IoT Temperature Monitoring & Control System using ESP32 & Blynk 2.0 | SMS Alert

Summary

In this tutorial, we demonstrate how to build a temperature monitoring system using an ESP32 microcontroller, a DHT22 sensor, and the Blynk app. The system allows users to remotely monitor temperature in a designated area and set a threshold. Once the temperature exceeds the set value, the system sends a text message and triggers an alert on the Blynk app. The guide covers the necessary components, circuit setup, and step-by-step instructions for coding, setting up the Blynk app, and testing the system to ensure everything functions as expected. Perfect for electronics enthusiasts looking to enhance their IoT skills!

Takeaways

• 🛠️ The video demonstrates building a temperature monitoring system using an ESP32 microcontroller and a DH8 V20 temperature sensor.
• 📱 The system integrates with the Blynk app to remotely monitor temperature and set threshold values.
• 🔔 When the temperature exceeds the set threshold, the system triggers a buzzer, LED, and sends an SMS alert to a specified mobile number.
• 💡 Components used include ESP32 board, 16x2 LCD display, SIM800L GSM module, digital temperature sensor, lithium-ion battery, and optional relay module.
• 📊 The Blynk app dashboard uses sliders for threshold values, LEDs for alerts, and a gauge to display real-time temperature readings.
• ⚡ Hardware assembly involves connecting components with I2C and digital pins, adding a battery charging system, and positioning the GSM antenna for better signal.
• 💻 The Arduino IDE is used for programming, requiring installation of specific libraries for LCD, temperature sensor, and I2C communication.
• 🔌 The code defines pin connections, serial communication, temperature reading, LCD display, threshold comparison, and SMS commands.
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• 🌡️ Users can adjust the threshold value dynamically through the Blynk app, which directly influences the system’s alert behavior.
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• ✅ The video demonstrates the system’s functionality by heating the sensor, showing LED and buzzer activation, SMS notification, and LCD display updates.
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• 📢 The creator encourages viewers to like, share, and subscribe to the channel for more electronics project tutorials.

Q & A

What is the main purpose of the project demonstrated in the video?

The project is a temperature monitoring system using an ESP32 microcontroller that sends SMS alerts when the temperature exceeds a set threshold. The system also allows remote monitoring and threshold adjustment via the Blynk app.

Which components are used in this temperature monitoring system?

The main components are ESP32 microcontroller, 16x2 LCD display, SIM800L GSM module with SIM card and external antenna, a digital temperature sensor (like DS18B20), a lithium-ion battery (3.7V), and optionally a relay module and buzzer.

How is the temperature sensor connected to the ESP32?

The digital temperature sensor is connected to pin 14 on the ESP32.

What is the role of the Blynk app in this project?

The Blynk app allows users to monitor real-time temperature, set a temperature threshold via a slider, view an LED indicator when the threshold is crossed, and see a gauge displaying the current temperature.

How does the system alert the user when the temperature crosses the threshold?

When the temperature exceeds the threshold, the system triggers a buzzer, turns on a fan (through a relay), lights up an LED in the Blynk app, displays a warning on the LCD, and sends an SMS notification to a specified mobile number.

Which pins are used to connect the SIM800L GSM module?

The SIM800L module is connected to pins 16 and 17 of the ESP32 for serial communication.

What libraries need to be installed in the Arduino IDE to run this project?

The required libraries are the Blynk library, a library for the digital temperature sensor, and an I2C LCD library if the LCD display is used.

How is the temperature threshold value configured and adjusted?

The threshold is set via a slider in the Blynk app using virtual pin V1. This value can be adjusted remotely, and the ESP32 reads it to compare with the real-time temperature.

What are the steps to prepare the ESP32 board for programming in Arduino IDE?

First, install the ESP32 board by adding the Additional Board Manager URL in Arduino IDE settings. Then, install the required libraries, select the correct ESP32 board in Tools, and choose the proper COM port before uploading the code.

How does the system behave when the temperature is below the threshold?

If the temperature is below the threshold, the system remains in normal mode: the fan and buzzer stay off, the LED in the Blynk app is off, and no SMS is sent.

What additional precautions are recommended for reliable operation of the system?

Use an external antenna for better GSM signal, ensure all libraries are installed correctly, verify that virtual pins in code match the Blynk app, and use a stable power supply for the ESP32 and GSM module.

What outputs indicate the system is functioning correctly during testing?

Correct functioning is indicated by real-time temperature display on the LCD and Blynk gauge, LED lighting up when threshold is crossed, fan and buzzer activation, and receiving SMS alerts for high temperature.