Determination Of The Cable Length - Example - SICK T4000 Serie Instrucciones De Servicio

5
Chapter
Tab. 2: Maximum
cable lengths
Fig. 5: Example
installation of
cable lengths
156
© SICK AG • Industrial Safety Systems • Germany • Subject to change without notice • 8012206/UC32/2010-11-15
Electrical connection
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Max. number of switches
5
6
10
5.4.3 Determination of the cable length – example
In the example 6 safety switches are used in series. 40 m
of cable are laid from a safety relay in the control cabinet
to the first switch, and 20 m between the individual safety
switches.
L = 40 m
1
i =
out
min. 75 mA
The safety relay draws 75 mA on the two safety inputs.
It operates in the entire temperature range at 19.2 V
(24 V –20%).
i (mA)
out
Possible output
current per channel
OA/OB
10
25
50
100
200
300
400
10
25
50
100
200
300
400
10
25
50
100
200
300
400
L = 140 m
max
L = 5 x 20 m
2
L = 20 m U
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Operating Instructions
T4000 Direct Unicode
L (m)
1
Max. cable length
to the first switch
150
100
80
50
25
15
10
120
90
70
50
25
15
10
70
60
50
40
25
15
5
= min. 19.2 V
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