USB 6008 Problem 1.4V

[dalvares]

Hi All, 

This is problem I can't really understand.

I am trying to measure an analog voltage using RSE input configuration. I get a constant voltage when nothing is connected. (this is normal I know). 

However, if I I try and measure the voltage drop across a resistor in a voltage divider circuit and I am still getting 1.4V ( I should be getting 0.5V because I am measuring it on the multimeter too). The voltage for the circuit is supplied from the 5V output of the DAQ. Could this be the problem or have I done some to the DAQ? 

Self test works ok 

Thanks

Darren 

[Tom__Sedlack]

Some things to check:

Make sure the DAQ ground is connected to the circuit ground. 

Make sure the wires going into the terminal block are electrically connected. I've had an occurance of the wire insulation being clamped and the wire floating inside the connector and not making electical contact.

Make sure you are reading the signal you intend to be reading and actually in RSE mode.  Again, I've been caught thinking I was reading one channel but the code was reading a different one.

[P.Sanders]

Check your wiring using this link. Also, if you supply a known dc voltage to the DAQ are you getting correct readings?