Chapter 3 Installation and Wiring
3-7
3.2.2
CANopen wiring
The CANopen interface uses DSUB 9-pin plug connector. The plug is assigned with the CAN_H, CAN_L and
CAN_GND connections. CAN_H and CAN_L are two physically different bus levels. CAN_GND is the
common reference potential.
Line termination
To minimize the reflections from the end of the cable, a line termination shall be placed close to the 2 ends of
the bus. Connect both ends of the twisted pair cable(CAN_H and CAN_L) to each LT. Use line termination
whose resistance value is 120
Ω
. (5%, 1/4 W maximum)
•
The cable’s resistance value should be 70m
Ω
/m or less.
•
The above diagrams shows the case used the cable connector “XM2D-0901” by OMRON Co.
GP
Termination
Resistance
Shield
D-sub 9 pin (socket)
CAN-L
Signal
name
2
CAN-H
CAN-GND
FG
Shell
3
7
Pin
GP
D-sub 9 pin (socket)
CAN-L
Signal
name
2
CAN-H
CAN-GND
FG
Shell
3
7
Pin
Shield
Shield
LT = Line Termination
Node 1
Node 2
Node n
LT
CAN_H
CAN_L
CAN_GND
Twisted Pair Cable
LT
Diagram 1
Diagram 2
Diagram 1
Diagram 2
