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Unread 07-02-2015, 21:47
Herbie_3633 Herbie_3633 is offline
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Can someone verify that I wired/am using this potentiometer correctly?

http://www.mouser.com/ProductDetail/...Rnf9DwYA%3D%3D This is the specific pot.

Terminals 1 and 3 are connected by a wavy line. Ground is going to terminal 1, power is terminal 3, and signal is terminal 2. Moving the pot with a voltmeter on signal and ground shows a change in resistance. The PWM is connected to channel 2 in the analog input. I've had the code verified to be working correctly, but the code will only output one value for the pot. Any sugestions?
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Unread 07-02-2015, 21:59
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Re: Can someone verify that I wired/am using this potentiometer correctly?

Quote:
Originally Posted by yash101 View Post
The other terminal is max resistance and should be left disconnected.

Code:
     5V VIN ->O<- N/C
              |
 Analog In (Measure)
This is not correct, the "other terminal" needs to be wired to ground.

OP, your wiring sounds correct. Can you use your voltmeter to measure the change in voltage on the signal pin when the robot is powered on?
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Unread 07-02-2015, 21:59
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Re: Can someone verify that I wired/am using this potentiometer correctly?

This is a circuit diagram of the pot. http://www.chiefdelphi.com/forums/at...9&d=1423324012
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Unread 07-02-2015, 22:03
Herbie_3633 Herbie_3633 is offline
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Re: Can someone verify that I wired/am using this potentiometer correctly?

Quote:
Can you use your voltmeter to measure the change in voltage on the signal pin when the robot is powered on?
What do you mean by this? Do you mean put one diode where the PWM connects to the RoboRio and one where the PWM connects to the pot?

Last edited by Herbie_3633 : 07-02-2015 at 22:36.
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Unread 07-02-2015, 23:10
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Re: Can someone verify that I wired/am using this potentiometer correctly?

Quote:
Originally Posted by Herbie_3633 View Post
What do you mean by this? Do you mean put one diode where the PWM connects to the RoboRio and one where the PWM connects to the pot?
You are attempting to use the roboRIO to measure the voltage on the signal pin of the potentiometer. Your voltmeter also measures voltage. With the robot powered on, measure the voltage between the signal pin and ground (whether you do so at the pot or at the roboRIO end is not important though I suspect the pot end will be easier). You should see ~5V at one end of the pot travel and ~0V at the other end.
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Unread 07-02-2015, 23:25
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Re: Can someone verify that I wired/am using this potentiometer correctly?

Quote:
Originally Posted by Herbie_3633 View Post
http://www.mouser.com/ProductDetail/...Rnf9DwYA%3D%3D This is the specific pot.

I've had the code verified to be working correctly, but the code will only output one value for the pot. Any sugestions?
If you are using LabView to program your robot you may wish to review the example labeled "analog input" to see how to implement analog readings in your robot. The example even includes a wiring diagram for a potentiometer.
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Unread 08-02-2015, 15:54
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Re: Can someone verify that I wired/am using this potentiometer correctly?

Between ground and signal I get a reading of 0 V, but between power and signal I get a reading of ~7 V.
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Unread 08-02-2015, 16:09
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Re: Can someone verify that I wired/am using this potentiometer correctly?

That doesn't make sense. If you have wired it to the roboRIO's analog input pins, there isn't 7 volts anywhere.

You have wired it to the roboRIO's analog input pins, right?
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Unread 08-02-2015, 16:16
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Re: Can someone verify that I wired/am using this potentiometer correctly?

Just tested it with another voltmeter and it is ~5 V the other one must have been bad.
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Unread 08-02-2015, 17:22
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Re: Can someone verify that I wired/am using this potentiometer correctly?

My question was not about taking a static reading on one condition of the pot. If Signal to Ground is currently zero volts, spin the pot to the other extreme, do you get a reading of ~5V? If not, there is a problem somewhere.
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