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Use of counter NI 6612 to count no. of pulses per second

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Hi,

I am using an MCP detector which detects molecular ions. For each ion falling on the detector it generates a bunch of electrons by its mechanism. Due to that it generates pulses which goes as input of a constant fraction discriminator with pulse amplifier. This pulse amplifier gives me LVTTL signal as output. Each pulse in this LVTTL signal corresponds to one electron. My aim is to count the LVTTL pulses that occur per second which will let me know the number of electrons collected on an anode plate per second.

I have PCIe-6612 and PCIe-6323 with BNC-2121 and BNC-2090A terminal block. Is it possible to use any of these two as my counter which will show me the counts/sec, that means counts will be reset after showing the value at every second. Finally I want to take those values of counts/sec to plot a graph. If it's possible please explain the hardware connections and shortly the steps of LabVIEW code also.

I am a new user of LabVIEW and trying to learn it. After reading the manuals of PCIe-6612 and BNC-2121, I connected the LVTTL signal to the source (pfi-39) of counter zero, and tried edge count. Counter couldn't detect the input signal and so it didn't start to count. One thing I noticed that counter zero can detect this input signal if I connect it to pfi-37 (counter 0 aux) then it starts counting. Could anyone please clarify this. I am using LabVIEW 2018 version.

Thanking you in advance.

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Solution
Accepted by topic author Tanmo

I am unsure either way whether LVTTL signals are compatible with your devices or whether it may depend on your choice of spring terminal vs. BNC connection.

 

What you described sounds unusual to me -- were you using your own LabVIEW code?  I'd recommend you use MAX test panels to test basic count functionality.

 

Either of your devices are able to do the kind of measurement you want if you give them compatible signals and configure them appropriately.  In fact, either of them can do the measurement in multiple ways -- read your manual(s) concerning frequency measurement.  You can also do edge counting at a constant sample rate and calculate frequency after the fact.

 

But first things first -- make sure your signals are compatible and do your initial tests with MAX test panels.

 

 

-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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Hi Kevin,

Thanks for the suggestion. Yeah, LVTTL signal came out to be compatible with 6612 using BNC 2121. Now I am able to measure counts/sec as I described previously. 

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