I have a sensor with a 10V analog output that i would like to read using my Arduino. I have found out i can use a voltage divider to bring the voltage down to 5V (although it doesnt seem totally clear what value resistors to use; is this just dependent on how much i want to limit the current? Or can i pick pretty much anything in a moderate range?) My big problem is that the sensor has a pair of outputs, a "Voltage" and a "Return". Would I be able to connect this to the Arduino by grounding the Return, then measuring the Voltage? (I guess im not totally sure what the relationship between the 2 outputs are, if both values are significant, or if just the differential voltage is controlled) Or do both outputs require measuring separately, then finding the difference in the values. I'd rather not do this, since the Return is marked as a negative value, and i dont want to have to convert it to be read by the Arduino. Any suggestions you may be able to provide would be greatly appreciated. Thanks!
You can probably connect the Return wire to Arduino ground and feed the Voltage output through a potential divider to an Arduino analog input, but I can't be certain with such limited information. Can you provide a link to the sensor datasheet? What is powering the sensor?
Sure, the website for the sensor is below. It is actually an intermediate step between the Arduino and a load cell. Page 19 of the user manual shows the circuit diagram of the output. After looking through the manual more, it actually looks like i might be able to scale the output down to 0-5V without a potential divider, which will make life a little easier.
The manual says that the unit is double insulated, so it looks to me that you can connect the Return line to Arduino ground.
If you do set up the unit to scale the output down to 0-5V, then use at least a 10K series resistor between the Voltage output and the Arduino analog input, to protect the input in the event of the unit putting more than 5V on its output. If instead you want to use a potential divider, them I suggest you use two 22K resistors.
Great, thanks for the help. I will hopefully get the time to try it out within the next week, and ill let you know how it goes!