I'm trying to build a device where I can measure how much voltage level of a batter (like a car battery). I'd like to be able to run power and ground from the battery to the board (to an input pin?) and get measure the voltage.
Any advice? Are there any readily available IC's built for this purpose?
Thanks!
You can use a voltage divider and the Arduino ADC input, as described for example here: Measuring Voltage with Arduino
Place a 1/2 amp fuse at the battery incase you accidentally short the wiring.
I'm not sure I understand what this product does. Will it do what I'm looking for?
No.
That is a current measuring board.
It measures the current a load draws.
You asked for measuring voltage.
Voltage can be measured directly with an analogue pin of the Arduino.
But since you want to measure more than 5volts, you need a voltage divider.
Two resistors with a ratio of ~1:2
So you reduce the ~12volt of the car battery to 1/3 of that, ~4volt.
Leo..
Wawa:
You asked for measuring voltage.Voltage can be measured directly with an analogue pin of the Arduino.
But since you want to measure more than 5volts, you need a voltage divider.
Two resistors with a ratio of ~1:2
So you reduce the ~12volt of the car battery to 1/3 of that, ~4volt.
Leo..
If you are measuring an automobile battery while in a vehicle and the engine is running and charging the battery, you may get voltages above 15 volts at times.
Paul
Add a 5.1V zener to help safeguard against higher voltages, or a surge protector device:
The link in post#1 uses a 1Megohm/100k resistor divider.
I doubt if anything can go wrong there.
You have to put 1000volt on that resistor for 1mA protection diode current.
But indeed, if you use low value resistors, a zener might be needed.
Leo..
Hi.
Wouldn't it be easier and cheaper to by an alcheepo DMM?
This is the only criteria;
I'm trying to build a device where I can measure how much voltage level of a batter (like a car battery).
Tom... 