Setting Up the Connection to the PLC

The connection between MERLIC and the Mitsubishi Electric MELSEC PLC needs to be configured in GX Works, the PLC engineering software of Mitsubishi Electric. Keep in mind that a specific version of GX Works might be required depending on the used MELSEC PLC model. Usually, MELSEC PLCs of the L and Q series must be set up in GX Works2, whereas the MELSEC PLCs of the iQ-F and iQ-R series must be set up in GX Works3.

In the following, we describe which settings are required to enable the connection between MERLIC and the PLC.

For our documentation, we make use of GX Works2 version 1.612N. If you are using GX Works3 or a different version of GX Works2, the user interface and parameter names might differ from the ones that are visible in our example images. For information on GX Works in general, its features, and how to work with GX Works to program and monitor MELSEC Series PLCs, please refer to the website of Mitsubishi Electric.

Setting the PLC Parameters for the Connection

  1. Open the PLC parameter settings of your project in GX Works2 and go to the tab for the Ethernet port settings. The following image shows an example configuration of a MELSEC PLC of series Q.

    You need to check and set the following settings:

    Settings

    Description

    IP Address

    The given IP address represents the IP address of the PLC. To ensure that MERLIC and the MELSEC Communication plug-in can be connected successfully to the PLC, the IP address that is defined for the respective parameter in the plug-in configuration must match the one that is defined in the PLC parameter settings.

    Communication Data Code

    This setting must be configured to use binary code.

    Enable online change

    The setting must be activated.

  2. Open further settings for the Ethernet port and define the desired protocol and port. To use the MELSEC Communication plug-in, you have to use the TCP as network protocol and set the system to use the MC protocol. At last, you also have to define the port that shall be used. As with the IP address, the port number defined in the PLC parameter settings must match the port number defined in the configuration of the plug-in. In our example image, the port is set to the default setting of the plug-in configuration.

For more information on the configuration of the MELSEC Communication plug-in and the parameters for the IP address and the port that need to be set accordingly, see the section Ethernet Connection Details in Configuring the Plug-in.

If all PLC parameters have been set, you can proceed with the setup of the PLC program, for example, importing the "Global Label" file, setting up the Ethernet parameters for the connection to the PLC, and implementing the PLC program. At last, you can start using the MELSEC Communication plug-in.