Your knowledge is needed!
I have a need to sense DC voltage from three separate electrical lines and send the signals to light a series of LED's. In between will require what I assume to be an Arduino w/ Zigbee (Or some other relevant transmitter) and a Arduino transceiver to collect and show the appropriate "Line condition" on the 3 light panels.
Where you could help?
What Arduino(s) are right for the project?
What voltage sensors? (+5v to +25v)
Project Mentor?
Possible Project Programming
~D~
Since you don't need a lot of I/O, a Uno would be more than sufficient. If space is really constrained there are smaller versions like the Nano, but if you aren't very experienced with Arduinos I'd recommend sticking with the Uno.
How much accuracy and precision do you need to measure the voltage on the +25 VDC lines? If you just need a rough idea, you could use a voltage divider on each line, e.g. droping the sensed voltage by a factor of between 5 and 10, and connect the resulting lower voltage into three separate analog input pins on an Arduino.
Foor higher voltages I'd recommend using the 1V1 Vref too as when using a divder the Granularity of the measurement will be degraded by the divider ratio. With a "Standard" Vref of 5V the minimum step size is 5/1024 or 4.88 mV so you can resolve 2 bits or worst case 9.7 mV/5V now divide a 25V signal by 5 to fit it into the 5V max range of the A/D and your minimum step is 5 X 4.88 mV or 24.4 mV/step or effectively 48 mV/2 steps or bits. Using the built in 1V1 Vref will bring the voltage measurements back in line. There is also one more "advantage" and that is that the 5V Vref is the processor Vcc and If you are powering the device from the USB port the Vcc might not be 5V... So the measurement is "Ratiometric" or relative to the actual Vcc and not a "Standard" Vref, where the internal 1V1 Vref is regulated by the Processor and will provide more accurate measurements. For ultimate accuracy the measurement should be calibrated by comparing the results at 3 points low, middle... with an accurate DMM so as to insure that the measurements are accurate and linear. This simple method has served me well for many years.
Bob