CANopen
• 79
Network Architecture
WAGO-I/O-SYSTEM 750
CANopen
If the bus level is in the recessive status, the voltage between CAN_Low and
CAN_GND is 2.5 V and also 2.5°V between CAN_High and CAN_GND.
This means that the differential voltage is 0 V.
If the bus level is in the dominant status, the voltage between CAN_Low and
CAN_GND is 1.5 V and 3.5°V between CAN_High and CAN_GND.
Then differential voltage is approx. 2 V.
Note
When connecting subscribers, ensure that the data lines are not mixed up.
At its conductor ends, the bus cable must always be connected with a match-
ing resistor of 120 Ohm to avoid reflections and, as a result, transmission
problems.
This is also required for very short conductor lengths.
CL+
M
S
17
18
22
75
0-3
07
8
7
6
5
4
3
2
1
ON
RT
RT
CAN_High
CAN_Low
RT = 120 Ohm
Fig. 4-2: Connection principle of a WAGO fieldbus node to the CAN bus
g012402x
Before starting the buscoupler on the network, the installation should be
checked. The physical connection can be checked in the CAN fieldbus with an
ohmmeter at any place. You have to remove all connections to other devices
except for the terminating resistors.
