Modbus TCP

[Yahya]

Good day all,

i need advice for Modbus TCP configuration on mitsubishi iQ-R PLC.

I have 4 PLC iQ-R R08P CPUs with the configuration as shown in the picture. PLC 1,2,3 communicate with the master PLC using simple CPU Read/Write communication. from the master PLC, all tags on PLC 1,2,3 are configured to be modbus TCP with the RJ71EN71 module.

The problem I am facing is how do I get the communication status of each PLC to the master PLC with simple CPU communication. I want to display the communication results of each PLC as a tag on modbus TCP.

Thank you very much

[Gambit]

Look like you have all the communication running right ? So you question is where you can find the status of simple PLC comms ?

 

[pturmel]

Since the master PLC is actually a modbus slave, and you want that slave to also respond to your monitoring, you will likely need to write a regularly changing value from each slave PLC to separate registers in the master PLC (heartbeat signals).  Then have code in the master PLC that will time out if a given slave's heartbeat stops changing.  Place the booleans for that status in other modbus addresses that the monitoring system can see.  (Or, perhaps, have the monitoring system watch the same heartbeat values.)

[Yahya]

6 hours ago, Gambit said:

Look like you have all the communication running right ? So you question is where you can find the status of simple PLC comms ?

 

 

That's right, I want to know the communication status of the master PLC with PLC 1,2,3. is that possible?

[Yahya]

1 hour ago, pturmel said:

Since the master PLC is actually a modbus slave, and you want that slave to also respond to your monitoring, you will likely need to write a regularly changing value from each slave PLC to separate registers in the master PLC (heartbeat signals).  Then have code in the master PLC that will time out if a given slave's heartbeat stops changing.  Place the booleans for that status in other modbus addresses that the monitoring system can see.  (Or, perhaps, have the monitoring system watch the same heartbeat values.)

Does the heartbeat function have to be created manually? Or is there a separate library from Mitsubishi Electric?

[Gambit]

15 minutes ago, Yahya said:

 

That's right, I want to know the communication status of the master PLC with PLC 1,2,3. is that possible?

Have a look op PAGE ID : SH081257ENG-8C2 of the e-manual viewer. Checking the simple CPU communication status.

Edited April 23, 2024 by Gambit

[Yahya]

1 hour ago, Gambit said:

Have a look op PAGE ID : SH081257ENG-8C2 of the e-manual viewer. Checking the simple CPU communication status.

I can't find the document in the e-manual

 

Edited April 23, 2024 by Yahya

[pturmel]

6 hours ago, Yahya said:

heartbeat function have to be created manually?

I would make it precisely to fit my needs.  Maybe Mitsu has something built-in, but I'm not a Mitsu expert.

[Yahya]

7 hours ago, pturmel said:

I would make it precisely to fit my needs.  Maybe Mitsu has something built-in, but I'm not a Mitsu expert.

Thank you for advice Sir

[Gambit]

15 hours ago, Yahya said:

I can't find the document in the e-manual

 

That's not how you search. Download the latest manuals if needed. Then patse  SH081257ENG-8C2 in the search bar but change the [ALL] button into

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See attached doc

e-Manual Viewer Page ID and KB Doc ID Guide.PDF

Edited April 24, 2024 by Gambit

[Yahya]

12 hours ago, Gambit said:

That's not how you search. Download the latest manuals if needed. Then patse  SH081257ENG-8C2 in the search bar but change the [ALL] button into

---

See attached doc

e-Manual Viewer Page ID and KB Doc ID Guide.PDF

thank you, my problem has been resolved