire safety guard)
• Approach speed
• Resolution of the safety light curtain
Safety light curtain SLC 420
The safety distance for resolutions 14 mm up to 40 mm is calculated by
means of the following formula:
(1) S = 2000 mm/s * T + 8 (d - 14) [mm]
S = Safety distance [mm]
T = Total reaction time (machine stopping time, reaction time of the
safety guard, relays, etc)
d = Resolution of the safety light curtain
The approach speed is covered with a value of 2000 mm/s
If value S <= 500 mm after the calculation of the safety distance, then
use this value
If value S >= 500 mm, recalculate the distance:
(2) S = 1600 mm/s * T + 8 (d - 14) [mm]
If the new value S > 500 mm, use this value as safety distance
If the new value S < 500 mm, use a minimum distance of 500 mm
Example:
Reaction time of the safety light curtain = 10 ms
Resolution of the safety light curtain = 14 mm
Stopping time of the machine = 330 ms
S = 2000 mm/s * (330 ms + 10 ms) + 8(14 mm - 14 mm)
S = 680 mm
S = > 500 mm, therefore new calculation with V = 1600 mm/s
S = 544 mm
The safety distance for resolutions 41 mm up to 70 mm is calcu-
lated by means of the following formula:
(3) S = ( 1600 mm/s * T ) + 850 mm
S = Safety distance [mm]
T = Stopping time of the m reaction time of the safety light
curtain
K = Approach speed 1600 mm/s
C = Safety supplement 850 mm
If the effective resolution is more than 70 mm, the detection
of bodily parts is no longer guaranteed; to that end, the risks
such as reaching into, climbing through and reference heights
above the ground must be observed
(refer to DIN EN ISO 13855) The formula (3) is also applica-
ble to the calculation of the safety distance for the effective
resolution from 41 mm to 300 mm
The safety distance between the safety light curtain and the
hazardous point must always be respected and observed If
a person reaches the hazardous point before the hazardous
movement has come to standstill, he/she is exposed to seri-
ous injuries
