Hello friends!!
I am here to show you a DC wattmeter which can be made easily by using Arduino nano. One of the main problems I was facing as an electronics hobbyist is to know the amount of current and voltage applied across the charging circuits I made. I thought of buying one meter from an online store, but one of my friends told me that it is having a huge error while measuring the current.
So I thought of making it using arduino.it can also be used to charge batteries with auto cut off by making some modifications.