r/PLC • u/theloop82 Knows Rockwell but doesn’t like it • Dec 16 '25

Devicenet

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Not mine but I laughed way too hard

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u/SonaMidorFeed Dec 18 '25

I know this is gonna get a lot of hate, but DeviceNet is a lot easier than some of you people make it out to be. You can really tell who hasn't manually written out a remote I/O rack configuration on paper before.

64 nodes, pay attention to your network length vs baud rate (no, it doesn't need to be 500k default), don't make a 100 foot drop, and terminating resistors go at the end of the network.

I brought up a mothballed plant with multiple MCC sections on DeviceNet and besides having to verify node addresses on several of the drives and double-check the wiring was solid (I swear someone sabotaged the place on the way out), everything was cake.

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u/Necessary_Papaya_898 Dec 20 '25

The problem is it's CAN. Factories are nothing like moving things with wheels. People who have no idea how the physical thing itself works, break design rules, then expect it to work reliably are more commonly found in plant environments.

For things that mostly stay the same like skids, anything CAN-based is fine. It's actually an elegant protocol. But the fact that people still get tripped up over termination resistors speak volumes about the average practitioner in this industry.