Book Image

Mastering PLC Programming

By : Mason White
Book Image

Mastering PLC Programming

By: Mason White

Overview of this book

Object-oriented programming (OOP) is a new feature of PLC programming that has taken the automation world by storm. This book provides you with the necessary skills to succeed in the modern automation programming environment. The book is designed in a way to take you through advanced topics such as OOP design, SOLID programming, the software development lifecycle (SDLC), library design, HMI development, general software engineering practices, and more. To hone your programming skills, each chapter has a simulated real-world project that’ll enable you to apply the skills you’ve learned. In all, this book not only covers complex PLC programming topics, but it also removes the financial barrier that comes with most books as all examples utilize free software. This means that to follow along, you DO NOT need to purchase any PLC hardware or software. By the end of this PLC book, you will have what it takes to create long-lasting codebases for any modern automation project.
Table of Contents (25 chapters)
1
Part 1 – An Introduction to Advanced PLC Programming
6
Part 2 – Modularity and Objects
10
Part 3 – Software Engineering for PLCs
14
Part 4 – HMIs and Alarms
19
Part 5 – Final Project and Thoughts

HMI design

The first thing we should do is lay out our HMI. Based on the requirements, we are going to need the following at the minimum:

  • An alarm table
  • A series of inputs to allow the user to input the temperature of the oven
  • A gauge to show the current temperature of the oven
  • A power switch and LED for the oven
  • An LED for the following:
    • Oven ramping up to temperature
    • Oven at temperature
  • An alarm acknowledgment button

With the requirements, we can lay out our HMI to look like the following screenshot:

Figure 15.1 – Oven HMI

Figure 15.1 – Oven HMI

This is a simple HMI layout for our project. We have a simple Power button in the lower left-hand corner with a ramp-up and target temperature spinner above it. In the center of the screen, we have an alarm table for our alarm readout as well as three LEDs to indicate that the oven is on, another LED to indicate that the temperature of the oven is human-safe, and finally, an LED to indicate that...