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NI6229 Channel range configuration

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I have a problem when I use the PCI_6229.The first channel collects millivolts,and the remaining channels collect  cell monomer voltage.So I want to set the first channel range is 0~1v,and the remaining channels range is 0~10v.How do I configure the Card in this situation?

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Hi bhyy,

 

have you tried to configure the DAQmxCreateVirtualChannel function for each channel as needed?

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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According to the spec sheet, the ADC is muxed; thus all channel gains need to be the same, if I understand the question correctly.

 

mcduff

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Build a simple x1000 pre-amp for Channel 1.

 

Bob Schor

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Solution
Accepted by topic author bhyy

You *can* configure distinct gains / ranges for the different channels.  Here's a snippet to illustrate GerdW's suggestion in msg #2.

 

 

-Kevin P

 

individual ai gains.png

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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Kevin_price is right, you can set different ranges per channel, BUT be aware you might get some ghosting after switching between channels, depending on your circuit's specifics.

 

I had an application where I needed to measure 15 channels in the 0-0.1V range, then a 16th in the 0-10V range, and I would see higher voltage than was real after scanning the 10V channel. (Note I was also scanning very quickly- a slower rate will help a lot).

 

Basically, if the muxed ADC is reading 9 V on something, then it needs to read 0.01 V, it will need some time to "bleed" down to that level. IIRC I was reading at ~50 kHz which resulted in ghosting on the first few channels. Just something to keep in mind.

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