SCXI 1303

[iganghel]

Hello,
Here, there are few details about my systems. Basically I have 3  SCXI1303 with a total of 96 channels and 1 SCXI 1320 with 8 channels. They are disposed in a sassy SCXI-1000. We use SCXI 1320 to get measurements for voltages and SCXI1303 to get measurements for temperatures.
From SCXI 1303, we are using 88 channels (40 can be seen on the white line of the graph and 40 can be seen on the red line of the graph) for measurements of the wall temperature (as can you see in the graph) and the others until 96,  to measure coolant temperature. The thermocouples are K type manufactured by Omega company and they have a precision of 1.2 C. We suppose to take measurements  in a range from 20-800 C. As you can see in the picture, couples of the thermocouples have wrong indications.  As soon as we rise the electrical power (i. e currents through the pipe walls), the thermocouples represented by the red lines  have  totally wrong indications (the pictures from attachment are not the worse one!).  We suspect the reason for these failures are SCXI 1303. Does any one of you has this problem? How can be solved? I know that SCXI 1303 has not galvanic isolation. Could be this a reason?

Thank you,

Ionut Anghel

[Christian Mergl]

Next time you should post that in the "Multifunction DAQ" forum.

However, I would suggest you to contact your local NI Office on that to see if you might get another 1303 to check if its not a problem with yours.

Christian