Automation, sensing and robotics • Re: Can't measure resistors

Chan2 0.026000793481246377 Chan1 3.0560932645649586 Chan 3.2700997955259865
loadRes2 4716.509433962258

Chan2 0.026000793481246377 Chan1 3.0560932645649586 Chan 3.2700997955259865
loadRes2 4672.429906542055

How can two exact same sets of input give different calculated results ?

I did however manage to calculate a matchig 4672.429906542056 result from the second item but I am struggling to figure out exactly what values you are measuring and have presented, especially the Pico readings. Maybe I am just too tired to figure it out.

But what's the other resistor value ? Without that it's not possible to calculate what the centre-tap voltage should be, see what sort of input errors there may be.

That 4672.429906542056 is just a 0.37% error if the R is 4690. Given the Pico has just a 12-bit ADC with an ENOB of just over 8 bits that seems pretty good to me.

Statistics: Posted by hippy — Mon May 06, 2024 11:57 pm

---