Thread: adc unit voltage out

I have gm 3 bar map sensor that I am trying to use for datalogging. The adc unit conversion wont go less than whole unit. I want at least 2/10 for accuracy reading. The raw voltage unit never display the raw voltage but the the conversion 0v= 500, 5v= 5000. With volmeter I found I got 1.62v at 0psi at the adc unit. I know map sensor will differ at different altitude. From my research I found that gm 3 bar map sensor output is
psi volt
-28.5 0.078
0.06 1.641
30.0 5.0

I tried putting min 0.078v = -28.5psi and 5.0v = 30 psi. I can never see the same output between pressure gauge and adc unit out. Anybody have idea how I can solve this problem.

Thanks

At this point I am not supporting the GM map sensor directly, BUT if you do have a genuine GM sensor you should be able to use the Omnipower 3 bar sensor as it uses the same conversion.

Then select psi as the unit, please note that the mbar unit will be the most accurate at this time. It has been brought to my attention that there is an error when converting to psi which I need to address in the next update!