Smart Home Automation with Miniature CO₂ Module T6713 and BLE Multi-Device Control

Introduction

Modern smart homes are no longer just about convenience; they are about health, energy efficiency, and automation intelligence. Among the many parameters that define a healthy indoor environment, carbon dioxide (CO₂) levels play a vital role. Your body naturally wants to expel CO₂, which means you should avoid high concentrations of it in the air you breathe.

The Amphenol Advanced Sensors Telaire T6713 is a miniature, energy-efficient CO₂ sensor module designed for precision indoor air quality monitoring. When integrated with a Bluetooth Low Energy (BLE) automation system, it becomes the brain of a fully automated environment — controlling ventilation, lighting, and appliances based on air quality, occupancy, and user preferences.

Core of the System: Telaire T6713 Miniature CO₂ Module

The T6713 module is a factory-calibrated NDIR (Non-Dispersive Infrared) CO₂ sensor that measures concentrations up to 5000 parts per million (ppm) with high accuracy.

Key Features:

• Size: 30 mm × 15.6 mm × 8.6 mm — perfect for embedding in compact control units.

• Low Power: Ideal for energy-conscious designs and battery-powered BLE hubs.

• Interfaces: I²C, UART, or PWM for flexible microcontroller communication.

• ABC Logic™: Patented self-calibration that eliminates the need for frequent recalibration in most environments.

• Accuracy: Maintains stability and reliability throughout its lifetime.

Complete Smart Home BLE Automation Solution

System Overview

Each room in the home is equipped with:

• BLE Device Controller (ESP32 or similar microcontroller)

• Telaire T6713 CO₂ Sensor for air quality monitoring

• 5-Device Relay Control Module (LED lights, light load devices, heavy load devices, appliance control)

• Fan with PWM Speed Control

• Two Motion Sensors:

  • Door Sensor: Detects entry/exit.

  • Human Presence Sensor: Detects ongoing occupancy to avoid false triggers.

• AI Automation Engine: Processes sensor data and sends control commands automatically.

How It Works

1. Room-by-Room BLE Control

   • Every room is an independent BLE node.

   • The user can connect to the room’s BLE controller via a smartphone or central hub.

   • BLE ensures low latency and secure, localized control without relying on internet connectivity.

2. CO₂ Monitoring and AI-Driven Control

   • The T6713 CO₂ Module continuously measures CO₂ concentration.

   • If CO₂ levels exceed 1000 ppm (indicating poor air quality), the AI system:

     • Increases fan speed via PWM output.

     • Activates ventilation or opens automated vents.

     • Notifies the user through the mobile app.

   • When CO₂ returns to optimal levels (< 800 ppm), the system reduces fan speed to save energy.

3. Lighting Control

   • LED Light ON/OFF Control via relay or MOSFET drivers.

   • Light Load Control (e.g., table lamps, small electronics) for smart automation.

   • Heavy Load Control (e.g., air conditioner, heater) with relay isolation for safety.

   • Each device can be toggled individually through the app or automation rules.

4. Fan Speed Control

   • Fan motor is connected to a PWM controller driven by the BLE microcontroller.

   • Speed adjustments are automatic based on:

     • CO₂ levels (from T6713)

     • Temperature (optional DHT22/DS18B20 sensor integration)

     • User preference set via the mobile app.

5. Motion-Triggered Automation

   • Door Sensor: When someone enters, the room lights up automatically.

   • Human Presence Sensor: Keeps lights and ventilation on while occupants are inside. Turns them off after a set delay when no motion is detected.

   • AI can differentiate between short-term and long-term absence for better energy savings.

6. AI Integration

   • AI engine processes multiple inputs:

     • CO₂ concentration

     • Motion detection events

     • Light load usage patterns

     • Time of day

   • Executes automation scenarios like:

     • Night Mode: Dim lights and slow fans at night.

     • Energy-Saving Mode: Turn off non-essential loads when room is empty.

     • Fresh Air Mode: Boost ventilation during high CO₂ periods.

Example Operation Scenario

• Morning:
  Motion sensor detects entry → Lights ON, fan at low speed.
  CO₂ is low, so ventilation remains idle.

• Midday:
  CO₂ levels rise to 1200 ppm due to cooking → AI increases fan speed and turns on ventilation.
  Lights adjust based on ambient brightness.

• Evening:
  AI detects low motion activity + high CO₂ from multiple occupants → Keeps lights ON, increases fan to medium speed.

• Night:
  No motion detected for 20 minutes → Turns off lights and fan, except essential devices.

Hardware Integration Diagram

Room Setup:

Benefits of This System

• Healthy Living: Automatically improves air quality by responding to CO₂ levels.

• Energy Efficiency: Reduces unnecessary fan, light, and device operation.

• Scalability: Each room is a self-contained BLE node that can be expanded easily.

• Low Maintenance: T6713’s ABC Logic reduces the need for sensor recalibration.

• Real-Time Local Control: BLE ensures immediate response without cloud delays.

Applications

• Smart homes

• Offices and meeting rooms

• Gyms and fitness centers

• Hotels and guest rooms

• Classrooms and libraries