Analog output varies despite having something conected to it

Im doing a proyect that needs to read the value coming from a potenciometer and despite the fact that i have conected everything right (The potenciometer's right pin is conected to 5V, medium pin to A4 and left pin to GND) I've notice the analog values fluctuate a lot despite me not moving the potenciometer, what could be causing this?


The noise can be mitigated, somewhat, with a 0.1uF ceramic cap from the wiper (pin A4) to ground. It will shunt higher frequency noise to ground. Value not critical.

How much is "a lot"? What values? It might be noise in long wires or poor connections. Breadboards are often the culprit here because potentiometer leads may not fit well.


What size wires are you using?
Are they solid or stranded?
How long are the wires?
Are they twisted or do the cross each other?
Is this in a breadboard, soldered, or did you use push-on connectors?
I think some detailed pictures and answers will help you get better help.

Show us a good schematic of your proposed circuit.
Show us a good image of your ‘actual’ wiring.
Give links to components.

In the Arduino IDE, use Ctrl T or CMD T to format your code then copy the complete sketch.

Use the </> icon from the ‘reply menu’ to attach the copied sketch.

Values can change 300+ units at any time, the wires aren't longer than 10 cm and they are directly conected to the arduino uno. The only thing that i think could be wrong is the fact that both the 5V and GND wires are spliced since i need to conect multiple potentiometers to the same 5V and GND pins

If you want help, you need to provide what’s requested.

Yes, that is "a lot" and something is wrong. Maybe the pot is wired wrong... Sometimes the slider is not physically the center contact.

What's the value of the pot? (Higher values tend to pick-up more noise.)

What happens at the minimum & maximum rotation?

You're describing an analog input. :wink:

Upon further investigation seems like I did an asbolute horrible job splicing both the 5V and GND wires since when I did the test on a single potentiometer using un-spliced wires it worked perfectly, so I´ll be doing the splicing all over again

Ppl sometimes use solder to good effect.



That’s why we need to see your actual wiring, schematic, and software sketch.

Always blame yourself first.