FIESSLER
E L E K T R O N I K
10
4.1 Safe distance from hazardous area
The safe distance (S) between the accident-preventing light barrier and hazardous area must be big enough to ensure that when
the protective field is penetrated, the hazardous area cannot be accessed before the hazardous movement has been
ended. In addition, it must be ensured that reaching over, under or around, or walking behind the protective field is
prevented by additional mechanical screening or further light barriers. To this end, please also refer to EN 999 and
other effective national and international safety regulations.
4.1.1 Vertical light barrier protection of hazardous areas
The safe distance S is calculated as follows:
- K = Grabbing speed or approach speed
For the grabbing speed K, a speed of 2000 mm/s is preset. If the calculation
for S produces a value greater than 500 mm, the calculation can be repeated
with 1600mm/s if this does not lead to a value lower than 500 mm (smin > 100
mm)
- T = t1 + t2
t1 = Response time of the safety device
t2 = Run-on time of the machine
With ULVT light barriers, the response time of the safety
device
t1 depends on the number of beams (refer to Table 10/1).
When using the ULVT with the optional safety
switchgears, the
response time of the switchgears is added to t1:
For LSUW N1 Muting switchgear:
20 ms
For LSUW NSR 3-1K switchgear:
25 ms
For ULSG switchgear:
6 ms
The run-on time of the machine t2 must be specified by the
machine manufacturer.
- C = 8 (d - 14 mm) d = Definition of the safety device
(minimum detectable obstacle size)
The definition capacity d ( = 14 mm
or 30mm
) is specified on the nameplate of the ULVT light barrier,
for d =14mm => C=0, for d= 30 0> C= 128mm
Calculation examples for the safe distance with vertical area protection using ULVT light barriers
≥
Example 1:
ULVT100/13 safety light barrier
Run-on time t2 of the machine from 75 ms
S = 2000 mm/s x (0.075s + 0.006s)
S = 162 mm
Example 2:
ULVT500/35 safety light barrier
ULSG safety switchgear
Run-on time t2 of the machine from 75 ms
S = 2000 mm/s x (0.075s + 0.007s + 0.006s) +8(30mm-14mm)
S = 304 mm
Table 10/1 Response time t1 of the ULVT light
barriers (standard form factors)
S
Nachlaufweg
der Maschine
4 Installation
- Safe distances
S = (K x T) + C
Fig. 10/1 Vertical protection of hazardous areas
For S = 100 mm to 500 mm:
For S > 500 mm:
S = (2000 mm / s . T)
S = (1600 mm / s . T)
BA - ULVT
Run-on path
of the machine
Protective field
height / no of
smallest
obstacle
14mm
reaction
time
(ms)
14mm
Protective field
height / no of
smallest
obstacle
30mm
reaction
time
(ms)
30mm
ULVT100 /13
6
ULVT100 /7
5
ULVT200 / 26
7
ULVT200 / 14
6
ULVT300 / 39
8
ULVT300 / 21
6
ULVT400 / 52
9
ULVT400 / 28
7
ULVT500 / 65
10
ULVT500 / 35
7
ULVT600 / 78
11
ULVT600 / 42
8
ULVT700 / 91
12
ULVT700 / 47
9
ULVT800 / 104
13
ULVT800 / 56
9
ULVT900 / 117
14
ULVT900 / 63
10
ULVT1000 / 130
15
ULVT1000 / 70
10
ULVT1100 / 143
17
ULVT1100 / 77
11
ULVT1200 / 156
18
ULVT1200 /84
12
ULVT1300 / 169
19
ULVT1300 / 91
12
ULVT1400 / 182
20
ULVT1400 / 98
13
ULVT1500 / 195
21
ULVT1500 / 105
13
ULVT1600 / 208
22
ULVT1600 / 112
14
ULVT1700 / 221
23
ULVT1700 / 119
15
ULVT1800 / 234
24
ULVT1800 / 126
15
ULVT1900 / 247
25
ULVT1900 / 133
16
