CODESYS 3.5 - PLC Programming With Structures - Lesson 22 - HMI / Visualisation Walkthrough

🔹This course is from 2023 and is now free. You can still access it ad free at https://liambee.me if you become a member or purchase the course.

🔹Download all course materials for free here:
https://liambee.me/codesys-structured...

In this lesson we move into the visual side of the project and look at how structured data is passed directly into visualisation elements. Although this example uses Codesys, the principles apply to most SCADA and HMI systems. The key idea is that every faceplate or widget is driven by a complete structure rather than many individual tags. Once you see it in practice, the benefits become obvious.

We start by exploring how the visual environment in this project is organised. The base screen is made up of three sections, a top navigation bar, a central display area and a bottom bar with a live alarm summary and an acknowledge all button. From there we load individual screens such as the alarm page, the main overview and the simulation page. These screens contain the actual faceplates that bind to your structured data.

When we open the overview page, we can see how each device is linked. A valve graphic receives its entire DUT QT Valve structure as a single reference. A pump faceplate receives the pump structure and a few display options such as orientation. A tank graphic receives its structure and additional visual settings. Dials for analog devices also work the same way. Once the structure is passed in, the faceplate has access to every value it needs without requiring dozens of separate bindings.

We look at quick plates too. These are pop up faceplates that appear when you click on an asset. They allow you to view and manipulate settings such as auto mode, hand mode, open and close requests. Again, each quick plate receives just one structure reference plus a simple control flag to show or hide it.

Next, we run the system in simulation to see how everything connects. Once the simulation mode is enabled and auto feedback is turned on, the valves, pumps and analog instruments begin behaving correctly because the simulation structures feed the same process structures that the rest of the program uses. This means the visualisation behaves exactly the same way whether the underlying data is coming from the real plant or from the simulation system.

We step through a few examples. Valves update correctly, tank levels rise and fall, alarms appear in both the alarm page and the live summary bar, and acknowledging and resetting alarms clears them from the visualisation immediately. All of this works because each faceplate only ever looks at its own structure. It does not care where the values originated.

The important takeaway in this lesson is that the visual system is not made up of hundreds of loosely connected tags. It is made up of structured objects. Updating a structure automatically updates every faceplate that references it. If you later expand a structure with more information, you instantly have access to that new data in every visual element without redesigning anything.
By the end of this lesson, you will understand how to build a clean, scalable and maintainable HMI environment that mirrors the structured approach used in the PLC. Make sure to download the example project and click through the screens yourself. Seeing the structure driven visuals in action will make the entire concept much clearer.

#AlwaysLearning #Automation #Codesys #PLC #HMI