I don't know how a Potentiometer works. :(

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Online I see lot’s of different ways of wiring a Potentiometer.

I’ve seen this configuration. This makes sense to me :slight_smile:

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But I’ve also seen this configuration where the power is connected to PIN1 and the Variable PIN(2) with Data coming out of Pin3

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This second config actually works which is really surprising to me.
If the resistive strip is just tied to power, why would it continue to impact the outer terminals? In this second config am I even completing the circuit?
What is going on here?

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Hi Pix
This surprises me.
I thought you had a better grasp of this electronics subject than that.
The top one is a potentiometer, the bottom one is connected as a rheostat and if you connected this across a power supply as indicated it probably would end up as a disaster. maybe for the component or the power supply.
Suggest you do some research on the subject. A bit too involved to attempt a 5 minute course in basics here
Cheers Bob
EDIT: Sorry you have got this marked V and D I thought it was V and G. Still would not be good, depends on what hangs off the D.

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Man, tell me about it! Every time I start to feel like I found my feet I see something that just throws me off.

In this case, I just had no idea what to search!
I tried things like Different schematic of a potentiometer and 2 ways to wire a pot

But now thanks to you I have my search term : rheostat’
Now I know what to look for to learn more :slight_smile:
Thanks again Bob.

Pix :heavy_heart_exclamation:

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Hi Pix
The short explanation
A potentiometer is a variable voltage divider.
A rheostat is a variable resistor.
When a potentiometer is connected so the slider is connected to one end it becomes just 1 variable resistor and is said to be rheostat connected.
Cheers Bob

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My confusion here is hilarious.
If like me someone has mostly used the Potentiometer with a micro-controller, they might start to always think of pots as voltage dividers since that’s the config you need for analogue pins.

Above, I’m confused because I’m expecting the second configuration pictured in my original post vary to the voltage coming out of the right most pins. That’s wrong; it wouldn’t (much) impact the voltage of the data terminal but it would vary the resistance.

I think I have made pots in the rheostat config before when I’ve been following circuits from “The Art of Electronics” by Horowitz and Hill. AOE mostly uses schematics, so I have never, until I saw that youtube video today, seen someone just solder slider to one terminal before.

Now I know :slight_smile:
Thanks again Bob.

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Hi Pix

Because the outer terminals are connected to the slider via the resistive strip. The voltage here will not vary until you connect a load of some sort. Basic Ohm’s Law or if you want to get really technical Mr Kirschoff had something to say about this.
Cheers Bob

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