We’ve been trying to use the 10k ohm linear taper for our steering mechanism keep burning out, we plug the 2 outer wires to the positive and negative on the pwm cables and also the middle wire to the middle wire, but for some reason we keep burning them out and also the values aren’t what they’re suppose to be, when i turn the taper half way and connect it the value of analog is 1000 and then when we turn it further to the right or left it starts to smell burnt. The thing is we had it working before, but then when we switched our robot back on it just burned out. If anyone can give any inputs on why it is happening or how to fix it, it’d be greatly appreciated thanks!
DarKCroNo,
If your potentiometer releases magic smoke only in certain positions, you most definitely wired it the wrong way. When you move the wiper to the “bad” position, you are shorting the RC +5V and GND pins, forcing a huge current into the potentiometer (large enough that it burns).
To wire it correctly, grab a multimeter and dial in so you are measuring resistance in the 20kohm range (it varies by model, just make sure it’s larger than 10kohm). Position the potentiometer slider about halfway through and place the probes on any two of the three pins (and by your description, it probably isn’t the outer pins). If the slider is in the middle and you manage to measure 10kohms (you said that’s the nominal resistance of your pot) in any two pins, that’s where you’re supposed to solder the red and black wires. The white wire is soldered on the remaining pin, the wiper. If you notice that the count goes up when you wanted it to go down (ie, sliding the other way) then you need to swap the red and black wires from what you had previously soldered. The white wire remains the same, of course.
If you need further help, or if my advice didn’t work, please ask again! :yikes:
Okay so as we turn the pot and if i connect the multimeter to the 2 outside pins, I see that 10 ohm’s is continually shown. Our teacher had said thats where the black and red wires, + and -, cuz the pwm cable the red wire is in the middle so for this argument we’ll say that black and red means - and +. so we connect the 2 outer pins and 10 ohms is continually shown no matter the position of the taper. But thats how we originally wired it.
Edit: I’m sorry I made a huge mistake, I had thought the PWM wires were the 2 outer wires were positive and negative but I looked again on the RC and its red and black are positive and negative. Sorry to bother you and thanks alot you gave me the idea to check!!
Al,
I’m pretty sure he’s connecting the potentiometer to the RC (he mentioned 10kohms, PWM cables, RC), yielding that his topology is correct but some wires are swapped!
You had it working before and when you turned the robot back on it just burned out, I assume powering it up. What did you do to or add to the robot in the mean time? Is there any chance that you are shorting out over your chassis by having a short somewhere else?