AFAIK No.
I may be wrong here, but isn't Profinet communication only possible between an I/O controller (Master) and an I/O device (Slave)?
If so, then your robot system needs to be configured as the I/O controller on the Profinet network to be able to communicate with more than one other unit.
But then again, I may be wrong.
I have only used Profinet where the PLC is the I/O controller, and of course it needs to be able to communicate with all the various PN I/O devices it's connected to (drives, I/O nodes, robots etc.).
Aah, yes that would be a possibility:
- already working connection: PLC is controller, robot is device;
- new connection: PLC is device, robot is controller.
or of course:
robot is controller and both PLC are devices.
Depending on the PROFINET option you have, the robot controller can be a controller and a device at the same time.
However, the function jleblanc is looking for is PROFINET Shared Device, which gives multiple IO controllers access to the same device. As far as I know, Fanuc does not support the shared device function. Neither the Siemens CP16xx nor the Molex option.
There are actually some of avabile standarized configurations that you can make. You just have to check on your plc supplier what type of net configuration is the best for you. You can communicate with wifi between plcs of course.
I attach an example. PLCs can communicate with each other to transfer data between devices nad plcs itself. A device is wide term and you can controll with PLC2 robots, vfds, etc that are connected to PLC1
... However, the function jleblanc is looking for is PROFINET Shared Device,. ..
This could be one solution if Fanuc would support, but doesn't, he is looking for a possibility to connect a second plc to the robot, and therefore the above mentioned options are possible.
Like it is the another possibility. But this way you can bypass buying additional options for robot.
And of course you don't have to have PCs connected to the net
No. AFAIK it's not.
Read and understand the posts above.
Everything is said, but not from everyone.
If you are under devices and network & in network view you should add the robot. Probably you must download some libraries for your robot to add for TIA Portal
Setting up profinet with cp 1604 and J709 isn't that easy like drawing green lines in a sketch and loading a downloaded library 
.
You must create a project in Tia with a pc station and cp 1604, setup some parameters, load the project to the cp1604, export a gsdml file. Then you have to import this gsdml file into your real TIA project (like mosbe tried to show) and setup the device there.
But according to your first post this should have already be done, because this connection already is working.
Now you need the other way round: PLC as device and robot as controller. This way I haven't done yet. But think you have to create an i-device in your project, export the gsdml file, import that file in Fanuc and then configure it in profinet configuration on Fanuc.
Do you have the profinet documentation of Fanuc?
You only need the shared device option if your plc is device for at least two controllers (one for the Fanuc and one for another plc or Fanuc or wathever).
Don't know if plc can be controller and device at the same time.
Then You don't have the newest documentation.
In the documentation B-82864EN_05 in appendix I there is an explanation of configuring devices with TIA portal.
Is it too hard for you to find tia portal tutorials? There are lots of them
Thanks hermann for your help.
I had not looked in the appendix.
And mosbe I'm really sorry for not finding what I needed on my own. But If I'm here, it's because I've done a lot of search on this subject before making this post. There's a lot of tutorials for the I-Device set-up but not for the I-Controller set-up.
Is it too hard for you to find tia portal tutorials? There are lots of them
This is true, but I think Fanuc at this point doesn't make a good job.
We (most people here in the forum) just want to configure a profinet device / controller on a ROBOT and have to handle a big part of software (TIA portal) that cost very much money, needs a powerful computer and every newbie needs days / weeks or even months to get comfortable with it. In one of my cases even a professional TIA programmer had problems to configure the profinet connection, and we had a better documentation from the Fanuc hotline.
Yeah fanuc sucks at this but I meant tia portal tutorials (as I understood). I didn't mean to be rude, sorry
