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Testing a device in labview? how?

I'm pretty new to LabView. I'm wondering if I can test SCB-68 in labview. I'm wondering if it works properly or does the output signal has noise.. is it possible? Maybe using Measurement & Automation? Thank you

 

ETA: I can't find SCB-68 in device list for Measurement & Automation 

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Message 1 of 17
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An SCB-68 is a connector block, not a data acquisition device. What device do you have connected?

You can check what devices are connected and usually test them in NI-MAX.

Troy - CLD "If a hammer is the only tool you have, everything starts to look like a nail." ~ Maslow/Kaplan - Law of the instrument
Message 2 of 17
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Our AD board. I'm trying to figure out where the noise comes from in our system . We replaced the boards and now I'm wondering how to test if the output from scb-68 has noise or not 

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Message 3 of 17
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An SCB-68 is just a connector block. http://sine.ni.com/nips/cds/view/p/lang/en/nid/1180

It doesn't actually do anything except provide convenient connections point to a data acquisition device.

It could be connected to all sorts of different things. You need to tell us what device your SCB-68 connection block is connected too.

Troy - CLD "If a hammer is the only tool you have, everything starts to look like a nail." ~ Maslow/Kaplan - Law of the instrument
Message 4 of 17
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See we use bertec force plates for our research. The out out of Force plates goes in to amplifier , then out put of that goes to Ad board and then then scb-68 and then computer . We tested the signal up until ad board there is no noise but when we run our Force plate on computer ( labview program ) the out put has lots of noise. We replaced the ad boards ... now I'm wondering what to do

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Message 5 of 17
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There must be one more thing between the SCB-68 and the computer. That's the important thing.

Please open up NI-MAX, expand the "Device and Interfaces" item in the tree view, take a screen-shot of the list and post it here.

 

What do you mean when you say "AD board"? Is this some sort of Analog to Digital converter?

You need to provide more details about the setup in order for someone on this forum to be able to help.

Model numbers etc.

Have you verified the signal between the "AD board" and the DAQ connector? Can you provide a basic block diagram of your setup and an indication of which points you have verified and how?

Troy - CLD "If a hammer is the only tool you have, everything starts to look like a nail." ~ Maslow/Kaplan - Law of the instrument
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@CanucksGirl wrote:

See we use bertec force plates for our research. The out out of Force plates goes in to amplifier , then out put of that goes to Ad board and then then scb-68 and then computer . We tested the signal up until ad board there is no noise but when we run our Force plate on computer ( labview program ) the out put has lots of noise. We replaced the ad boards ... now I'm wondering what to do


And when you tested these parts, did you disconnect them from the others and try with/without the program running? It could be a ground current in shielding or similar.

/Y

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For some reason screen shot doesn't attach . But under device and interface it is NI-PCI-6225 dev1

i also wanted to thank one more time from all you for trying to help me. I'm new to my job ( I'm a new grad) and I really appreciate your help

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Message 8 of 17
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my screen shots

Download All
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Message 9 of 17
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OK, that is some very useful information.

According to your screenshot your signal is hooked up to a 6225 multifunction DAQ and is connected to ai0 in a "differential" configuration.

  1. When you measured the output of the "AD board", did you measure it at the terminals indicated in screenshot test1.png? At terminals 68 and 34?
  2. Does the chart in test2.png show the "noise" you are referring to?
  3. What sample rate are you using?
  4. What is the signal supposed to look like?
  5. Are you sure the task in your code is configured to measure a differential signal and not RSE or NRSE?
  6. Are you sure it is connected to the correct terminals?

I'm asking these questions because that doesn't look like noise, it looks like one of the terminals is floating (not connected to the correct location for the reference type configured).

 

Some more info on RSE/NRSE http://zone.ni.com/reference/en-XX/help/370466AD-01/measfunds/refsingleended/

 

Troy - CLD "If a hammer is the only tool you have, everything starts to look like a nail." ~ Maslow/Kaplan - Law of the instrument
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