SG-BWS-T4
11
3.6.
Sensors Interference
When several safety devices must be installed in adjacent areas, interference between the emitter of
one device and the receiver of the other must be avoided.
SG-BWS-T4 monitors possible interference between photocells and locks out if any interference is
detected.
Suitable installation precautions could avoid any interference issue between similar devices. This
typically applies to cases when many devices are installed side-by side and in line, such as for
systems featuring several goods loading/unloading areas, parallel one to the other and whose
entrance is protected by safety light curtains.
NO
TX
RX
TX
RX
OK
RX
TX
TX
RX
OK
TX
RX
TX
RX
Fig. 8 Sensors disposal in order to avoid interferences
To make sure that photocell parallel beams do not create interference, it is necessary to install the
photocells considering a minimum centre distance D
do
that depends on operating distance D
op.
To
make this concept clearer, the chart below shows it for the S5-ST2, S5-ST4, SL5-ST4 series
photocells.
0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0
2
4
6
8
10
Distanza operativa (Dop)
D
is
ta
n
z
a
d
is
p
o
s
it
iv
i
o
m
o
lo
g
h
i
(D
d
o
)
S5-ST4
S5-ST2
0
0,2
0,4
0,6
0,8
1
1,2
1,4
1,6
1,8
2
0
10
20
30
40
Distanza operativa (Dop)
D
is
ta
n
z
a
d
is
p
o
s
it
iv
i
o
m
o
lo
g
h
i
(D
d
o
)
SL5-ST4
Fig. 9 Distance between equal sensors
