📖 Project Overview

This repository contains a collection of 10 practical Ladder Logic exercises developed using the OpenPLC Editor and based on the IEC 61131-3 standard.

The exercises were designed to strengthen fundamental PLC programming skills commonly used in industrial automation. Each exercise focuses on a specific control concept and includes the corresponding OpenPLC project files together with a visual screenshot of the implemented ladder diagram.

The covered topics include:

• Basic logic operations (AND / OR)
• Latching (Seal-in) circuits
• TON (On-Delay) timers
• CTU (Count Up) counters
• Rising edge detection (R_TRIG)
• Master control and safety interlocks
• Dynamic timer preset manipulation
• Sequential motor startup
• Comparison instructions (GT)

Project Objectives

• Develop practical PLC programming skills.
• Apply industrial automation concepts using Ladder Logic.
• Practice implementing IEC 61131-3 programming standards.
• Build a reusable collection of OpenPLC examples for learning and reference.

📂 Project Structure

The repository is organized into three main sections:

• images/ — Screenshots of the completed Ladder Logic exercises.
• openplc/ — OpenPLC project files for each exercise.
• README.md — Project documentation and exercise overview.

openplc-ladder-logic-exercises/
│
├── README.md
├── LICENSE
│
├── images/
│   ├── exercise-01-and-logic.jpg
│   ├── exercise-02-or-logic.jpg
│   ├── exercise-03-latching-circuit.jpg
│   ├── exercise-04-ton-timer.jpg
│   ├── exercise-05-ctu-counter.jpg
│   ├── exercise-06-rising-edge-toggle.jpg
│   ├── exercise-07-master-control-switch.jpg
│   ├── exercise-08-dynamic-timer-presets.jpg
│   ├── exercise-09-sequential-motor-startup.jpg
│   └── exercise-10-comparison-logic.jpg
│
└── openplc/
    ├── exercise-01-and-logic/
    ├── exercise-02-or-logic/
    ├── exercise-03-latching-circuit/
    ├── exercise-04-ton-timer/
    ├── exercise-05-ctu-counter/
    ├── exercise-06-rising-edge-toggle/
    ├── exercise-07-master-control-switch/
    ├── exercise-08-dynamic-timer-presets/
    ├── exercise-09-sequential-motor-startup/
    └── exercise-10-comparison-logic/

📝 Exercise List

#	Exercise	Industrial Concept	OpenPLC Project
01	AND Logic	Safety Interlock using series contacts	exercise-01-and-logic
02	OR Logic	Remote motor control using parallel branches	exercise-02-or-logic
03	Latching Circuit	Start/Stop seal-in control	exercise-03-latching-circuit
04	TON Timer	Delayed machine startup	exercise-04-ton-timer
05	CTU Counter	Conveyor box counting system	exercise-05-ctu-counter
06	Rising Edge Toggle	Toggle control using R_TRIG	exercise-06-rising-edge-toggle
07	Master Control Switch	Safety interlock with NC master stop	exercise-07-master-control-switch
08	Dynamic Timer Presets	Timer preset selection using MOVE	exercise-08-dynamic-timer-presets
09	Sequential Motor Startup	Time-delayed motor sequencing	exercise-09-sequential-motor-startup
10	Comparison Logic	Inventory monitoring using GT comparison	exercise-10-comparison-logic

📷 Exercise Gallery

Each exercise includes its corresponding OpenPLC project and a screenshot of the implemented Ladder Logic.

Exercise	Preview
Exercise 01 – AND Logic (Safety Interlock)
Exercise 02 – OR Logic (Remote Control)
Exercise 03 – Latching Circuit
Exercise 04 – TON Timer
Exercise 05 – CTU Counter
Exercise 06 – Rising Edge Toggle
Exercise 07 – Master Control Switch
Exercise 08 – Dynamic Timer Presets
Exercise 09 – Sequential Motor Startup
Exercise 10 – Comparison Logic

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🧠 Skills Demonstrated

Through these exercises, the following industrial automation and PLC programming skills are demonstrated:

• ✅ IEC 61131-3 Ladder Logic Programming
• ✅ OpenPLC Simulator Development
• ✅ Boolean Logic (AND / OR)
• ✅ Latching (Seal-in) Circuits
• ✅ TON (On-Delay) Timers
• ✅ CTU (Count Up) Counters
• ✅ Rising Edge Detection (R_TRIG)
• ✅ Toggle Circuit Design
• ✅ Master Control (Emergency Stop) Logic
• ✅ Dynamic Timer Presets using Variables
• ✅ Sequential Motor Control
• ✅ Comparison Instructions (Greater Than)
• ✅ Industrial Control Logic Design
• ✅ PLC Troubleshooting and Testing
• ✅ Automation System Documentation

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⚙️ Technologies Used

Category	Technology
PLC Simulator	OpenPLC Simulator
Programming Standard	IEC 61131-3
PLC Language	Ladder Logic (LD)
Development Environment	OpenPLC Editor
Operating System	Windows
Documentation	Markdown
Version Control	Git & GitHub

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🚀 How to Run the Exercises

1. Install OpenPLC Editor or OpenPLC Simulator.

2. Clone this repository or download it as a ZIP file.

3. Open the desired exercise folder from:

   openplc/
   

4. Load the project into OpenPLC.

5. Compile and run the Ladder Logic program.

6. Compare the implementation with the corresponding screenshot in the images/ folder.

Note: Each exercise is independent and can be executed separately without relying on other exercises.