I've been working on this for a while, even paid someone recently, and I'm still not happy with the results. I have a coffee roaster with a proportion valve for the gas, and a digital gas meter that outputs a 4-20mA signal. What I'm looking for is to have a hand held module (which I've already 3D printed) with the following features:
-LCD Display (installed) and currently reads Gas Pressure in kPa and Total Gas %.
-LCD Display a scale on bottom of screen that displays on a scale between 0-5 what the current gas setting is.
-Potentiometer or Rotary Encoder for controlling gas pressure (Proportion valve with driver)
-As for hardware, I have a small PCB that converts the 4-20mA signal from the gas gauge to higher voltage for Arduino to read - This needs 9volts.
-The valve driver needs 12-14volts.
So in the end I'm looking for someone who can refine (fix) the current sketch I'm using, as well as assist in creating (modifying the current shield I created in Eagle) the proper circuit to power everything and read all the data.