Signal Conditioning

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SCXI-1100 and Linear Motion Potentiometers

I am trying to configure a linear motion potentiometer on the SCXI-1100 with a 1300 terminal block. My first problem is that my voltage readings are all screwed up. When I just try to measure the voltage by putting the positive lead on CH0+ and the negative lead on CH0-, interesting things happen.
When my voltage source is off, it gives a reading of 10V. When it is on but turned down all the way, it is unstable with peaks but no troughs. When it is turned up just a little bit (not nearly 10V). It jumps to 10V.
To connect my potentiometer, I run the voltage across the whole thing and then put the middle wire into the positive channel input and put the negative channel input common with the negative voltage source.
I don't touch it, the signal is pretty steady close to zero. When I move the shaft a tiny bit, it jumps up to 10V and stays there the rest of the way in. This happens reguardless of whether my voltage source is set to 10V.
I tested my voltage source with a multimeter and it is working correctly. I believe I have all the wiring right, but there may be something that I have missed (I am very new at this). If anyone can help, I would appreciate it as I have been working on this for a very long time with no success.
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Hello, It's me again. I was a doofus and was working on channel 8 on accident. However, I don't know if what I have now is right.
I get readings with my voltage and with the potentiometer, but on the test panel they show up like a sine wave rather than a steady line. The result is a very noisy signal. I am not sure about the jumpers and if I have to change any of those. Right now I believe they are on the factory settings. Is this normal, or do I need to fix something. The reading straight from my power source is also wavy.
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Please keep in mind that the test panel tends to autoscale and zoom in to your measurement. This can make a straight line look like a sine wave (or a noisy signal) because it is zoomed in so far. What is the average reading MAX is showing? If you turn autoscaling off and change the graph limits to +/- 10V, how does the measurement look? If it still looks noisy, how much noise are you reading? 1mV, 10mV, 1V?

The SCXI-1100 includes both 4Hz and 10kHz filters. Once you determine the frequency of the noise you are receiving you may want to consider using one of these built-in filters. The 4Hz filter is excellent for removing common 60Hz noise.

Also, check out the following Application Note on wiring and noise. It is a great referen

Field Wiring and Noise Considerations for Analog Signals

As for jumper settings and other related questions, the SCXI-1100 User Manual is the best resource. You can find all manuals online at

Justin Britten
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