CANopen
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Network Architecture
WAGO-I/O-SYSTEM 750
CANopen
4.2 Network Architecture
4.2.1 Transmission Media
4.2.1.1 Type of Cable
A bus medium forms the basis for the physical connection of CAN.
With CAN, both the bus coupling and the bus medium are specified according
to ISO 11898 (CAN High-Speed).
According to the cable specification, the Twisted-Pair medium (shielded ca-
bles twisted in pairs) with a wave resistance of 108...132 Ohm is recom-
mended.
Twisted-Pair is low priced, convenient to use and permits simple bus type wir-
ing.
The WAGO CANopen fieldbus nodes are intended for wiring using shielded
copper wire (3x0.25 mm²).
Two important points have to be taken into consideration when designing the
electrical bus medium:
•
the maximum bus length and
•
the required conductor cross section.
4.2.1.2 Maximum Bus Length
The length of the bus is mainly limited by the signal running time and must,
therefore, be adapted to the Baud rate:
Baud rate
Bus length
1 Mbit/s
30 m
800 kbit/s
50 m
500 kbit/s
100 m
250 kbit/s
250 m
125 kbit/s
500 m
≤
50 kbit/s
1000
m
Table 4-1: Maximum bus length dependent on the set Baud rate
