Potentiometer Overheating

Hello! I’ve been working with a 25K Linear Taper Potentiometer 1/4" Shaft and I am facing issues with the potentiometer rapidly overheating. It requires 2.5-5.5 volts, but for some reason with very limited use it ends up heating up very quickly. I’ve added a resistor, but nothing helps. Would a higher gauge wire help with this??? Any other solutions?

As discussed in your other thread, it appears that your potentiometer is wired incorrectly. 5V applied to a 25kΩ potentiometer will only draw 0.2mA, meaning that there will only be 0.1mW disspiated in the potentiometer. This is a REALLY small amount of power for anything you can see from more than a few feet away.

I suggest that you (power off) put the resistor in a mid-position, and measure the resistances from A-B, B-C, and A-C, defining A, B, and C as you see fit. The pin which is NOT participating in the largest resistance is the sweep. The 0V and 5V should connect to the other two pins; the sweep should connect to the analog signal input.

I have to agree with @GeeTwo. Either something is wrong with the potentiometer internally that is lowering the resistance considerably, or, more likely, you have the potentiometer wired incorrectly. Most potentiometers have the signal pin in the middle, with voltage and ground on either side, but this isn’t always the case, such as the 10-turn 10k Potentiometer used for the DART Linear Actuators where the sweep is on one side. Also remember, PWM cables have the voltage in the middle, and the signal to one side, with ground on the other, different from most potentiometers (but the same as the DART’s potentiometer)

The best way, as specified by @GeeTwo to verify is using a multimeter to measure the resistance values between the various pins with the potentiometer towards the middle to see which pin is the sweep.

As in your other thread, please post photos of both ends of the wiring.

In 35+ years working with such devices, I have never seen one get hot. When potentiometers go bad, they will go open circuit which cannot lead to heating. The only reason it can get hot is if it is connected incorrectly.

fixed the issue, I had the ground and the power mixed up :slight_smile:

Switching ground and power shouldn’t fix the problem, assuming the problem was truly that your wires were mixed up. All it should do is change which side of the potentiometer reads 0V and which reads +5V.

I’m glad to hear that it’s fixed though.

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