Sound and Vibration Assistant - Velocity vs. Frequency graph

[SoundVib]

Hello,

Relatively new to S&V software, I have a PCB Accelerometer connected to a USB 9234 - input signal seems OK.

Couple questions:

- From the "Vibration Level" step setup I selected a single integration (to get velocity) and it shows a graph of Amplitude vs. Time (s), however it does not say what the units of amplitude are (the numbers on amplitude axis have small "u" after them)?

- I can not find a step that allows you to analyze the integrated information in the frequency domain. I am working on measuring a CT medical scanner to show the existing floor vibrations meet the product standards (i.e. 100 micro m/s,rms at 40 Hz ). Currently I can only find a step that allows you to plot Band Power vs. Freq

Thanks

[Finnabon · Accepted solution]

Hi again,

In the Vibration Level Step table, it lists what units the data is in. When you are doing a single integration the units are Voltage*seconds. The numbers with the μ in front of them are equivalent to μV*s. 

All of the analysis tools in SignalExpress for frequency domain are located in Analysis > Frequency-Domain Measurements. The following steps are available: Octave Analysis, Sound Quality, Power Spectrum, Zoom Power Spectrum, Peak Search, Power in Band, Frequency Response, Tone Measurements, Distortion, Tone Extraction, and Noise Measurements. You can select which signal to do the frequency domain calculations on within the step in the Input tab. There you select the signal to be the Integrated signal. 

Allie

[SoundVib]

Thanks, that information helped! I was looking for how to get a Velocity (m/s, rms) vs. Frequency graph, and I finally found it under the "Power Spectrum" step.

One last question!

How do you export the data for the entire measurement instead of just the data at one instance during the measurement?

Here's what I am doing:

-Lets say I have an Acceleration input with a Vibration Level step

-Under the "Vibration Level" step in the column on the left, I right-click on Acceleration and export the data to a text file

-This only gives the acceleration values for one second of the measurement (I need the values for the entire measurement duration)

[SoundVib]

Thanks for all your help, I actually answered my own question by adding a "save data" step to the measurement!