Arduino Internet Voltmeter with Dial Gauge, Logging and Graph
In this tutorial an Arduino Internet Voltmeter is made by using an Arduino and Ethernet shield set up as a web server to host a web page that displays voltage measured on one of the analog pins in a dial gauge on the web page.
An IoT (Internet of Things) web service called ThingSpeak is used to log the voltage and plot it to a graph. The graph of the voltage plotted over time is then displayed on the web page next to the dial gauge.
Voltage on the dial gauge is updated every 200ms for a near real-time view of the voltage. The same voltage is plotted to the ThingSpeak graph every 20 seconds.
For more details, please refer to the following link.
Author : startingelectronics.org, Not yet