Modify example "Frequency Measurement.vi" for cFP to read two channels

I am using the cFP-CTR-502 to measure frequency on one channel using a modified version of the built-in example, "Frequency Measurement.vi" found under 'Hardware Input and Output>Fieldpoint>Advanced'. How do I modify this example further to incorporate additional frequency-measurement channels?

AEICincy,
Modifying the example for multiple frequency measurements shouldn't be too difficult. If you wish to use the same gating pulse, the only thing you need to do is set up a new channel in MAX (set it up the same way you set up the first channel as per step 3 of the instructions), set the counter channel on the new front panel controls, and add code to read and reset the counter (which can be copy/pasted in the False case of the code). I have attached an example of a VI with these changes.
Message Edited by Devin_K on 01-28-2008 08:38 AM
Devin K
Systems Engineering - RTT & HIL
Attachments:
Frequency Measurement.vi ‏106 KB

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Hello Ni Forum,
I already searched for similar problems, but haven't found anything helpful. So I'm posting our problem here. I'm apologizing in advance for bad english, it's not my mother tongue
We're encountering some strange behaviour of our NI9411 Module. We're using it in a Compact Rio with some other modules (2x Analog In).
Our goal is to measure the frequency of three flow sensors (impulse high = 24V, 0-22kHz) among with a torque sensor (TTL 5V, 30-60kHz) and a speed sensor (TTL 5V, 0-51,2kHz).
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LabView
ideal values
Flow Sensor 1
Flow Sensor 2
Flow Sensor 1
Flow Sensor 2
4600
12200
740,6
6760,0
6400
13500
1481,3
7500,7
9700
16400
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8982,0
12900
19500
4443,8
10463,2
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Puls-Measure-VI is attached beneath.
Regards,
Johannes Rost
Attachments:
vi.png ‏20 KB

Dear Lynn,
thank you for your reply. The impedance was an issue that our local technical distributor already suggested to check. According to the datasheet of the flow sensor (see attachement) it can drive a current of 25mA. The signal generator we used is a test generator that can be used instead of the flow sensors to check the any evaluation unit the sensor is connected with. So it should generate signals that are equal to those the sensor would have generated. And even with this the frequencies measured with LabVIEW are not as expected.
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Attachments:
block diagram signal amplifier and signal description.png ‏151 KB
technical data.png ‏124 KB

Modify example "Frequency Measurement.vi" for cFP to read two channels

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