6016 cold junction setup

Question

I am trying to use the 6016 to measure temperature in a chamber. I am aware that there is no built-in compensation network in there. So, my reading is all over.
I would like to use another thermacouple outside of the chamber as reference for the thermacouple that is inside of the chamer. I understand that the reference might drift a bit depending on the room temp, but at least it will be better than not using it.
How can I implement this? I using the DAQmx Assistant to do this. And at the bottom, where I set up the CJC, I choose channel but what do I type in there? 14 since reference channel is 14. I keep getting message saying that where is no such channel.
Or is there a better way to it? Can I place a know voltage in one of the ports to create a reference. Again, how to I tell the DAQ Assistance to use this as reference.

Answer 1

On Apr 21, 7:27 pm, hrh1818 <[email protected]> wrote:
> On Apr 21, 2:10 pm, randyram <[email protected]> wrote:
>
> > I am trying to use the 6016 to measure temperature in a chamber. I am aware that there is no built-in compensation network in there. So, my reading is all over.
> > I would like to use another thermacouple outside of the chamber as reference for the thermacouple that is inside of the chamer. I understand that the reference might drift a bit depending on the room temp, but at least it will be better than not using it.
> > &nbsp;
> > How can I implement this? I using the DAQmx Assistant to do this. And at the bottom, where I set up the CJC, I choose channel but what do I type in there? 14 since reference channel is&nbsp;14. I keep getting message saying that where is no such channel.
> > &nbsp;
> > Or is there a better way to it? Can I place a know voltage in one of the ports to create a reference. Again, how to I tell the DAQ Assistance to use this as&nbsp;reference.
> > &nbsp;
> > &nbsp;
>
> With you 6016 located outside of your chamber and your thermocouple
> located inside your chamber connecting a second thermocouple located
> outside the chamber to your 6016 will not gain any thing. The output
> from a thermocouple is proportional to the difference in temperature
> of the two junctions. In the setup you propose the two junctions will
> be at the same temperature and will produce approximately zero output
> voltage.
>
> If your room temperature variation is relatively small you could
> insulate the terminals of your 6016. The object of the insulation is
> to dampen short term temperature excursions. Another possibility is
> to use a temperature controlled oven to maintain your reference
> junction at a constant temperature. Frequently these ovens are
> operated at 150 degree Fahrenheit. A third possibility is a self
> powered reference junction. See.http://www.omega.com/ppt/pptsc.asp?ref=LXCJ&Nav=temk03
>
> Howard
Another possibility is to use a semiconductor temperature sensor to
measure the temperature of your cold junction and then use the output
of the sensor to compensate your thermocouple readings for room
temperature variations. See:
http://www.temperatures.com/semivendors.html for a list o vendors who
manufacture semiconductor temperature sensors.
Howard