The D-SUB C6/C7 connectors are used for CANopen connection. The default baud rate is 500Kbps, the maximum acceptable value is 1Mbps.
The CANopen GND is galvanically isolated from zero signals inside the card. The cable used to connect CANopen must be shielded. The shield must beconnected to the ground network, for this purpose the C6/C7 connector is metallic and is connected to PE.

The connection CANOpen must be made with a pair of shielded cables having the following characteristics:
• Characteristic impedance of 100Ω ≤ Z ≥ 120Ω
• Exercise capacity ≤ 60pF / m.
You can insert a 120Ω termination resistance by a jumper between pin 8 with and pin 7 in either C6 or C7 connectors.

Here's an example of connecting a CANopen master with 3 devices.
For electromagnetic compatibility reasons of the case of Sub D connector must have these characteristics:
• Metallic body or covered in metal body
• Possibility of connecting the cable shield directly to the metal body of the conductor by means of a secure and spacious connection.