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thermometer vi trouble getting readings

Dear Labview Users,
 
         I was following the thermometer vi on the cnx.org website and I am having issues getting a consistent reading from my thermocouple. The tutorial tells us to get a voltage input from the thermocouple so I put the leads of the thermocouple into the pins labview designated for sensing the voltage. It says to leave it in differential mode and so I did that. The problem I am having is that when the differential amplifier is connected to ground the thermocouple reading does not change. When I do not put in a reference ground the thermocouple readings go haywire but gives some kind of reading when I touch the thermocouple even though it is off by hundereds. I am guessing that how I physically hooked up the thermocuple to the board could be the problem or maybe there is some sort of filtering icon missing that I need to put in. I am using a daq 6016.
 
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Hi there,
 
It sounds like you need to place some bias resistors between your differential inputs and ground. So hook up your thermocouple inputs to their respective 6016 input channels (eg. one input to AI0 and the other to AI8) and then place bias resistors between those two input terminals and the GND channel.  For more information on input connections and ground returns, refer to this tutorial:
 
Regards,
Way S.
NI UK Applications Engineer 
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