Error -200088 occurred at DAQmx Timing (Sample Clock).vi:4730001 - How do I fix this

[T.Entwit]

I am setting up from a example program a custom scale VI to run (4) Strain-Gaged Extensometers (From Epsilon technology Corp. Model: 3575-200T-ST), and one Loadcell (Honeywell, Model 3674-20K), each setup on a Full Bridge Circuits using (2) NI9219 DAQ on my NI cDAQ-9718 Dock.  The custom scale I found originally through NI DAQ assistant to work well with the extensometers, converting the [mV/V] input signal and scaling it to a 0-.20 [IN]. But now that I have built a NI DAQ.mx VI for the custom scale, it does not appear to want to work as it should, due to the Sample clock possibly not being configured correctly?

[aputman]

I can't open your VI but after doing a Google search of the error code, other posts on the forum and articles in the Knowledge Base seem to indicate that this has to do with a lost task handle, that the task may have been initialized but the reference to the task was lost at some point, maybe in a case structure where "Use Default Value if Unwired" was used instead of wiring the task thru all cases. 

[JÞB]

Please post a snippet of the code.

I would also check for any 0 iteration For Loops and any other autoindexing surprises. 

[Bob_Schor]

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@JÞB wrote:

Please post a snippet of the code.

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Or open the VI and "Save for Previous Version" (I recommend 2021 or 2019).

Bob Schor

[T.Entwit]

This file has been saved as LabVIEW 19.0. And I have also saved a screenshot of  the block diagram here.

[GerdW]

Hi T,

so there are empty array controls and you wonder about the autoindexing FOR loop not working as expected?

(Well that loop really does work as expected!)

[T.Entwit]

Its been a while and just now have been getting back into the saddle with LabVIEW. So, what do I need to change, the FOR Loop with autoindexing is the correct way for each sensor to have its own set of pre and post scaled values correct? and then what about the empty array controls, I thought all of them are selected some may be bogus values, as at the moment, I only am using 4 Extensometers, and one Load cell,  each with the intention that I can use this full bridge custom scale, user selected, per each physical channel, from the front panel. My goal here was end result the waveform graph to show each signal post scale output.

[GerdW]

Hi T,

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@T.Entwit wrote:

I only am using 4 Extensometers, and one Load cell,  each with the intention that I can use this full bridge custom scale, user selected, per each physical channel, from the front panel.

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Then your array controls (in the "Scale settings" decoration area) need to hold 5 elements each!

Right now they are empty…

Or to put it in other words:

When your users should be able to select all those values on their own then it's your task to check ALL INPUTS for valid values. An empty array is not considered "valid input" in your case…

[Kevin_Price]

Looks like JÞB's magic 8-ball came through again!

If *any* of your 7 auto-indexing arrays are empty, your For Loop will iterate 0 times!  (Suggestion: make a cluster containing the 7 items, then make an array out of *that* to make sure you always have the same # elements of each item.)  As posted, the default values for *all* of them are empty arrays.

And if your For Loop iterates 0 times, your task and error output tunnels will carry their default values.  That's where your invalid task is coming from, just as JÞB  predicted!

Note that aputman's prediction is also a generally likely suspect, and a good one to watch out for in the future.

-Kevin P

[T.Entwit]

How do I change it to a fixed number of array control elements instead of an "open" unlimited amount of them. I thought this was accomplished as the channels not being used. would not be relevant although the signal would still be captured and scaled per the values 0 to 0 or what ever was defaulted for each.

selecting 1-8 for the available channels in the front panel scaled unit array control box down here. which I assumed auto indexed into the FOR loop accordingly Channel 1 though 8 or 0 to 3 on the first NI 9219 and 0 to 3 on my second NI 9219 each plugged into my NI cDAQ-9178