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FPGA not writing voltages correctly

I am using a cRIO 9035 with modulus NI 9264, 9205, 9213, 9401, 9344 x2.

Here is what my FPGA code looks like:FPGA.pngAs you can see the "Tube_Air_MFC" is wired to AO2 and the "MFC_Tube_Air" is wired from the AI2. I attached the current project that I am working in, if you run the initialized values you will see that the Air Set value will read  ~14.37 which will correspond to the flow rate of the tube air. FrontPanel.PNG

 

 

It should be outputting 14.37/15 = 0.958V, instead though my multimeter is giving me a reading of 0.331V. Since my analog output is wrong then the analog input is wrong too, so the actual air value is completely off. 

 

Sticking with the same analog device, I am using a SmartTrak CL100 mass flow controller at the AO2 position. It has a voltage reading of 0-5V and a flow rate of 0-75 SCCM, hence the voltage conversion of dividing/multiplying by 15. The NI-9205 terminal is set to +/-5V with a differential terminal.

Here is what the wiring looks like

20180809_152133.jpg

 

I kept getting phantom voltage readings from the NI 9205 so I just grounded all the terminals that were not being used.

 

 

 

 

 

 

 

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Anybody have any clue? I tried setting a larger wait time, but that didn't seem to do anything

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What does the output rad with just a meter connected and no load connected?

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
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@Ben wrote:

What does the output rad with just a meter connected and no load connected?

 

Ben


If there isn't any voltage being sent then the readings are small decimals (i.e. below +/- 0.25)

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@atokad wrote:

@Ben wrote:

What does the output rad with just a meter connected and no load connected?

 

...


when;

 

"

It should be outputting 14.37/15 = 0.958V,

"

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
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It was ouputting 0.331V whenever the calculation should've been 0.958V.

 

Now since I changed the wait time, it looks like there is actually 0 voltage output.

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I am headed home in 14 minutes...

 

If you do what I asked before then I may be able to help further but after that you willhave to forget about me being able to help.

 

Run the code again "whenever the calculation should've been 0.958V. " do not mess with anything else except pulling wire off of the terminal block.

 

12  minutes now.

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
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@Ben wrote:

 

Run the code again "whenever the calculation should've been 0.958V. " do not mess with anything else except pulling wire off of the terminal block.

 


Which wire on the terminal block? Are you referring to the module or the code??

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the physical wire get disconnected and attach a meter where the wire was connected.

 

There could be an issue with the load you are driving...

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
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That gives me a voltage reading of .290V

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