different types of sensors in the same SCXI module

[Dunty]

I am trying to use the same SCXI 1100 module to measure temperatures from 2 different sources. One source uses E-Type of thermocouples while the other uses K-type of thermocouples. I will be physically connecting the 15 E type of TC's in the 0 to 14 channels of the SCXI-1100 module and the 5 K-type of TC's in channels 15 to 19. I have two questions. First, how do I take care of the different types of thermocouples. What I tried to do is to scan the two set of channels (E-type and K-type) separately as you can see in the attached vi. However when I specify the list of channles to scan as ob0!sc1!md1!0:14 (for E-type) and ob0!sc1!md1!15:19 (for K-type), I get some "Error - 10001 at AI-Config group" error. When I change
the channel list for K-Type of TC's to
ob0!sc1!md1!20:24, I do not get the error. Can you tell me why ?

My next question, is there a better way to do what I am doing, I is it really necessary scan the different set of channels differently ? Also I am expecting to see a array of 15 (for E-Type) and 5 (K-Type) number when I as an output, but I see only one element for both of them, any reasons why thats happening ? something wrong with the vi ?

Thanks a lot !!

Dunty

[RIO-Todd]

The best and easiest way to program your application would be to use virtual channels in Measurement and Automation Explorer (MAX). Within MAX, you can create a virtual channel for each thermocouple (will work with both E and K type thermcouples) and when running a basic analog input VI (Cont Acq & Chart (buffered) VI for example), you can use the virtual channels for the channel names rather than the long SCXI-channel string. The document linked below goes into more detail of creating virtual channels. I hope this helps.

What Is a Virtual Channel? How Do I Create One?
http://digital.ni.com/public.nsf/websearch/31C55E253B023189862569850068B8AE?OpenDocument

Regards,

Todd D.
NI Applications Engineer