Humidity & Temperature Monitoring using DHT11 & NodeMCU on ThingSpeak:
This tutorial is all about Humidity & Temperature Monitoring using DHT11 & NodeMCU on ThingSpeak. It explains how to log Humidity & Temperature data on cloud. We can use Thingspeak as cloud service provider and DHT11 to measure temperature and humidity.
This tutorial is for NodeMCU on Arduino IDE. You can also configure ESP8266 board with Arduino to monitor temperature and humidity.
You just need NodeMCU ESP-12E WiFi Development board and a humidity sensor DHT11 or DHT22. In addition to these breadboard and connecting wires are required.
DHT11 Humidity & Temperature Sensor:
The DHT11 is a basic, ultra low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed).
Its fairly simple to use, but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds, so when using the library, sensor readings can be up to 2 seconds old.
Circuit Diagram & Connection:
Setting Thingspeak & Getting API Key:
1. Go to https://thingspeak.com/ and create an account if you do not have one. Login to your account.
2. Create a new channel by clicking on the button.Enter basic details of the channel.Than Scroll down and save the channel. You can follow the video guide below.
3. Then go to API keys copy and paste this key to a separate notepad file. You will need it later while programming.
The program for Humidity & Temperature Monitoring using DHT11 & NodeMCU on ThingSpeak is given below.
1. Copy this program and paste it on Arduino IDE.
2. Download DHT11/DHT22 library from github and add it to your library manager.
3. Select NodeMCU ESP-12E board from board manager.
4. Paste you API Key from thingspeak which you created earlier on programming section line.
5. Edit the program to change the wifi ssid and password with your own.
6. Compile the code and Upload it to NodeMCU board