Read the voltage of the battery while powering it

Using Arduino Sensors
1

is their any way to measure the voltage of a battery while powering the arduino?

2

vhenamae:
is their any way to measure the voltage of a battery while powering the arduino?

Sure, the typical way is to wire the battery voltage to a two resistor voltage divider and the then attenuated voltage is wired to a arduino analog input pin.

Lefty

3

is it fine if the power im using for the arduino is the one im measuring?

4

is it fine if the power im using for the arduino is the one im measuring?

Duzn madder.

Rob

5

vhenamae:
is it fine if the power im using for the arduino is the one im measuring?

Not an issue in itself. The issue is that there must not be more then Vcc + .5vdc applied to a analog input pin. You haven't given us the battery voltage you will be using, but assuming it's more the +5vdc then some kind of voltage divider is a commonly used method to be able to measure it's value. One issue with that however is that the divider will consume some battery current at all times, unless there is a on/off switch between the battery and the voltage divider string.

6

i see.. actually ill be using NiMH 9v 200mA battery..

7

So it is going into the Vin or power jack and being regulated to 5V, that is the voltage reference for the measurement. Then a potential divider will cut this raw voltage down into the 0 to 5V region for you to measure.