7
SLC 220
SLG 220
Operating instructions
Safety light curtain / safety light grid
EN
Safety distance to the hazardous area
Limit of the hazardous point
Safety distance (S)
Protection field marking
Tool - upper part
Signal to stop the
hazardous movement
Standstill of the hazardous
movement
t
n
= t
B
- t
A
Tool - lower part
tA
S
tB
≤
75 mm = max. distance for protection against stepping over
To prevent persons from stepping over the protection field
this dimension must be imperatively respected and observed.
Safety distance for multi-beam version SLG 220 (beam distance
300, 400 and 500 mm)
S
Hazardous point
Transmitter
Receiver
Command device
Authorised operation
Mechanical protection
Direction from which the
hazardous area is accessed
The protection using individual beams must be chosen so that bodies or
body parts larger than the selected resolution (beam di beam
diameter 10 mm) of the SLG 220 are detected.
The safety distance is the minimum distance between the SLG 220 and
the hazardous point, which must be observed in order to ensure that
the hazardous point can only be reached after the hazardous move-
ment has come to standstill.
Calculation of the safety distance for the multi-beam light grid:
S = ( 1600 mm/s * T ) + 850 mm
S = Safety distance [mm]
T = Stopping time of the m reaction time of the safety light grid
K = Approach speed 1600 mm/s
C = Safety supplement 850 mm
Example:
Reaction time of the SLG 220 = 12 ms
Stopping time of the machine T = 170 ms
S = 1600 mm/s * (170 ms + 12 ms) + 850 mm
S = 1141 mm
The following mounting heights to EN 999 must be observed:
Number of
beams
Mounting height above reference floor
(Floor) in mm
2
400, 900
3
300, 700, 1100
4
300, 600, 900, 1200
The successor standards of the EN 999 for calculating the
minimum distances of the safety guards with regard to the
hazardous point are EN ISO 13855 and EN ISO 13857.
3.4.1 Minimum distance to reflecting surfaces
During the installation, the effects of reflecting surfaces must be taken
into account. In case of an incorrect installation, interruptions of the
protection field could possibly not be detected, which could lead to
serious injuries. The hereafter-specified minimum distances with regard
to reflecting surfaces (metal walls, floors, ceilings or parts) must be
imperatively observed.
8°
8°
a= 262 mm
Access direction
Receiver
Obstacle
optical axis
Transmitter
reflecting body
(e.g. material container)
Limit of the hazardous point
a=262mm
8°
8°
Table: Safety distance a
a [mm]
D [m]
0
3
5
10
100
200
300
400
500
600
700
800
900
1000
15
20
The effective aperture angle for the SLC/SLG 220 series is ± 4.0° for
a mounting distance of > 3.0 m. Calculate the minimum distance to
reflecting surfaces as a function of the distance with an aperture angles
of ± 5.0° degrees or use the value from the table below:
The correct combination (type, resolution) of transmitter and
receiver always must be taken into consideration. If this is
not observed, this could result in incorrect operation of the
devices due to mutual interference.
Distance [m] between
transmitter and receiver
Minimum distance a
[mm]
0.2 … 3.0
262
4
350
5
437
6
525
Formula:
a = tan 5° x L [mm]
a = Minimum distance to reflecting surfaces
L = Distance between transmitter and receiver