Open Thermocouple Detection using NI 9148 with NI 9213 in scan mode

[JDavis644]

I am using the Ethernet RIO chassis NI 9148 with a NI 9213 TC module in scan mode. The issue is reading open thermocouple channels. My application reads channels that may or may not be connected and I need to be able to read open channels without generating an error. When using the USB RIO chassis with the NI 9213 using daqmx I do not have any issues (reading open channels). Is there a way to get around this open thermocouple detection error? I appreciate the feedback

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[Sam_Sharp]

Can you not just ignore the specific error code (-1950678943)? You can do this using the [exception] part of the general error handler or a case structure / select.

[JDavis644]

Thanks for the recommendation. Ignoring the error does work although I would love to be able to disable this feature.

[JDavis644]

Actually, there still is a problem with ignoring the OTD error. When using the "Open Variable Connection" .vi to setup the channel, if a T/C is not connected, this generates an error, which can be ignored. But after the read loop is entered, a T/C cannot be physically connected to this open channel with success. Now, if a T/C is connected initially and the variable connection is made, that T/C can be disconnected once in the "read variable.vi" and the OTD error can be ignored with success.

[Sam_Sharp]

You could always try to periodically re-initialise / re-open the thermocouples inside the loop? I wouldn't recommend doing it every loop period - maybe once every 10 seconds or so...or you could have a 'refresh' button so the user can initiate a refresh after they have connected thermocouples.