Connecting a Tag to a PLC

Introduction

Hello and welcome to a new quick start guide on how to best use Movicon.NExT™.
In this technote you will learn how to connect a Movicon.NExT project tag to programmable logic controller, commonly known as the PLC, by means of using a driver.

Connection Methods

To establish a connection between a tag and a PLC, you'll need either a PLC or a PLC simulator, along with a Movicon.NExT project that has a configured driver and at least one defined tag.
There are two different methods which you can use to connect a tag to a PLC or a generic field device:

By defining the Physical I/O Address: you can define an address in the tag's properties to connect to the memory area of the PLC in question in order to connect it to the field device.
By importing PLC's tags: you can import the tags defined on the PLC in Movicon.NExT using the Import Tags tool which is made available by the Driver. You can import tags from a file generated within the PLC development environment or by directly connecting to the field device by using the driver.

First Method

Let's go through the first method.
To test the connection of a tag to a PLC in this scenario, we will use ModRS_Sim, which is a PLC simulator that use the Modbus TCP protocol, along with a new Movicon.NExT project.
Start the Modbus simulator by double clicking the simulator icon.
Open Movicon.NExT in design mode and create a new project:

Open the I/O Data Server located in the project resource tree in the Project Explorer Window.
Select the I/O Driver tab to add the Modbus TCP-IP driver.
Once the I/O Driver has opened, right click on the workspace and select the Add New Driver option from the menu that appears.
Select the Modbus TCP-IP driver from this list that shows. Click on the arrow to go ahead and configure it.
Leave all settings set for default in the Driver's General Settings window and proceed by clicking the arrow to go ahead to the next step.
Enter your PLC's IP address in the driver's configuration window. In our example, we will use the local loopback IP address which is 127.0.0.1. Leave the other properties set for default and go to the next step.
Leave all the driver's Station's properties in the configuration window set for default.
To conclude the configuration procedure, click on Finish to insert the driver on the driver list.

Now we will create a tag to connect to the PLC simulator:

Go to the Tag List by selecting appropriate I/O Data Server tab.
Right click on the workspace and select the Add New Tag from the menu that appears.
Configure the tag using the properties window in the following way:

Name: MbtcpTag

- Model Type: Variable
- Data Type: Int16
Confirm the changes by clicking on the Accept Changes icon on the tag's property window toolbar at the top.
Search for the Physical I/O Address option in the tag's Execution property group and click on the three dots within brackets on the far right to access the tag's PLC address configuration.
In the popup that appears, leave everything set for default and only select the station from the combobox.
Click Ok to confirm.

When you have finished configuring the tag, save the project by clicking on the Save All icon on the Movicon.NExT editor's toolbar at the top.

Startup the project's Server side only by clicking the Start Server icon on the Movicon.NExT Editor's top toolbar.
Click on Tags in the OPC UA Browser window, which opens when starting up the Movicon.NExT Server, to monitor the previously created MbtcpTag tag.
Change the value of the MbtcpTag tag shown in the value column with an integer as pleased by double clicking on the table's cell. Press enter to send the entered value to the simulator and stored.
By opening the simulator and going to the Holding Registers section, you will see the value written in Movicon.NExT at the Modbus simulator's 40001 address. Of course, the reverse process also holds true.

Second method

Lets now look at the second method to import a tag directly from a field device.
In this example, we will use the OPC UA Prosys simulator.
Once the simulator has been installed, double click its icon to open it.
When the simulator has started up, go back to the previously used Movicon.NExT project.
We will use the same procedure used for the Modbus TCP-IP driver to configure the OPC UA Client driver. Therefore:

Open the I/O Data Server located in the project resource tree in the Project Explorer Window.
Select the I/O Driver tab to add the OPC UA Client driver.
Once the I/O Driver has opened, right click on the workspace and select the Add New Driver option from the menu that appears.
Select the OPC UA Client driver from this list that shows. Click on the arrow to go ahead and configure it.
Leave all settings set for default in the Driver's General Settings window and proceed by clicking the arrow to go ahead to the next step.
Leave all the values set for default in the Driver's Channel properties and go to the next step.
Leave all the driver's Station's properties in the configuration window set for default.
To conclude the configuration procedure, click on Finish to insert the driver on the driver list.

Now that the driver has been added, we shall now import the items configured in the OPC UA Prosys simulator. In order to do this, we will start with the driver list:

Select and right click the OPC UA Client driver.
Select the Import Tags option from the menu that appears.
Click the Browse Server tab in the window that appears. In this section we can add an endpoint and browse its items.
Click on Add End Point and insert the OPC UA Prosys simulator's Endpoint URL which is found in the OPC UA Servers homepage.
Enter the OPC address and click the OK button to confirm.
If there are no errors, the opc.tcp connection without security should appear in the Network Discovery pane. Double click on the newly added endpoint.
Browse the OPC UA Server until you reach the Simulation folder containing the Counter and Constant items.
Select the Counter and Constant item and click the Import Tags button.

As soon as this procedure is completed, the Counter and Constant items will be inserted on the list of tags on the Tags List tab.
Select the tag that has just been imported on the list and note that the tag's Physical I/O Address is configured independently in accordance with the OPC UA Client property.

Save the project by clicking on the Save All icon on the Movicon.NExT editor's toolbar at the top.

As before, run the project's server side by clicking on the Start Server button on the Movicon.NExT Editor's top toolbar.
Click on Tags in the OPC UA Browser window that opens when starting up the Movicon.NExT Server and expand Station0 and then Simulation to monitor the previously imported Counter and Constant tags.
Double click on the table cell to change the value of the Constant tag shown in the value column with any integer value. Press enter, to store and send the written value to the simulator.
Open the OPC UA simulator and then go to the Objects tab and expand the Simulation folder and select the Constant item. Note that in its properties, the Value is equal to the one set in the Movicon.NExT's OPC UA Browser window.