I am currently working on a project to intergrate an Siemens 1214C PLC into my Victron system.
I have a Siemens S7 1214C (FM V3) PLC and a Cerbo of 2022.
I have a few questions about doing this. As my current attempt failed.
First of all can is the cerbo a client or a modbus server?
I tried connecting with the cerbo as a modbusclient but the PLC was not seen by the cerbo.
Can I send commands from the cerbo to the PLC via modbus?
I would like to have the PLC monitor and control multiple espects of my home. The modbus connection with the Cerbo is prefered as I would like to display some of the data of the PLC and send a few basic commands to the PLC from the control panel.
How does the cerbo display or store the recieved data? Where from can I acces this to use in node red?
As I would like to display the data on the screen I would like to use the node red dashboard to do so. But where will de read data of the PLC be stored in the cerbo? I can find a custon node with a modbus option. Is this correct?
Is there a better way of doing this?
As I would only like to display 4 intergers and send 4 boolians I was thinking of using the relay as an digital signal for now and was thinking of a way to send the information to the analog inputs.
But as the PLC can only send 0-10V or 0-20mA (or in between) I have no way of doing this I think.
Hi Manus,
My system is similar to yours. Cerbo GX via Modbus on a Siemens PLC S7-1214C (FW V4.6) and TIA Portal V18. I read all device data from Cerbo with Modbus. Pytes battery, 2x Victron Smartsolar 150/35 charge controllers, Selly 3EMPro and Hoymiles inverters with OpenDTU.
Modbus works very quickly and reliably.
I load the forecast data from the VRM portal into the PLC via Node-Red. Writing to the Cerbo (e.g. relays) is best done via Node- Red.
Itβs a bit of work when you first create it, but it works very well.
Your Modbus FB looks a little different, I suspect it is an older version.
Which TIA Portal version are you using?
Hello! If you are using an S7 you can use this node. It has a direct communication with the DB blocks in the S7. See the documentation in order to configure it, but here are some heads up:
You will need to enable access with PUT/GET communication in the PLC configuration (PLC Configuration β Protection And Security β Connection Mechanisms)
You will need to disable the optimized access in the DB (DB Config β Attributes).
You will need to reference each variable you need to access from the node-red project in the S7 Config Node.
Thank you very much. I will try to implement this.
I have FW3.0 and therefore use TIA 15.1.
What are you adress settings in siemens? Could you also share a screenshot of DB100?
What node do you use for the modbus? The same that I tried?
Do I understand correctly that the Cerbo ID is alway 100?
Since I query several Modbus participants, I assign the corresponding ID before calling the Modbus_Client FB. Once in my DB100 and in the respective instance data block of the Modbus FB.
If you only want to read in a small amount of data, querying via Node Red is of course easier.
If you want all the data from the Cerbo, I would prefer the Modbus variant.