Link tags between 2 PLC that not in the same network

Is it possible to develop nanopi r2s become device that can link tags between 2 PLC that is not in the same network group... for this project I need also create the nanopi r2s EDS file which it will be use by the PLC network configurator to tags link with it

So long as the pi can communicate with both PLC then yes.

Couple of questions...

  • What is the nature of the link - process signals for production (critical/important to keep production running/interlock) OR simple data sharing (non critical/production will continue if link is lost)?
  • Is this Omron or AB PLC? Or something else?

For anyone else reading, the menton of EDS and tag link means the OP is referring to
the industrial CIP protocol EtherNet/IP, implicit messaging.

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Thank you Steve... the link is EtherNet/IP... I will be use Omron PLC and using NetConfigurator ... Here I attach the sketch of network that I will be apply to my design.. The RED circle is nanopi r2s... I also very new and still under purchase this nanopi r2s.. even working with nodered also never have experience...

@sawal few more questions before I advise...

  1. what is the subnet mask of the 172.168.x.y network?
  2. are the networks physically connected
  3. are these separate (non routed) VLANs or same VLAN?
  4. what is the nature of the intercommunication...
    1. PROCESS/INTERLOCK or just staring status?
  5. Must the communication be EtherNet/IP (EDS development is tricky)
    1. Could you use FINS Ethernet Protocol instead?
  1. Main PC that which is all PLC data will be collect subnet must 255.255.255.0
  2. All network physically connected
  3. separate between network PC have 2 Ethernet port, both PLC server also have 2 Ethernet port... ( my issue that why I need nanopi r2s is because... at first LINE machine (see attachment: G1 LINE ) each machine before this unconnected each others and IP most of PLC is copy(same) so I need to rearrange the IP and reconfigur all machine for this LINE in other to connected is possible... these process take a lot of time that I cannot have due not allowed by production stop the machine to long...and reconfigure machine IP is very risky to mistake as the machine is not our design and some even complex ( a lot IP device )... for next LINE (P3 AUTO LINE) which is under progress design I don't want to reconfigur the IP so the nanopi must be success apply.
  4. no interlock... just only taking the machine status for production monitoring.
  5. Don't change concept as current first LINE is now working...

What you are asking is feasible - sure.

On a similar job I did, I took a different approach. I added routers to the standalone PLCS and accessed there values without linking 2 PLCs via an EtherNet/IP bridge. This got past the "Same IP address" issue since the router created PAT addressing.

Another option (if stand alone PLCs are CS/CJ) is to add another EIP21 card and add that to the NJ PLC SERVER network (for direct EIP comms between standalone PLCs)

concept is irrelevant as you are taking values from PLC to PLC (the protocol is irrelevant) - the reason I say this is there is the node-red-contrib-omron-fins node that is much easier to get working (and is proven to work with different networks, across routers etc)


NOTE: When i say router - this could be an off the shelf device or even a Rasperry PI running IP Tables. the point is you can remap the IP addresses (using NAT or PAT) to avoid "same IP address" conflicts.


Hope some / any of that is helpful

You are correct... it actually CJ2M plc for most of the machine but few others is different brand plc... add another EIP21

cost is very high compare using nanopi... for my project need up to 30 set of nanopi...

The nanopi probably comes with IPTABLES installed (or UFW) wither way, it can be installed to act as a PAT or NAT router meaning you can simply uplink the PLCs to a "common network" where node-red can access all PLCs

Thanks Steve... anyway I would like first try to play around with Ethernet/IP, create EDS file and any item related to link by tags can be success... so is there some reference for these that I can start with and explore as a beginer...?

EtherNet/IP is a complex beast. EDS files are one of the most unintuative things I have EVER used and while it is an open standard, you pretty much need to be a paid up member ODVA to get anywhere useful

You can try the EZEDS application

NOTE: OMRON Network configurator makes tag link simple - but that is for field level communications when you have a good working EDS file.

Hi Steve... I receive Nanopi r2s from Friendly Elec with below spec...

How to apply Node red? the OpenWrt preinstall... by it only is it possible to get my requirement setup as tags link between 2 network IP applicable? I am blur as NanoPi, raspberry pi or others similar things is new for me... need others person support either you or somebody else...