05-06-2009 02:37 PM
Here's my setup:
32 K-type thermocouples (mixture of grounded sheathed and ungrounded exposed tip)
TC-2095 rack mount thermocouple connector block
SCXI 1102c module
I am having an issue of stairstepping in the thermocouple data I am getting. The system seems to be sampling at the 500-1000 Hz sampling rate because noise and gentle sloping is recorded in the tc data in between the major jumps in temperature. The stairsteps generally occur at 1 or 2 Hz. The only thing I modified on the hardware was swapping in the 10 Mohm resistor packs into the tc-2095 to prevent a grounding issue from ruining the readings from our grounded thermocouples. Any thoughts on how to fix the stairstepping?
Thanks,
Alex
05-07-2009 01:18 PM
Hey,
Did this work without the10Mohm resistor pack?? Did this ever work?
You say you have grounded thermocouples---what are they grounded to? Can you expand on this setup.
How did you configure the dip switches on the TC-2095 for each thermocouple? I'm referencing the settings mentioned in table1 of the tc-2095 specifications sheet. This is found on page 5-6 of thespecs manual: http://www.ni.com/pdf/manuals/321731b.pdf
Can you attach a screenshot of the data that you are seeing so that I can inspect it. Also what sampling rates are you specifying? how are you programing this (Labwindows/labview?? etc... )
Please post back with this info so we can work to resolve this issue thank u