5 wire potentiometer questions

I have a 5 wire potentiometer that I’m trying to figure out. Seems like it’s more difficult than it should be lol.

It looks pretty much identical to this one:

Except the colors of the wires are in different spots. Not sure yet if that is because this pot is different, or if the wire colors are just colored wrong.

On the bottom connections the red and black wires are reversed from the pictures, and I have verified where this pot plugs in there is 12v feeding into that wire pair as positive / negative.

But, I can’t figure out the top wires. They are colored from left to right red, black, yellow. When I switch it on as well as turning it all the way up, I’m not getting any voltage readings with any combination of the 3 top wires.

Resources from : https://www.kynix.com/Blog/How-to-Wire-a-Potentiometer.html

The plan is to use it as a motor speed controller. What I’d like to do is make the pot control wireless rather than having to extend the pot wires and have them get in the way. So, I was trying to figure out how the pot signals were incorporated into this board so that I could replicate them using an arduino. The wireless communications and all I can handle easy enough, I’ve done that numerous times. Just seem to be having trouble figuring out how this pot works with the rest of the circuit lol.

Any guidance would be much appreciated.

Without exception all pots are wired like this:


Pin 1 to pin 3 is the full value of the pot.
Pin 2 is the wiper

The two wires are likely a switch as you said. You should verity this before hooking it to anything.

Wire colors: random. There is no standard for pot wire colors.

Typically you would connect:

1 to Vcc
3 to common (aka ground)
2 to an analog input.

If you reverse pins 1 and 3 the pot will work exactly the same but in the opposite direction. i.e. if it was a volume control and reversed, you would have to turn it CCW to lower the volume.
Connecting it normal or reversed are both perfectly fine, it just depends on how you want the circuit to work.

So that would leave two wires for the switch function that could be completely electrically isolated from the pot function?

So this potentiometer was part of some unit, or it was a component which was not originally associated?

Are you trying to control the on/off function with the switch portion?

If you measure ohms with a multimeter, the two wires connected to the potentiometer ends should measure ~100K ohms to each other regardless of the knob position. Then the wiper will measure some value X to one end and (100K ohms - X) to the other end. The value X will vary with the knob position. There is no risk in measuring potentiometer ohms with a multimeter because current and voltage from the multimeter will be too low to damage anything such as this.

If you want to use potentiometer to control the motor speed, just use simple 3 pin potentiometer and i assume you are using dc motor so you can control the polarity with arduino itself.
why do you need “switch wire” because simple potentiometer will work to on-off. and still if you want witch control you can add external switch to arduino input to control the motor if you need.
about that 5 pin Potentiometer I find this image in which its used to control two signal.

Provided it is linear potentiometer and not Log or Inverse log.

Original post specified the potentiometer is linear. They should have no issues reversing this potentiometer.

Usually, yes. But you should check with an ohmmeter

Well, that is how a lot of early portable transistor radios worked as I’m sure I don’t need to tell you. :wink: The switch was closed to power the radio when the volume dial was moved from lowest volume. Though I would expect the pots on those to have been audio taper.

@Rachel_Anne Check on your switched pot what end of travel the switch is activated (most likely opened, but double check on your unit), and use that position as your zero rotation (or low speed) position on the pot using @JohnRob’s picture in the second comment to figure out how the pot should be wired to the requirements of your circuit. Too many variations on how this is applied to give any advice, other than ignore the wire colors and look at where on the part the wires are connected. (And perform a sanity check with an ohm-meter to make sure your device matches expectations.)

Yes, there are standards, but there are so many (often conflicting) standards that you should always verify. XKCD has a cartoon about this

Yes in fact when I was a kid a neighbor kid told me that his radio needed no batteries because it was “all transistor”. Our first transistor radio was tiny; maybe maybe 6 cm square. I think it took a single AA battery. (For that to work it might have used germanium transistors.) The sound quality made a croaking frog sound like the New York Philharmonic by comparison. But you could listen to the news.

One other thing to watch out for…in volume controls, spend the little extra for a “Cermet” potentiometer instead of a carbon type. I have a bunch of old radios in the house where the only problem is a noisy volume control. And it becomes a serious problem (at least up to the price of a new radio.) A spritz of “tuner cleaner” works only for a little while on an old one.

Or maybe one 9V battery. One of these days I’ll give up silicon for geraniums. :wink:

I had a crystal set like this as a boy - look, no battery (but also, no volume) :wink:
Upgraded after a while to a long antenna strung up on my mothers washing line and a tuning capacitor.


After which you apply a few drops of light oil (sewing machine type) to turn it into a longer while.
If you prefer, use grease. It will never crackle again; mind you, it will never work again either. :grinning:

This one definitely did not take a 9V battery. The question is between AA and AAA; one or two. But I am 90% sure that it was one AA battery. This would have been 50+ years ago.

So did the light machine oil allow the radio to work or just be silent?

NOTE: I had devised a debounce add-in circuit for my trackball to deal with contact bounce. This worked nicely until the contacts apparently deteriorated much further. But I was discussing this with a colleague who used to have an electronics repair shop in Iraq. He told me to spray some contact cleaner as well as I could into the trackball switch. I said something to the effect of “that will never work.” I saw no way that contact cleaner would deal with the fatigue of switch contact spring metal. But…surprise…it worked!

2 AA was the norm for pocket “transistors”
or trannies here which was perfectly realisable. Usual configuration was 3 RF transistors and 3 AF transistors, the last 2 in push pull driving an audio transformer. Ge transistors were used because they were prevalent type; I didn’t get my hands on Si transistors until the mid-70s, being a humble school kid.

Well this discussion raised my curiosity . My fault!

This is a link to a radio that looks very similar to what I remember:


According to this, we are both WORNG about the battery. It claims a 4.5V battery. That surprising result seems difficult for me to accept but the other links I can find generally agree. So my memory has been victimized via (salt and) a battery. (??)

Probably an age related problem, I know the feeling. :slightly_frowning_face:

That model you remember maybe but nearly all the ones I encountered in the Far East which were made in Japan or HK used 2 AAs because a special battery would have been a unselling point. AA cells were ubiquitous, 9V was available (stack of 6 cells), 4.5V I don’t think I ever saw one.

In Poland each of us has the identifying number used in all official documents (diving licence, identity card) and all offices. This number begins from your birth day. Its name is PESEL (abbreviation of some words).
This problem I name: PESELoza (PESELosis - I’m not sure which ending to use to sound like the name of the disease).

4.5V was the basic battery I used in childhood (AA batteries those time had very little capacity and it was easy to connect to 4.5V battery - you could solder wires to its ends).
I was able to power the LM741 with one 4.5V battery. After experiments I set voltages for something like + 2.7 / -1.8 to get the 1V (from 0 to +1) linear output range. It was my electronic voltmeter (the voltmeter I had had too small internal resistance as for transistor circuits to measure).
When I was making a cybernetic turtle and I only had a 24V relay, I used 5 4.5V batteries to power it. The batteries and the relay (a huge one - it came from some war bomber) were so heavy that the turtle was unable to break out of the rotation (looking for the light) when it saw the light. The motor driving the second wheel turned on for a moment, but after a while the light disappeared and so on.