DIY PLC Trainer - Arduino Uno - Phase 3 (Motor Integration)

This project simulates a basic industrial Programmable Logic Controller (PLC) system using an Arduino Uno.
It models machine states (Stopped, Running, Fault) and now controls a real 12V DC motor through a relay.

📽️ Demo Video

▶️ Watch on YouTube

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Features

✅ Start Button (Hold 3 seconds to start motor)
✅ Stop Button (Hold 3 seconds to stop motor)
✅ Fault Simulation Button (Instantly trigger fault)
✅ Motor Relay Control
✅ Visual LED Feedback
✅ Audible Buzzer Feedback
✅ Fault Recovery via EEPROM
✅ Non-blocking millis() timing for LED and buttons
✅ Clean C++ classes for LED and buzzer handling

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System Behavior

State	LED Feedback	Buzzer Feedback	Motor Relay
Stopped (OFF)	Solid Red	2 beeps (stop success)	OFF
Running	Solid Green	1 beep (start success)	ON
Holding Start/Stop	Flashing Yellow	None during hold	(Depends)
Fault Active	Fast Flashing Red	3 quick beeps	OFF
Fault Clearing	Slow Flashing Red	2 beeps when cleared	OFF

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Hardware Requirements

Component	Notes
Arduino Uno	Standard AVR
Terminal Breakout Shield	For easier wiring
NeoPixel LED	3 pins: 5V, ground and data
Piezo Buzzer	2 pins: ground and data
4-Channel Relay Module	5V type, triggered LOW
12V DC Motor	Driven by Relay Channel 4
12V 10A Power Supply	Powers entire system
3x Momentary Buttons	Start, Stop, Fault Sim
3D-Printed DIN Rail mounting parts	Optional for neatness

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Wiring Overview

Arduino Pin	Connected To
D2	Fault Simulation Button
D3	Stop Button
D4	Start Button
D7	NeoPixel LED (Signal)
D8	Piezo Buzzer
D12	Relay Channel 4 (Motor Control)
VIN/GND	Buck converter + relay + Arduino

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Setup Instructions

1. Clone the repository:

   git clone https://github.com/Beedlebub/plcTrainer_Uno.git

2. Open project in VSCode + PlatformIO.

3. Verify platformio.ini settings:

   [env:uno]
   platform = atmelavr
   board = uno
   framework = arduino
   lib_deps = 
     adafruit/Adafruit NeoPixel@^1.12.5
   monitor_speed = 115200

4. Connect hardware as per wiring diagram.

5. Upload firmware:

   • Press PlatformIO "Upload" button or use pio run --target upload.

6. Open Serial Monitor (115200 baud) to watch debug output.

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Versioning

• Phase 3.0.5
  • Updated HARDWARE_OVERVIEW.md:
    • Added 12V DC Motor entry to hardware requirements
    • Documented Relay Channel 4 (D12) controlling the motor
    • Specified Buck Converter supplying power via VIN/GND
    • Clarified NeoPixel and Piezo functions
  • General documentation cleanup for better clarity and maintainability
  • Confirmed Arduino Uno pin mappings are complete and accurate
  • Minor wording improvements in existing documentation files

Future Roadmap

• Add some analog sensors to the circuit: light and temp
• Work on an Arduino Nano RP2040 Connect hardware variant
• Port this functionality to OpenPLC
• Expand system to higher voltages (12V and eventually 24V).

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License

MIT License

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