Point-by-point Frequency Measurement

[bpmccain]

I am using an anemometer to measure wind speed. The device puts out an AC signal, calibrated such that 0.75 m / s / Hz.

I have attached my DAQ vi, which is reading 16 different channels simultaneously. It is sampling at 120 Hz (double the 60 Hz maximum rating for the anemometer), and acquiring each sample individually.

This means that I have a stream of data points. I can plot the turbine wind speed easily on a chart (Channel 11), and you can see the AC signal very clearly. However, I don't know how to determine the frequency, since it is a stream of single data points, as opposed to an array of datapoints.

I'm a bit of a Labview beginner, and I have searched for a solution to this for several hours now, so hopefully someone here can give me a hand.

Sorry for the mess of wires; that's what happens when I click the clean-up tool button!

Brian 

[Hueter]

bpmccain

So if you are pulling out one data point, you will need to build this data into an array with an build array VI so you can find the frequency of it. Once you have this data as an array you will be able to use one of several functions that can determine the frequency.

Also as a side note, you do not need to wire the 0-14 constants into the index array VI, normal intervals are the default (unwired) values.

Reply if you still have more questions...

[pine]

You can try the attached code.