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ESP32 Roll Laminator Controller

Русская версия

Modern replacement controller for inexpensive roll laminators based on ESP32-C3 and ESPHome.

The project replaces the original controller board with a fully programmable, modular, and repairable solution built from standard components.

Project Goals

• High reliability
• Electrical safety
• Easy maintenance and repair
• Use of widely available components
• Complete separation of high-voltage and low-voltage circuits
• Home Assistant integration
• Open-source hardware and firmware

Current Status

Version: 1.0

✔ Hardware completed

✔ ESPHome firmware completed

✔ Control algorithms completed

✔ Preliminary temperature calibration completed

⏳ Fine temperature calibration and long-term testing remain.

Main Features

• Heater temperature control
• Motor forward / reverse control
• Temperature adjustment using a potentiometer
• Analog temperature meter support
• Two status LEDs (PREHEAT / WORK)
• NTC 100k B4300 temperature sensor
• Home Assistant integration through ESPHome
• Simple modular architecture
• Standard relay module support
• Easy assembly on perfboard

Safety

The controller was designed with electrical safety as one of its primary goals.

Unlike the original controller board, all high-voltage (220 VAC) circuitry has been removed from the control electronics.

The ESP32 board, switches, potentiometer, LEDs, and temperature sensor operate exclusively from 3.3 V / 5 V.

The only part connected to mains voltage is the external 4-channel relay module, which switches:

• Heater
• Motor power
• Motor direction

This architecture significantly improves safety, simplifies debugging, and makes future repairs much easier.

Hardware

• ESP32-C3 LuatOS Core

Temperature sensor:

• Glass NTC 100k B4300

Voltage regulator:

• AMS1117-3.3

Relay module:#

• Standard 4-channel relay board
• Active LOW inputs

GPIO Mapping

Unused GPIO:

• GPIO8
• GPIO9
• GPIO12
• GPIO13
• GPIO18
• GPIO19

Relay Module

The project uses a standard 4-channel Active LOW relay module.

Logic:

• GPIO LOW → Relay ON
• GPIO HIGH → Relay OFF

ESPHome configuration:

• inverted: true
• restore_mode: ALWAYS_OFF

This guarantees that all relays remain OFF immediately after power-up or reset.

Repository Structure

Firmware/
    ESPHome YAML

Hardware/
    Schematics
    PCB
    KiCad project

docs/
    Technical specification
    Calibration notes

Images/
    Photos
    Schematics

Requirements

• ESPHome
• Home Assistant (optional)
• ESP32-C3
• 5V power supply
• Standard 4-channel relay module

Future Improvements

• Final temperature calibration
• Long-term reliability testing
• PCB revision
• Optional WS2812 status indicator
• Additional Home Assistant entities

License

This project is released under the MIT License.

Feel free to use, modify and improve it.