“Hello friends In this post we will learn how to make a ESP32 IOT based Home Automation project using Blynk 2.0.
This days we here lots about IOT, IOT stands for Internet of things.
In this project we build a system using ESP32 and internet so that we can control heavy loads of out home like, LIGHTS, FANS, AC, etc.
I have used ESP32 board because obviously it have WIFI capability so we can connect it via internet and send command to turn load ON & OFF via Blynk IOT cloud.
Also I have used ULN2003 IC it is array of seven NPN Darlington transistors, the output voltage level of digital pins of ESP32 is limited to 3V so it is not advisable to turn 5V relay ON through this pins.
So here ULN2003 make our work easy, ESP give digital inputs to ULN2003 and ULN2003 turn on Relay respectively.
I have used LM7805 SMD linear voltage regulator to make sure to get regulated 5V supply of ESP32 ANS Relay coil.
I have also used FR207 diode to protect circuit from cross polarity, also used on 5mm Green led to indicate POWER is available at PCB.
3mm Red LED is used one for each relay this LED indicate the state of relay, if LED is on means Relay is on vice versa.”