Bench rig out of the training room, moved onto the lab switch this week. CPU 1214C DC/DC/DC, one ET 200SP with an IM 155-6 PN ST and three modules, TIA Portal V17.
I renamed the ET 200SP in Devices & networks from et200sp-bench to cell2-io so it matches the drawing, compiled, downloaded hardware and software. The CPU goes online fine, but device view has the IM as Not reachable, ERROR red on the IM and the CPU ERROR LED flashing. I tried Assign IP address from Online & diagnostics and the accessible devices list is empty apart from the CPU, so I rebooted the pair of them twice and it's the same. Laptop is on the lab wifi, that's how I'm reaching the CPU.
Is the IM dead? It was fine on the bench on Friday. Or does renaming it in the project need something doing to the IM itself as well?
What switch is the rig on now, and does the wifi go through a router to get there?
Accessible devices is DCP, layer 2. It stops at the first router, so from wifi that list will always be empty apart from what you can reach by IP. Get a cable into the same switch as the IM and update the list again.
Cable in, same switch, an unmanaged 8 port thing. Now the IM turns up in accessible devices, but with the old name et200sp-bench and still 192.168.2.11. I assigned the IP by hand from there, it said it worked, and device view still says Not reachable. Screenshot attached.
So the IP is right and it still won't talk. No luck, and I'm not sure what else to poke at.
V17 here too and I've had exactly this after a rename. Post the top entry of the CPU diagnostics buffer. Mine read "IO device failure, cell2-io, Not reachable" and the accessible list showed the old name, same as yours. The two names not matching is the tell, not the IP.
The controller does not find the device by IP, it finds it by name. Your CPU is calling for cell2-io over DCP, the IM answers to et200sp-bench, so nobody replies and the IP you set by hand never comes into it. The CPU would assign its own once it found the device anyway.
One thing to do: Online access, your Ethernet card, Update accessible devices, right click the IM, Online & diagnostics, Functions, Assign PROFINET device name, pick cell2-io, Assign name. The IP follows from the CPU on its own.
There's a writeup on the name versus IP part here: https://plctr.com/advanced-plc-networking-and-communication-protocols/
Assigned the name from Online access this morning. The IM went green after a few seconds and the IP changed to 192.168.2.11 on its own, I didn't touch it. CPU ERROR LED only went out after a power cycle.
So I renamed the device in the project and never gave the real IM that name, and the wifi hid the whole thing from me because the naming runs at layer 2. A cable into the lab switch and Assign PROFINET device name sorted it.
One thing I still don't get is why the manual IP assign reported success if the CPU never uses it. Maybe it does land and the CPU writes over it, no idea. Thanks suel and petek.
Marking solved. Moved from Networks & Comms to Siemens.
plctr.com team