AI Acquire Waveforms High and Low Limit

[Devon Jedamski]

Hey everybody,

I am currently working with Labview 7.1 and a daq card. I am collecting 4 channels and using ai acquire waveforms to do this. I want to have different high and low voltage limits for each channel though. Is there a way to do this with ai acquire waveforms or would can I use something else.

Thanks for the help!

Devon

[Davidek]

Hi Devon

I'm guessing that you are using Tradition DAQ and not DAQmx, can you confirm this? Also, are you talking about the acquisition settings when you say high and low voltage limits or some alarming mechanism? Would be great if you could post an example VI so we could see what you are doing.

Best Regards

David

NISW

[Paul_C.]

Hey Devon,

In addition to what David said, there is a great knowledgebase article here with more information about setting multiple ranges for Analog Input.  The Traditional DAQ vi, AI Acquire Waveforms, doesn't expose the ability to set multle input ranges per channel, but there is a quick fix that you can do to be able to add it to the vi.  See below:

The block diagram of the AI Acquire waveforms is as follows:

As you can see, the inputs of the vi that are exposed are simply the first element in a array of clusters including the high and low limits per channel.  To set the high and low limits for other channels, you need to simply add another element to the array for channels 1, 2, and 3.  See below:

Here you can see I simply added one element, you need to add 2 more for your 4 channels.  If it turns out that you are using DAQmx and this doesn't apply, please refer to the knowledgebase above for details and an examples on how to set different ranges.

Regards,
Paul C.

[Devon Jedamski]

I apologize for the extremely late response but thank you for the help.

I am using Traditional DAQ and your figures have shown how to fix the problem.

I appreciate it,

Devon