Noisy thermocouple signal with SCXI-1125

Hi all
Am using SCXI -1125, with 1328 terminal blocks, I have set the filter to 4hz in the signal conditioner. Am using 256 T type thermocouple, with 1 sample per channel at a very low sampling rate "1Hz".
Am receiving lot of noise in the signal, aprox +/- 1deg. But there are other channels which are very stable with hardly 0.2deg variation. I have tried connecting the negative of the noisy signal to ground, but with no results. Can anyone give some input on this?
Thanx a lot
Arun

Arun,
Are you sure you are setting these properties correctly? Before
modifying any of these properties, you must specify the active
channels. Please take a look at the attached example program. It sets
the active channels to all channels in the task and then sets the
auto-zero mode. A similiar process should work for enabling the filter
and setting the cutoff frequency.
Hope this helps!
Ryan Verret
Product Marketing Engineer
Signal Generators
National Instruments
Attachments:
Cont Acq Thermocouple Samples-Int Clk.vi ‏98 KB

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