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calculate startup time with Compact Rio

Hi there.

My company recently purchased some NI CompactRIO devices. 

I have a product that output analog signals for voltage and current.

When the product is programmed to a specific voltage and current, I would like to record how long it takes for the voltage and current to stabilize.

The startup time should usually ranges between 800ms and 1100ms.

Right now I am using DAQmx to trigger data acquisition on a digital edge and then graph it. That works just fine.

My question is how can I start a timer when data acquisiton starts and then stop the timer after the voltage has stabilized (i.e. after 500 stable sample points).

My code is based off one of the NI examples so it very basic. I have attached my VI.

I know there are counter/timers available but I'm not sure how to implement this. And I dont know how I would display on the x-axis of my graph the startup time in milliseconds. 

Any advice or tips would be greatly appreciated! Thank you!


What I have:

cDAQ-9174 CompactDAQ chassis (4 slot USB)

NI9205 32-Channel Analog Input Module

NI9264 16-Channel Analog Output Module

NI9401 8-Channel Digital IO Module 

Don't think twice.
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Message 1 of 5

Hello, take a look at the attach VI from this community example. Make your stabilized voltage/current level the stop condition for the loop to obtain the elapsed time. I hope this works for you Smiley Wink

Alejandro C. | National Instruments
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Message 2 of 5

thanks for the information, it does help. I was wondering if I could the same with DAQmx VI's and compactRIO? 

Don't think twice.
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Message 3 of 5

Unfortunately DAQmx and CompactRIO don't mix, however, the idea for the bechmarking remains the same indifferent to the programming.

Alejandro C. | National Instruments
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Message 4 of 5

ok.thanks. How would I tie in the time into my graph?Is there a way?

Don't think twice.
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