Missing CAN GND

Using Arduino General Electronics
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I have this cable connected to a port which shares a RS232 line and a CAN Bus line.

I don't see the CAN GND Pin. >:(

Can I use the RS232 GND in common between the two lines?

Or should I isolate this port from the other CAN devices (ALL with a CAN GND) that are part of the network?

Or should I do both the operations? :slight_smile:

Thank you!

@edit: I forgot. I'm going to have both the RS232 and CAN Ports busy.

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CAN does not require ground to operate.

If you need a ground, use the RS232 ground.

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Then why I always see the CAN GND pin in all the devices?

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For the same reason that RS485 doesn't "need" ground but it is usually provided: to keep the common mode voltage under control.

Here is some discussion from 2013... rs485 - is shared ground required? - General Electronics - Arduino Forum

Also, you may wish to provide power to the CAN devices, which requires ground.

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MorganS:
For the same reason that RS485 doesn't "need" ground but it is usually provided: to keep the common mode voltage under control.

Put another way, RS485 needs ground nearly always (the exception is transformer isolated connections).
most RS485 chips only allow about 7 to 10V of ground difference before they are out of spec, so operating without
some means of keeping the grounds close in voltage is not guaranteed to work (as capacitively coupled stray
voltages in everyday environments can be 50V or more)

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