How to Transfer Data from Modbus to Allen Bradley

Open Automation Software can be used to transfer data from a Modbus device to an Allen Bradley device locally or over a network. This guide walks you through downloading and installing OAS, configuring a Modbus connector, an Allen Bradley connector and one tag for each.

This guide uses the Data Route feature of OAS to transfer a Tag's value to another Tag's value using the Tag-to-Tag method.

For this guide on how to transfer data between a Modbus device and an Allen Bradley device you will need:

• A Modbus device or simulator connected to your workstation
• An Allen Bradley device connected to your workstation

1 - Download and Install OAS

If you have not already done so, you will need to download and install the OAS platform.

Fully functional trial versions of the software are available for Windows, Windows IoT Core, Linux, Raspberry Pi and Docker on our downloads page.

On Windows, run the downloaded setup.exe file to install the Open Automation Software platform. For a default installation, Agree to the End User License Agreement and then click the Next button on each of the installation steps until it has completed.

If you'd like to customize your installation or learn more, use the following instructions:

• Windows Installation
• Linux Installation
• Raspberry Pi Installation
• Docker Installation

The OAS Service Control application will appear when the installation finishes on Windows.

Click on each START SERVICE button to start each of the three OAS services.

2 - Configure OAS

Web Configuration Application

Configuration of the OAS server is performed from the built-in Web Configuration Application. This is the main application for accessing any settings within the OAS server and is completely self-contained within the server.

You can reach this by opening your browser to:

http://<your server>:58725/app/config

If you are browsing from the OAS machine itself, you can use localhost, otherwise use the IP address of the machine. You will also need to ensure port 58725 is open on both the client and the server or you may not be able to reach the application.

On a new installation the OAS engine has no accounts yet, so the first screen you see is Create Admin Account. Once the administrator account exists that screen is not shown again, and browsing to the application displays the sign in screen instead.

1. Enter a name for the administrator in the Admin user name field. Typically you would use admin, but you can use whatever name you choose.

2. Enter a password in the Password field, then enter the same password again in the Confirm password field.

3. Click on the Create admin & sign in button. The account is created and you are signed in to the engine.

To sign in from then on, enter the Network node of the OAS engine, then the Username and Password of your account, and click on the Sign in button.

Legacy Configuration Application

1. From your operating system start menu, open the Configure OAS application.

2. Select the Configure > Tags screen.

   Important

   If this is the first time you have installed OAS, the AdminCreate utility will run when you select a screen in the Configure menu. This will ask you to create a username and password for the admin user. This user will have full permissions in the OAS platform.

   For further information see Getting Started - Security.

3. If this is the first time you are logging in, you will see the AdminCreate utility. Follow the prompts to set up your admin account. Otherwise, select the Log In menu button and provide the Network Node, username and password.

   

   

3 - Configure Modbus Data Source

In the following steps you will create and configure a Modbus Connector to act as a data source. This will use a Master connection type and an Ethernet TCP connection. It assumes that your device is using the default port 502.

1. Select Drivers in the sidebar.

2. Click + Add, enter a meaningful Driver Interface Name to give this driver interface instance a unique name, and click Create. Once created, the driver interface name should appear in the list of drivers.

3. Ensure the following parameters are configured:

   • Driver: Modbus
   • Type: Master
   • Connection: Ethernet
   • Ethernet Type: TCP
   • Port Number: 502

4. Specify the device IP in the IP Address field.

   

5. Turn on Enable and click on the Apply changes button. The driver interface is not active until it is enabled and the changes are applied.

   

4 - Add Data Source Tag

In this section you will create a Tag to represent your data point in the field (for example a temperature sensor). This can then be transferred your desired destination.

1. In the sidebar menu, select Tags.

   

2. If you want to add a Tag to the root Tags group make sure another tag at the root is selected. Click the [+] button and select Add Tag.

   

   If you want to add a Tag to a Tag Group, select the Tag Group first and then click on the [+] button. Alternatively, you can right click on a Tag Group and select Add Tag.

   You can also add Tag Groups by clicking the [+] and selecting Add Group.

3. Provide a Tag Name such as TemperatureSensor and click the Create button.

   

5 - Assign Modbus as Tag Data Source

You will now set the Tag's data source to the Modbus driver interface that you created previously to act as a data source.

