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Cannot get signals of potentiometer

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Hello,

 

I connected 3 potentiometers to 3 channels, seems like only the first one works fine (the data curve looks like a horizontal line before move, straight line with slope during move, horizontal line when stable). The second channel gave me the signals with little vibration before any move, so I cannot decide which number is the initial value before any move. The third channel turned out to give me horizontal line during the whole process.  I thought it might be some problems with the channels, so I connected my potentiometer to another channel, which still gave me horizontal line this time. I have no idea why this happened, could someone help me with this? why can't I get any signals after the connection of potentiometers?

 

Thanks.

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Do you mind to show your VI and your data?

How did you connect those pot's?

Did you follow MAX' advice on wiring your signals?

Best regards,
GerdW

using LV2011SP1 + LV2017 (+LV2020 sometimes) on Win10+cRIO
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Are these virtual potentiometers?  How can they generate signals?  Are you even talking about LabVIEW?  

LabVIEW 8.5.1 - 2019 Pro Dev
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Actually, the potentiometers were connected by one of my groupmates, he said they all worked fine and he already used them doing his test a couple of month ago. But when I test the potentiometers this time, it doen't  look fine to me. I kind of fixed the potentiometer, clicked the run bottom on the front panel, then immediately I pull the string to let it go to 1inch in order to check if it works. I may need to double check if the wires of the potentiometer were correctly connected first, I think. 

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It's not virtual potentiometer and I programmed in Labview. I kind of fixed the potentiometer, clicked the run bottom on the front panel, then immediately I pull the string to let it go to 1inch in order to check if the potentiometer works.

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OK if you are talking about real physical potentiometers, there is also the question of how you have them wired to your IO ports. And come to think of it, what flavor of ports you have them connected to.

Mike...

Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion

"... after all, He's not a tame lion..."

For help with grief and grieving.
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Please tell us what DAQ device you are using and post your VI and any custom subVIs. If possible, please show some data. Run the VI. Stop it when the data shows on the graphs. From the Edit menu choose Make Current Values Default. Save the VI and post that version.  Without that information we are guessing about your problems. Once we see the code someone will probably be able to suggest a fix.

 

Lynn

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Hello,

 

The module I use is NI SCXI-1315. This morning I found out some of the wires in the connection broken, I think that might be the reason why I got horizontal line from some channels.

 

The attachment are the VI and some data I got. I let the string of the potentiometer move 1 inch, but still the result is much less than 1 inch.   

 

I also checked MAX, looked at the connection diagram. I noticed that four wires from CH+, CH-, EX+, EX- should be connected to the potentiometer accordingly. But I have 6 pin connections of my potentiometer, they are +In, Common, +out, no connection, no connection, no connection, respectively. My groupmate wired CH+, CH-, EX+, on the module to the 3 connections of potentiometer, then use a wire to connect CH- to EX- on the module. I don't know whether this is a right connection or not.

 

Another problem is that the maximum and minimum value in the front panel cannot be set as I expected, I have to set them as the device range then I can get signals, any solutions to this?

 

Thanks.

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Message 8 of 15
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In addition to the 1315 terminal block are you also using the 1340 LVDT module?

Can you show how you have the potentiometers wired to the channel inputs. You stated the three connection that were made to the potentiometer, but didn't say which one connection went to which terminal. Also what potentiometers are you using?

Mike...

Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion

"... after all, He's not a tame lion..."

For help with grief and grieving.
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Hi, Mike,

 

I just used 1315 terminal block. +In connection to terminal EX+, Common to CH-, +Out to CH+.

The potentiometer I am using is PT1A-15-UP-500-M6 from Celesco company.

 

Thanks.

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