PLC Steps – Your Guide to Industrial Automation

Note: To follow along with this example, you will need to run a PLC simulation and establish communication with WinCC 7.5. For a detailed step-by-step guide on setting up a PLC simulation in TIA Portal V16 and connecting it to WinCC, refer to our dedicated tutorial:

This tutorial covers everything from creating the PLC project and defining variables to configuring the communication between the PLC and WinCC, ensuring you can test your HMI tags in a fully simulated environment.

In this tutorial, we will guide you step by step on how to create HMI tags in WinCC 7.5 and connect them to your PLC. By the end of this tutorial, you will understand how to define global variables, set up tag properties, and establish the connection between your HMI and PLC.

Step 1: Create a Global DB in the PLC

First, we create a Global DB in the PLC project. In the Properties → Attributes section, make sure to deselect “Optimized block access”. This is important because optimized blocks do not allow direct access to individual variables from the HMI.

Properties → Attributes section, make sure to deselect “Optimized block access

Inside the Global DB, create two Boolean variables: On and Off. Once created, check that each variable now has a value in the Offset column — this ensures that the PLC assigns a memory location for each variable, which is required for HMI communication.

Verify that Variables has Offset Value

Step 2: Open Tag Management in WinCC

Open your WinCC project and navigate to Tag Management.
Within the Connection section, create a new group to organize your HMI tags. Grouping tags makes your project cleaner and easier to manage, especially as the number of tags grows.

Add New Group On Tag Management

Step 3: Define Each HMI Tag

For every HMI tag you want to use, define the following:

1. HMI Tag Name:
   • The name used to reference the tag inside WinCC screens, scripts, and alarms.
2. Data Type:
   • Choose the appropriate type:
     • Boolean → Binary
     • Integer → Int/UInt (Signed/Unsigned)
     • Real → Floating-point number
3. Address:
   • This is the PLC memory address associated with the HMI tag. It is crucial to link the tag to the correct PLC variable to ensure proper communication between HMI and PLC.

Once these steps are completed, your HMI tags are ready and connected to the PLC, allowing you to use them in screens, scripts, alarms, and other WinCC features.

HMI Tags Definition

---

If you found this helpful, please consider supporting with a small donation. Thank you!