On a test board, I made a simple circuit that I hope to measure the current used from a 12V 7.2 Amps battery.
I never done this before, so if I am completely off... please be pacient and explain the right way to do this...
I did not connect it to the PIC microcontroller because I was afraid I will damage it in some way, this is why I want to get aproval from you first.
I attached the test circuit, the input is a 12V 7.2 Amps battery, and the Load I put a 12V 50 Watt light bulb. The battery was almost discharged when I tested it ( I'm charing it now )
I used an Ammeter and it shoed 3 Amps on the Load, then I tested the voltage on the "To PIC" and it showed ~210 mV
So because of the mesurements, I think it is safe enough to plug the PIC in, and measure through it's analog input.
I have a question:
How to get an accurate input from the PIC ? I mean, when it was 3 Amps, it showed 210 mV, so it's not like there is a 1 to 1 correlation between Amps and Volts...
I never done this before, so if I am completely off... please be pacient and explain the right way to do this...
I did not connect it to the PIC microcontroller because I was afraid I will damage it in some way, this is why I want to get aproval from you first.
I attached the test circuit, the input is a 12V 7.2 Amps battery, and the Load I put a 12V 50 Watt light bulb. The battery was almost discharged when I tested it ( I'm charing it now )
I used an Ammeter and it shoed 3 Amps on the Load, then I tested the voltage on the "To PIC" and it showed ~210 mV
So because of the mesurements, I think it is safe enough to plug the PIC in, and measure through it's analog input.
I have a question:
How to get an accurate input from the PIC ? I mean, when it was 3 Amps, it showed 210 mV, so it's not like there is a 1 to 1 correlation between Amps and Volts...
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