Description:-

IoT or internet of things is an upcoming technology that allows us to control hardware devices through the internet. Here we propose to use IOT in order to control home appliances, thus automating modern homes through the internet. This system uses 4-loads to demonstrate as house Appliances Controlling. Our user-friendly interface allows a user to easily control these home appliances through the internet Worldwide. For this system we use an NodeMCU (Node Microcontroller Unit). This microcontroller is interfaced with a Relay modem to get user commands over the internet. Relays are used to switch loads. The entire system is powered by a 5V Adaptor/Charger (Micro-type). After receiving user commands over the internet, NodeMCU processes these instructions to operate these loads accordingly and display the system status on an Smart Phone Display. Thus, this system allows for efficient home automation over the internet. In this we have used the Blynk Community Application for controlling the Home Appliance all over the world. The Method used for controlling are Swiping the figures on Smartphone or Voice Control with Google assistant. Project having following features:- 1. Temperature and humidity monitoring system: DHT11 sensor is used to measure room temperature and humidity. Gauges will show the quantity of temperature and humidity at that time third gauge will shows the quantity of CO2 in the air at room temperature. 2. Gas leakage control system: When the smoke/Gas is sensed by the MQ2 sensor, the gauge value on blynk goes on increasing and when it reaches the value 600,then the buzzer turns on and gives alarm indicating excessive amount of of leakaged smoke/gas in air. And buzzer stops when the value decreases below 600. 3. Controlling home appliances using blynk and manual switches: Active low level triggered relay control mechanism is used here. When we tap on the particular switch on blynk ,then relay become ON and for next tap it will turn off. As well as we can control it it with manual switches also and the feedback is sent to blynk app i.e.the what is the current state of switch. 4. Controlling home appliances and through Google Assistant: We can control the appliances trough google assistance. For eg. "OK Google Turn ON the light" , "OK Google Turn OFF the light" and accordingly action will taken place. ie relay will turns ON and OFF respectively (Here IFTTT website is used to send the command through API to nodemcu).

Project Used Hardware

nodemcu(esp8266 12E),fuse with connector,PC817 optocoupler,1N4007 diode,5V relay,MQ2 gas sensor,DHT11 sensor,2.54mm screw terminals,single sided PCB,BC547 NPN transistor,9v battery with connector,female connector rails

Project Used Software

Arduino,easyEDA tool,Blynk 2.0,IFTTT(for google assistant integration)

Project Hardware Software Selection

As these hardware components provides more robust and reliable solution so by surveying this hardware components are selected.

Circuit Diagram

The schematic shown in picture is circuit diagram of project in which nodemcu esp8266 12E is used as main microcontroller which can be connected to internet and receive command from user through internet and also can send data to user over internet.in terms of sensor i have used MQ2 and DHT11 sensor to monitor air quality and room temperature,humidity respectively. PC817 is used so that we can provide 2 level isolation between microcontroller and load.2 5 volt relays are used to controll load,1 fuse is used to protect AC appliences connected to system from overcurrent and short circuit.