Potentiometer shutting off Arduino

Hello,

First things first, let me state that I am a beginner with Arduino. I am trying to use an LCD and display characters to it, and I am using Adafruit's tutorial for it. The website is https://learn.adafruit.com/adafruit-arduino-lesson-11-lcd-displays-1?view=all . It uses a potentiometer, but when I turn it all the way counter-clockwise, it completely shuts off my Arduino. I don't know why this is happening, I would greatly appreciate some help.

Thank you!

Sounds like a short circuit on the supply. Check your wiring

Sounds like you have either 5v or gnd on the middle (wiper) pin of the pot so cranking it all the way presents a near short between them.

Hi, and welcome to the forum. Did you connect the center pin to the analogue input (or LCD), and the outside pins to supply and ground. If not, then turning the pot to an endstop will short out the supply. Post a picture if you're not sure. Leo..

Read WAWA s and DRAzzy s comments. I bet they are right!

Wawa: Hi, and welcome to the forum. Did you connect the center pin to the analogue input (or LCD), and the outside pins to supply and ground. If not, then turning the pot to an endstop will short out the supply. Post a picture if you're not sure. Leo..

The potentiometer that I am using is not the same potentiometer used in the Adafruit tutorial. Is this what could be causing problems? It looks like this one, with two pins on one side and one pin of the opposite side. http://i1262.photobucket.com/albums/ii618/simo1717/1bc12511-bf16-4733-a1a9-d560320006d3_zpsbf9c7edb.jpg

The single pin on the other side is the wiper, and has to go to the LCD. Maybe there is a short on the LCD side. Disconnect the wire to the LCD, and try turning the pot then. See if your Arduino still shuts off. Leo..

Wawa: The single pin on the other side is the wiper, and has to go to the LCD. Maybe there is a short on the LCD side. Disconnect the wire to the LCD, and try turning the pot then. See if your Arduino still shuts off. Leo..

Looking at the Adafruit breadboard layout, I unplugged the red wire that connected to the potentiometer and now the Arduino does not turn off upon turning. However, when I upload the AnalogInOutSerial example to my Arduino and open a Serial Monitor, the values are not changing when I turn the potentiometer. One of my friends told me that this is how you test to see if your potentiometer is functioning properly, so what is wrong now?

improper wiring? bad potentiometer? Hard to say. Was it the correct value for the LCD? Was it the Adafruit LCD you were using?

It would be extremely helpful if you could post exactly how you have it wired up.

show a photo of your wiring.

Have you got a multimeter? (Correct answer: "yes" ;) )

You should get a constant resistance across the the outer pins of the pot, 10k or whatever the pot's value is. That won't change as you turn it.

Then the value between the 3rd pin, the wiper, and either end will change as it's turned. Full one way will give 0 and full the other way is the max.

I'd say that's the way to test it...

Hi all,

Thank you everyone for your replies; my potentiometer is now correctly functioning and is no longer shutting off my Arduino.

AidanG: my potentiometer is now correctly functioning and is no longer shutting off my Arduino.

Cool: in the spirit mutual cooperation to help others who may have the same issue, you might explain what was actually happening and what you did to fix that.

manor_royal: Cool: in the spirit mutual cooperation to help others who may have the same issue, you might explain what was actually happening and what you did to fix that.

Seeing as I had a different potentiometer than the one on Adafruit, I got confused by the diagram and dumb me put the pot in backwards, thus the wiper was not actually going to the LCD. Simply turning my potentiometer around literally fixed everything.

I am quite the beginner at this, but hey, I'm learning.

Plugging something in backwards is practically an initiation rite for this hobby. I just spent 2-3 days figuring out how to make some new microcontrollers (PICs) blink an LED. Don't let it get to you.

AidanG: Seeing as I had a different potentiometer than the one on Adafruit, I got confused by the diagram and dumb me put the pot in backwards, thus the wiper was not actually going to the LCD. Simply turning my potentiometer around literally fixed everything.

I am quite the beginner at this, but hey, I'm learning.

Doesn't sound right. Potentiometers have 3 pins, with the wiper being the middle pin. Since the outer 2 pins are just the total resistance, and it makes no difference which direction voltage is applied, simply spinning the pot 180 degrees would not change the electrical characteristics of the potentiometer. The wiper would still be the center pin, and the outer pins would still be the total resistance.

You must have changed some wires, whether you know it or not. Since it was shorting it, I would guess ground or Vcc was on the wiper.