1. Select the Tag that will be associated with the Modbus data source.

   

2. Set the Data Source to Modbus.

3. Set the Select Driver Interface drop-down to the ModbusSource interface created previously.

4. Configure the Modbus parameters accordingly based on your device requirements.

   • Device Address: The Modbus station number [default: 1]
   • Memory Type: The Modbus data model table type [Coil Status, Input Status, Input Register, Holding Register]
   • Address: The register to read/write based on the address offset
   • Modbus Data Type: The Input and Holding Register data type
   • Zero Based Address: Whether the Address starts at 0 or 1 [default: true]
   • Word Swap & Byte Swap: Adjust as required for your controller type [default: false]

5. Set the polling rate in seconds by setting the Polling Rate property [default: 1 second].

   

6. Click on the Apply changes button to apply the changes.

7. Check that the quality status is Good and the Tag value is as expected.

   

6 - Configure Allen Bradley Data Destination

In the following steps you will create and configure an Allen Bradley Connector using an AB Logix driver type to act as a data destination. This guide assumes that you have a Micro800 series controller connected to the same network as the OAS instance.

1. Select Drivers in the sidebar.

2. Click + Add, enter a meaningful Driver Interface Name to give this driver interface instance a unique name, and click Create. Once created, the driver interface name should appear in the list of drivers.

3. Ensure the following parameters are configured:

   • Driver: AB Logix
   • IP Address: Your controller IP address
   • Processor Type: Micro800

   

4. Turn on Enable and click on the Apply changes button. The driver interface is not active until it is enabled and the changes are applied.

   

7 - Add Data Destination Tag

In this section you will create a Tag to represent a data point that you want to write to.

1. Select Tags in the sidebar.

2. If you want to add a Tag at the root of the tag list, make sure no Tag Group is selected and click on the + button, then choose Add tag.

   

   If you want to add a Tag to a Tag Group, select the Tag Group first and then click on the + button and choose Add tag here.

   You can also add Tag Groups by choosing Add group.

3. Provide a Tag Name such as TemperatureOutput and click the Create button.

   

8 - Assign AB Logix as Tag Data Destination

You will now set the Tag's data source to the AB Logix driver interface that you created previously to act as a data destination.

1. Select the Tag that will be associated with the AB Logix destination.

   

2. Set the Data Source to AB Logix.

3. Set the Select Driver Interface drop-down to the Micro820-Destination interface created previously.

4. Click on the Browse… button next to the Address field to open the Browse for AB Address window.

   

5. The window lists the programs the driver interface can reach on the controller. Choose the program or controller, select the variable you want, and click Use this address.

   

6. Click on the Apply changes button to apply the changes.

7. Check that the quality status is Good and the Tag value is as expected. If the PLC does not hold any value in the given register then the value will remain zero.

9 - Configure Tag-To-Tag Data Route

In this section you will configure the Target of the source Tag to be the destination Tag value. This means whenever the source Tag value is updated, the destination Tag value will also be updated. This will cause a write operation on any associated driver if it is supported.

1. Select the source data Tag.

   

2. Scroll down to the Target section.

   

3. Enable the Enable Write to Target option.

   

4. Click on the Browse… button, select the destination Tag and click on the Use this tag button.

   

5. Optionally, configure the Deadband property or enable Write Continuously to configure a continuous writing frequency.

   

6. Click on the Apply changes button to apply the configuration.

7. To verify that your data transfer is working correctly, select the destination Tag and check that the Tag value matches the Tag value of the source Tag.

   

   You should also verify that the Tag value has been written to your destination device. Depending on your configuration in step 5 above, this destination value should be updated whenever the source value changes or at the given frequency.

10 - Save Changes

Once you have successfully configured your OAS instances, make sure you save your configuration.

On each configuration page that has a Save button, click on it.

If this is the first time you are saving the configuration, or if you are changing the name of the configuration file, OAS will ask you if you want to change the default configuration file.

If you select Yes then OAS will make this configuration file the default and if the OAS service is restarted then this file will be loaded on start-up.

If you select No then OAS will still save your configuration file, but it will not be the default file that is loaded on start-up.