Measuring Multiple channels at a time

Hello All,
I am new to Labview trying to measure voltages and currents from a
synchronous generators using LabView7.1 abd PCI-MIO-16E-4. I want to
measure all the three phase voltages all at a time so that I can see
the phase difference between them. I modified an example for my purpose
but it can measure only one channel at a time.
Anyone please look into my file and modify it for multiple channels.
Thanks in advance
Venkatgill
Attachments:
Cont Acq&Graph Voltage-Int Clk.vi ‏330 KB

Let me explain. Your board has a single A/D. There is a mux that rapidly switches between channels. It will take a sample from channel 0, then channel 1, then channel 2, and then start all over again. It will repeat until the total number of samples that you requested have been taken. The switching is very fast - on the order of usec, so you can take the 3 measurements but it is not truly simultaneous. Depending on the frequency and the accuracy of the phase difference you're looking for, this may not make a difference. You can also get the inter-channel delay and compensate for it.

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Attachments:
Single Point Peak Valley Log_Mod.vi ‏53 KB

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Attachments:
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Attachments:
AI_AO_2 Counter.vi ‏153 KB
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Attachments:
Apply Calibration One Channel.vi ‏138 KB
Initial.txt ‏1 KB

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Attachments:
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Attachments:
project.vi ‏207 KB

Hi thanks those tips. In fact I had solved those problems mentionned above ; I have alomst finish my interface except that I am trying to write all my datas in a file , in column (all channels) and create a first column at the time (maybe from the sampling time). The problem is that I don't know the output fomat of the "analog 2D DBL" vi and it seems that my way of writing datas time step per time are not right. have you already see this kind of used (analog 2D DBL)? I am using a PCI-6229, and DAQmx 7.3 Drivers
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Attachments:
project_acquisition.vi ‏338 KB

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Attachments:
scope measurement.PNG ‏63 KB

How are you currently doing it? Personally, I would use a FOR loop to read the data from the two channels. It there is a function available, read then as a waveform data type. You can then wire the array of waveforms to your graph.
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I posted this in the podcasting forum, and it occurred to me I might have better luck getting a response here. Apologies if you've seen this one before! I quote:
I have a feeling this is a stupid question, but I'd hate to go without asking, so... I'm using a Behringer Eurorack UB1202 with a Behringer F-Control firewire interface to record a podcast with 3 (sometimes 4) microphones. Is there a way I could use that setup to split the audio onto 3 (or four) separate tracks? I'm assuming the answer is "no," since it ultimately dumps into one firewire input and therefore (I guess) one signal. I imagine I might be able to split off left and right channels, yes? But with 3 mics, that would put one on one track and two on another? (I'm using an iBook, by the way, so I've only got one firewire port to work with...)
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..just because all the signals go
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Assuming you are using the DAQ Assistant and getting one sample per scan, then you just use the Split Signal and wire the outputs to your indicators.
Message Edited by Dennis Knutson on 04-30-2007 09:49 PM
Attachments:
Split Signals.PNG ‏4 KB

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Hello,
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Attachments:
modified Magnetstriction.vi ‏96 KB

Hi
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Measuring Multiple channels at a time

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