Project Hub /IoT & Connected Devices/Smart Home & Building Automation/IOT-based Light Dimmer and Speed Controller

Intermediate

ARDUINO

Project Specific

3 – 6 Hours

Partial Kit

IOT-based Light Dimmer and Speed Controller

Build a wireless IoT device to control AC appliance speed and light brightness via a smartphone UI dashboard.

Originally published on ElectronicsForU

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

NodeMCU ESP8266 WIFI development board based on CP2102 Rs. 660.00
10pcs 5mm RED Diffused Light Emitting Diodes - LEDs Set Rs. 39.00
LDR Light Sensor Module Rs. 49.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

We don't carry yet: Solid State Relay / Triac / Dimmer

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How It Works

The IoT-based Light Dimmer and Speed Controller bridges wireless networking with power electronics to let you adjust AC appliances remotely. At the heart of the system is the ESP-12F module, a Wi-Fi-enabled microcontroller that connects to your local wireless network. Through a compatible smartphone or computer utilizing the ESP dashboard library, you can send commands over the internet directly to the microcontroller. The ESP-12F processes these incoming wireless signals and translates them into control outputs. To interact with high-voltage alternating current loads, the low-voltage DC logic of the microcontroller must interface safely with an AC triac circuit. The triac acts as an electronic switch that regulates the power delivered to the connected appliance by controlling the phase angle of the AC waveform, effectively adjusting light brightness or motor speed. Additionally, the circuit features an LED for status indication and an LDR (Light Dependent Resistor) which can provide ambient light feedback to the system. Powering the logic side of this setup is a 3.3V battery adapter, ensuring the ESP-12F receives stable operating voltage while completely isolated from the dangerous mains voltage flowing through the triac and AC load.

Why Build This

Gain hands-on experience designing modern smart home automation systems by creating a custom smartphone-controlled dimmer for lights and fans.

Understand the practical challenges of bridging low-voltage microcontroller logic with high-voltage AC power circuitry safely.

Learn how to program an ESP-12F module using the Arduino IDE to serve a web-based dashboard over Wi-Fi.

Real-World Application

Wireless home automation for dimming lights and controlling fan speeds, as well as industrial applications like wirelessly controlling AC appliances, elevators, and conveyor belts.

Skills You'll Learn

Wi-Fi microcontroller programming

AC phase control with triacs

sensor integration with LDRs

web dashboard configuration

low-voltage to high-voltage electrical isolation

Safety Precautions

Exercise extreme caution when working with high-voltage AC circuits and mains power. Ensure proper electrical isolation between low-voltage DC logic and high-voltage AC components.

Technology Tags

IOT

ESP12F

ESP32

ARDUINO IDE

WI-FI

HOME AUTOMATION

SMART APPLIANCE CONTROL

Frequently Asked Questions

Can I plug a standard 120V or 230V AC appliance directly into this circuit?

Yes, the AC triac circuit is designed to control mains-powered appliances, but you must exercise extreme caution and ensure proper wiring insulation to prevent electric shock.

Do I need an internet connection to control the dimmer?

The ESP-12F module connects via Wi-Fi, typically requiring a local wireless network for the smartphone or computer dashboard to communicate with the microcontroller.

What is the purpose of the 3.3V battery adapter?

The 3.3V adapter powers the low-voltage DC logic of the ESP-12F microcontroller, keeping it electrically separated from the high-voltage AC circuit.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

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