remote modbus vfd control

Hi, I'm from Brasil. I need to control a vfd remotely by MODBUS rs485 RTU over ethernet .For that,
I'm using a two controllers called FENTUM II made in Brasil, an IHM Delta B03S211and a danfoss VFD. Notice, when I connect the IHM directly to VFD, Ican control the VFD.


If anyone can help me, I would appreciate it.


Controller Manual ===> https://drive.google.com/open?id=1-Sb85S4XOwmIqMBOnFxvFSqEwwiCvnZW



Controller Programmer Manual ===> https://drive.google.com/open?id=1fTQIgcV4iCOKKibZoDg8K3BqZ-422KUg

You might want to re-ask your question, you may have everyone confused because you or either working with Modbus rs485 rtu or Modbus TCP.

I don't think what you ask makes any sense. Because you state
"Modbus rs485 Rtu over Ethernet."

Forgive me if I am incorrect.

This controller have an ethernet port and a rs485 port.



both ethernet port are conected by the internet link. And both vfd and the hmi are conected by rs485 port understood?

OK, so both PLC's are connected together by "Ethernet", and the VFD's and HMI's are connected together with rs485 coming from the PLC?

Let me try to explain the basic setup. If both PLC's need to talk to each other you will use Modbus TCP(because they are not connected together by the rs485), but for the VFD's and HMI's you will use Modbus 485 Rtu(because they are not connected with ethernet).

Now the Modbus commands will be the same for both.

The programmer will have to have the Modbus address parameters for all 3 devices and if this can't be done this project can't be done

I'm just trying to help you get your questions together so people who can help, will respond to your needs.



I also want to say this is a "complicated project".

The both plc are communicating. I can control any output of the slave controller. But a need to control the vfd through their rs485 port.
Did you see the product manual?

David was trying to establish exactly what you are trying to accomplish because that was not clear from your first post, and to me, that still is not clear. The manuals can provide details for tactics, but your overall goal, what you are attempting to do (who controls what and when) is still not clear.

What I read up to this point:

1. You have two PLC controllers, an IHC and a Fentum. Both PLC controllers communicate with one another: both plc are communicating.

2. The IHM PLC can communicate directly to the VFD.
when I connect the IHM directly to VFD, Ican control the VFD.

3. If both the IHM and the Fentum PLC's communicate with one another why not use the IHM to communicate to the VFD and the Fentrum communicates through the IHM?

If you do that, the IHM needs

- some 'logic rules' to determine if whatever teh Fentrum wants is legitimate and valid.

- the ability to store and forward Modbus requests from the Fentrum

If this is not case, correct me.
If your goal is something else, tell us.

Because the ihm and the inverter are not in the same place. if they were I would not need the plcs. The ihm is in the city and the investor is there in the rural area where the water pump is.

Look a ilustrate of the problem

Perhaps the situation will be clearer now.

Some pictures of the ihm setup and modbus addresses

Some pictures of ihm setup

Good illustration. That helps enormously.



But someone else will have to help you on this, I don't do internet commmunications that involve gateways and routers, but I suspect that it involves running a VPN connection.

As I said before, I can trigger any slave output through the network. But I need to write to port rs485 to command the vfd. I can send you an example of the program if you want

This is easiest done using 2 separate 3G/4G-modems and talk to a carrier that have APN-services and/or VPN-services. Insys have a well working service, ”Connectivity Service”.
Configure send-recieve areas and off you go!


Once that is solved, the fun part begins. ��

valdir said:

As I said before, I can trigger any slave output through the network. But I need to write to port rs485 to command the vfd. I can send you an example of the program if you want

Click to expand...

So all you need help with is modbus communication between the PLC and VFD and all the ethernet communication has been already sorted out. Awesome. Your google drive links don't work for me how about you post the part number of both the PLC and VFD and hopefully the manuals for both are available online.