Where to connect Rotax CAN GND?

[jefish]

I’ve confirmed the CANBUS connections from both the Dynon and Rotax 912iS installation manuals, but what about the Rotax CAN GND connections? Do these go to a shared EMS ground pin? Airframe ground? Not connected?

HIC A 6 CAN_H1A >> Dynon EMS 36
HIC A 5 CAN_L1A >> Dynon EMS 37
HIC A 4 CAN_GND1A >> ???

HIC B 8 CAN_H1B >> Dynon EMS 36
HIC B 7 CAN_L1B >> Dynon EMS 37
HIC B 6 CAN_GND1B >> ???

 

[Rhino]

Anything connected to a Skyview system should share a common ground. You could argue that statement really applies to power or analog data connections, and is less applicable for digital data connections, and you might have a point in that regard. Grounding on power or analog data lines is generally used to prevent induced noise from the electrical system or other outside sources. Digital data lines are somewhat less susceptible to this, and are often grounded only at one end. But they aren't by any means immune. Barring anything to the contrary, it's usually a good practice to ground at both ends. The CAN standard doesn't specify grounds at both ends, but many manufacturers of both cables and equipment state it should be done. I would default to that unless you find anything to the contrary. There are numerous ground pins on the D37 connector to facilitate this.

https://www.edn.com/can-bus-grounding-experiments/