USB-6001 output voltage does not go above 0.8V

[Sorosham]

Hi all,

I just  received my NI 6001 and wired the connections to send output analog signal to a pressure regulator and receive input signals from the pressure sensor simultaneously. Labview 2018, DAQ driver 18.0

The issue is that although I control the output voltage to be 5V, the actual voltage does not go above 0.8, however between 0 and 0.8 it works correctly. I set the I/O voltage range 0-10V using DAQassistant which is according to the specifications of the pressure regulator. 

Can you please help me? many thanks!

[James.M]

Please include a Snippet of your code, or attach your VIs, so that we can better assist you.

Also, you may need to supply a picture of how you have it wired. How are you measuring the 0.8? Is it from AO1 or AO2 to AO Gnd?

[GerdW]

Hi sorosham,

how much current draws your pressure regulator? Is it beyond the specs of the USB6001?

[Sorosham]

Thanks for you reply. 

I attached a photo from wiring and also the Snippet. 

I measured 0.8 by reading the feedback signal (wires black and orange), and also directly measring by multimeter.

[Sorosham]

Thanks for your response. When I make no change to the output signal it shows 0.13A, and when I change the output signal it goes up to 0.15A,

I could not find the nominal range of 6001 current, unfortunately.

[RavensFan]

http://www.ni.com/pdf/manuals/374369a.pdf  Page 2.  Output current is limited to 5 mA.  I don't see how you can possibly be getting to 130 or 150 mA.

So what is the resistance of the circuit you connected to the analog outputs?  If the resistance is too low it won't be able to source enough current to have it maintain a 5V output level.

Read the specs for your pressure regulator.  Attach them as a PDF to this message thread if you need to.

[Sorosham]

Thanks for the response. Maybe the wires I used have very low resistance?

Pressure regulator datasheet is attached below: 

[RavensFan]

Wires generally should have low resistance.  It is not that.

The spec sheet says it has an input impedance of 100 kilo-ohms.  So a 5 VDC output should only draw about 0.05 mA.  So that shouldn't be a problem.

I would check to make sure you have it wired up correctly.  Check to see if you have any shorts.

[Sorosham]

Thank you, 

I reported the 0.13A from the power, as it's in the picture. I guess the wiring should be fine, however the way I attached wires were just by winding, this might have caused loose connection?

Best regards, 

[RavensFan]

That picture shows a power supply and the 6001.  Where is the pressure regulator?

And that .13A is the output of the power supply.  It is not the current coming out of the analog output.

Show a picture of the actual wiring diagram, not just a picture of a bunch of wires.