How to measure voltage?

Equipment used:
- Connector Block CB-68LPR
- DAQ Board NI6013
- VI Logger
- Pressure tranducer (runs on 5V)
What am I trying to do:
- Connect pressure tranducer to connector block, so I can display measured voltage in VI Logger.
What I have done:
- Pressure tranducer has got -Vin +Vin +Vout. I have connected +Vout to AI ch0 and -Vin to AI ch8 (differential).
- In VI Logger, I have created virtual channel that is reading Voltage (max 50V, min -50V).
The problem I have got:
- VI Logger is reading 5V all the time. The voltage should increase/decrease lineary as the pressure is increased/decreased
but it doesn't. It is always 5V that is not true. I have tested the device in the test panel and Vout (ch0.) is always 5V exact.
How
to solve this problem? What and how should I check, have I connected everything properly?
Thank you.
Regards Slav.

I had a similar problem. I changed the input from differential to single ended and it works. You need to connect your V- to Agnd. Unless there is a reason you need to read differential...thermocouples that I set up work fine in differential but there is no common ground to a voltage source.
Make sure you have set up the Virtual Instrument in MAX properly. Good luck.

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To whom it may concern:
I would like to post this question here so that it is easy to understand.
I would like to ask how 6250 measure the voltage using AI+ and AIGND. One of your collegue told me there is no current flowing to Rin if AIGND = Vs(0). I am trying to measure 100ohm resistor using AI+ and AIGND. I used DMM to measure from the top the resistor to AI+, the current was 0A and measure the current from the bottom of the resistor to AIGND. The current is 0A.
In fact, how 6250 measure voltage . If you put DMM instead of 6250, there is current going through DMM and you can show voltage. How about 6250. Could you please tell me?
I have attached a picture to let you understand what I mean. and where I got the information.
Here is the link
http://zone.ni.com/devzone/conceptd.nsf/webmain/D59654FA44D2F9FA86256F4A006064F3
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Hello LochiMD,
there are sereral things you have to care about.
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https://decibel.ni.com/content/docs/DOC-12182 (Have a look on the picture, especially left side)
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Best Regards,
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Read this Tutorial
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Message Edited by kuroshio on 07-11-2005 10:49 AM
Message Edited by kuroshio on 07-11-2005 10:55 AM

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Hello LochiMD,
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