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Searching for maximum FFT values

I have lots of vibration data that was recorded in multiple length time segments.  For example, one group may contain 5 seconds of data, and the next group may contain 30 seconds.  Each group contains 15 channels of accelerometer data (5 sensors with 3 axis/sensor). 

 

What I would like to do is pragmatically scan through the data streams and capture the highest amplitude accelerations that occur in a given 1 second interval within a specified window of frequencies. 

 

The data was collected at a sample rate of 1kHz resulting in FFTs that go up to 500Hz.  However, I am actually only interested in frequencies between 1Hz and 50Hz. 

 

Is there a way that this could be done?

 

Thanks,

 

Doane

 

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Hi DBuskar,

 

If I get you right, you should filter the original channels - either with digital low pass (0 – 50 Hz) or a band pass filter (1 – 50 Hz). Then calculate the start and stop row for your 1 second interval and calculate the max amplitude with the statistic function. Repeating these 15 times for all channels it makes sense to create a script for these steps.

 

Greetings

Walter

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Hello Walter, and thanks for the reply.

 

I would need to calculate the max amplitude within the 1-50 Hz range first in order to determine where my desired 1 second interval is. 

 

I agree that a script is in order.  I have started doing this manually, but doing so is taking me a very long time.

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Hi DBuskar,

 

Please find attached an example for your request.
I hope this shows what you are looking for.

Greetings

Walter

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