how to read pulse from digital square wave

[lim25]

hi,

recently i have bought a flow meter from blue-white. I have succefully read the digital square wave from the sensor. However, i face some problem to calculate the flow rate and the total volume of the liquid. Can anyone help me on this matter?

The flowmeter technical data can be access at http://www.blue-white.com/Products/ElectronicFlow/MicroFlo/80000-406_microflo.pdf. And the calculation can be find at page 9. I am using NI9401.

Thanks

[sahil]

hi lim

           i do not understand what actually you want to ask ...do you have the calculations problems or some problem related to its programming?please do explain a bit.

thanks

do not hesitate to give kudos

[Baji]

I cant able to poen the above mentioned link(http://www.blue-white.com/Products/ElectronicFlow/MicroFlo/80000-406_microflo.pdf.).

[sahil]

hii baji

            you are just having the problem with the (.) sign

            just click here and you will get that manual 

[lim25]

 hi ,

My objectives are to measure the flow rate and the total flow from the flow meter. Since i am new in DAQ, i don't know how to calculate the flow rate since the flow meter only display the square wave.

From the technical data, it required k-factor to calculate the flow rate and total. The k-factor is the number of pulses generated by the paddle volume of fluid flow. So, how can i acquire the pulse from the digital square wave since i only manage to get the digital square wave? i think my problem is related to programming and calculation.

Perhaps you will understand my problem once you access instruction manual at  http://www.blue-white.com/Products/ElectronicFlow/MicroFlo/MicroFloProduct.asp.(page 9).

[lim25]

I have upload the file also.

http://rapidshare.com/files/303042762/80000-406_microflo.pdf.html

[Baji]

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i face some problem to calculate the flow rate and the total volume of the liquid. Can anyone help me on this matter?

---

What kind of help you are expecting from us.

From the data sheet I extracted the following.

output=6 complete cycle/ Revelution.

60 / K = rate scale factor
rate scale factor x Hz = flow rate in
volume per minute
1 / K = total scale factor
total scale factor x n pulses = total volume

The meter is factory programmed for the correct K-factor of
the body size included with the meter.

so K is unknown? Find K by trial and error method.

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I have succefully read the digital square wave from the sensor.

---

 so apply the above formula to get the total volume. do u have any problem to implent with LabVIEW?, if so then attach your VIs to find the problem in the implementation.

Message Edited by Baji on 11-06-2009 11:15 AM

[lim25]

Yes, i have problem to implement in Labview. Attach herewith the vi http://rapidshare.com/files/303048232/Flow_meter.vi.html. Can you show me how to implement it?

thanks

[sahil]

hiii lim

i think you have got the digital pulses ...

now just use the formula:1 / K = total scale factor
                                       total scale factor x n pulses = total volume

and you will got the total volume...

              60 / K = rate scale factor
rate scale factor x Hz = flow rate in volume per minute

and you will got flow rate...

now please tell where is the actual problem...

[Baji]

as shown above you can calculate the total volume and flow rate. Feed the frquency and total no of pulses as input. Use example finder to know how to measure frequency and no of pulses in the digital signal.