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I have a raspberry pi and a hall effect sensor which outputs 4v plus incremental voltages on top depending on the amount of current. Is it possible to take this voltage reading, convert it into a current reading (I have that formula) and display onto raspberry pi monitor?

maxwilliams25 wrote:I have a raspberry pi and a hall effect sensor which outputs 4v plus incremental voltages on top depending on the amount of current. Is it possible to take this voltage reading, convert it into a current reading (I have that formula) and display onto raspberry pi monitor?

maxwilliams25:
I'm not sure how your sensor works, but certainly you will need:

a) An Analog to Digital converter (ADC)
b) Probably some sort of amplification/filtering for the input signal.

Another ways is using a (very) low resistor value in series with the load and measure the voltage drop using a differential Op-Amp, again you need a ADC to convert this magnitudes to discrete signals that can be understand by the Raspberry Pi.

Good luck!

maxwilliams25 wrote:I have a raspberry pi and a hall effect sensor which outputs 4v plus incremental voltages on top depending on the amount of current. Is it possible to take this voltage reading, convert it into a current reading (I have that formula) and display onto raspberry pi monitor?

Hi there Max

I see what you mean. Good idea. So first things first you'll need a way to read a voltage that changes (Analogue voltage)

Here is a good topic on Analogue voltages : http://www.raspberrypi-spy.co.uk/2013/1 ... n-mcp3008/

then once you have that working it will be a simple case of using V=I*R, which for you will be V/R = I, i'm guessing your resistance is static? i.e. your reading in a signal of 4V's and the total resistance of the sensor is say 100ohms then current would be 0.040 or 40mA. The dev board i use mostly is the Mbed LPC1760 which has 6 Analogue inputs and makes this really easy! But the Voltage to current idea is a good one.

Hope this helps.