Advice on how to check multichannel waveform data for if it exceeds different limits?

[Shiv0921]

Hello, I’m new to labview and could do with some advice on my approach.

I’m reading 5 channels (1 voltage, 4 temp) of continuous waveform data and want to be able to trigger a safe stop of my VI if the readings go above certain different values.

At first, I thought using the limit testing vi would do, but I need to be able to split the data and then apply different limits (voltage <10, Temp<80)

I’ve attached two vis which are the (similar) two approaches I’ve thought of. My issues with them are:

• I split the array of waveform data using an index array- can I be sure the channels split as I expect them to? (voltage first, temp after).
• Am I iterating through the data correctly- in a way where as the loops repeat I will check all data coming through?
• I don’t know how much data will be coming through at once, so I don’t know what to wire to N

Any advice would be much appreciated, thanks

Siobhan

(Data Error checking is where the VIs are, ETS P1 is the whole project, in case you need that to open it)

[Shiv0921]

I';ve worked some more on this and have thought of an additional way. but I'm not sure this is any improvement.

All of my data is sent to a waveform chart and i can select for indicators associated with the values of the separate channels to be visible. These don't have their own block diagram terminals (I suppose because they're related to the chart), but I can produce references to them. i can then use property nodes to repeatedly read these values, checking if they are above a certain limit and using case structures to act accordingly. 

Is this better? This way i can be sure I'm checking the right channels, but it would require using 5 property nodes to read continuously, and I think that would involve a lot of memory use?

[GerdW · Accepted solution]

Hi Shiv,

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@Shiv0921 wrote:

I’m reading 5 channels (1 voltage, 4 temp) of continuous waveform data and want to be able to trigger a safe stop of my VI if the readings go above certain different values.

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Just check for your limits:

[Shiv0921]

Thanks! I get a bit confused by indexing through arrays