Potentiometer is not dimming my LED when adjusted.

I am using an Arduino UNO. My configuration from 5V power input pin to ground pin is as follows:

5V power port Arduino->negative rail of BB->-10k potentiometer*->green LED->330 Ohm resistor-> positive rail of BB->ground port arduino.

*potentiometer (middle pin)-> Analog input A0 arduino

When i run the 'ReadAnalogVoltage' beginner example program and switch on the serial monitor i receive voltage readings and the led is lit. When i turn the dial on the potentiometer, the voltage reading changes from min 0.00V to 2.6V(ish) but no dimming or brightening is observed by the LED.

(not) My potentiometer has three pins in a triangular orientation (like a British plug) which i have plugged directly into the bread board.

why am i not receiving a voltage reading between 0-5V readings and why don't i observe a dimming effect?

Thankyou

ardoing:
I am using an Arduino UNO. My configuration from 5V power input pin to ground pin is as follows:

5V power port Arduino->negative rail of BB->-10k potentiometer*->green LED->330 Ohm resistor-> positive rail of BB->ground port arduino.

*potentiometer (middle pin)-> Analog input A0 arduino

When i run the ‘ReadAnalogVoltage’ beginner example program and switch on the serial monitor i receive voltage readings and the led is lit. When i turn the dial on the potentiometer, the voltage reading changes from min 0.00V to 2.6V(ish) but no dimming or brightening is observed by the LED.

(not) My potentiometer has three pins in a triangular orientation (like a British plug) which i have plugged directly into the bread board.

why am i not receiving a voltage reading between 0-5V readings and why don’t i observe a dimming effect?

Thankyou

Your description makes no sense. Please make a schematic drawing of how you have things connected. Scan it or take a picture of the drawing and post it.

Paul

Paul KD7HB, An illustration of my breadboard configuration is shown available in the link below.

Thanks.

All the parts in row 24 of the breadboard are shorted together.

Search Google images for "Breadboard connections". Leo..

If the led is lighting up, it cannot be wired the way it is drawn.

And lol, use the + bar for negative and the - bar for positive, really? :D

And indeed, if it lights up you didn't connect it this way.

But if you did connect the led in series with the pot and resistor then yeah, the pot will not change the led. Only the wiper pin of the pot changes and that's only going to analog pin... So as far as the led is concerned the pot is just a 10k resistor.

Thanks for your feedback. I was under the impression that the 'positive electron' was just an electronic engineering convention. I just find it easier to understand negatively charged subatomic particles moving to the positive terminal. Never the less, i have tried switching the terminals with more or less the same series configuration and the LED still lights up. I'll try the parallel config.

Thanks again.

First, try to post what you really do ;) Like said before, if it's connected like in your drawing the led is just off.

Series configuration, different pins, same series configuration.

http://imgur.com/kOBlAhU

Don’t make us click out to your links.
Attach the image like I am doing.
Save the post.
Go back and modify the post.
Right click on the attachment to copy image location.
Use the insert an image button.
Paste in the location.
Save.

Then everyone can see the image without having to follow links.

kOBlAhU.jpg

Thanks, Appologies for the inconvenience.

ardoing: Series configuration, different pins, same series configuration.

septillion: But if you did connect the led in series with the pot and resistor then yeah, the pot will not change the led. Only the wiper pin of the pot changes and that's only going to analog pin... So as far as the led is concerned the pot is just a 10k resistor.

Your answer ;)

The ReadAnalogVoltage sketch from the examples uses pin A0, you use A1. Did you adjust the sketch for that.

It also states to connect the outside pot pins to +5volt and ground. Your pot is connected to +5volt and LED.

The LED/resistor needs it's own circuit (between a PWM pin and ground). Pin13 is not a PWM pin. PWM pins have a ~ in front of the pin number on the board. Leo..

A 10k pot has a constant resistance between the two end terminals (10k ohms), regardless of the position of the pot. The resistance between the wiper and the two ends changes, though the total resistance is of course always 10k.

So as far as the LED is concerned, your circuit looks like this regardless of the position of the pot.

+5v ----/\/10330 ohm\/\/---(LED)--- Gnd

The 10330 ohm resistance is very high for current limiting (you're getting like 0.3mA, instead of around 10mA), hence why the LED is dim.

In other words, as others have explained above, you've got it wired in a very different way from what I think you want.

ardoing: I was under the impression that the 'positive electron' was just an electronic engineering convention.

No it is real, it depends on the material which is involved more. Look up the concept of majority carries.

But if you think the actual direction of electricity flow matters, then you are misunderstanding something.