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Using ULx for MC USB-1408FS

I am using ULx for MC USB-1408FS to record data from two transducers via two separate channels. How do I record the data simultaneously from both channels? Currently I can view only 1 channel data at a time. I have just started using LabVIEW and am using the existing VI from the ULx library. I am currently using the ULx Cont Acq&Graph Voltage VI.

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Since this library is not developed by National Instruments, it is difficult to say how this is done without looking at the code.  It would help if you posted the code you are working from.  If you were using DAQmx (the device driver for National Instruments data acquisition hardware), you would just choose multiple channels when you create the task then change the DAQmx read function to "Multiple Channels" when the data is read.  This is shown below:

 

DAQmx Multiple=

 

This may or may not be a similar process depending on the drivers that the ULx library uses.

Zach C.
Field Engineer
Greater Los Angeles

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The part which you have displayed works fine showing both output voltages from both channels. I later average values and display them on a different screeen below. Although both averaged values are seen in the data file only a single channel voltage is displayed after being averaged. How do you display voltages from both channels after being averaged? 

 

Thanks,

 

Rohan

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You are converting the blue dynamic data type wire to a single double.  (how do you like that combination?)  So you only get a scalar value.  You need to use the From DDT function in the Express palette to convert the blue data type wire to an array, then index out the individual elements of the array.

 

That or use the split signal function on the blue wire coming out of the statistical espress VI, then convert each of them to a scalar value.

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The VI I am currently using was built to gather data from a single channel and it works fine. I am trying to modify it so it can be used to record data from two channels. Will look at using DDT and take it from there.

 

Thanks!!

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