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FFT analysis

Modal analysis

Acoustic analysis

Order analysis

Level Measurements Airborne Sound

FFT analyzer for vibration measurement

Level measurements structure-borne sound

Professional
NVH analysis

Supported Hardware

Flow chart of the software

1. Task measurement
2. Setup-data acquisition
3. Parameters analysis
4. Graphic settings
5. START-Measurement
6. Save measurement

After selecting a measuring task, the modules are automatically called up one after the other. 

The settings must be saved in each module so that these settings are called up the next time the programme is started.

 

 

The supported modules are only visible, if they are activated for the customer.

 

  • When they are purchased by the customer.

 

 

 

A measurement task is selected here.

  • FFT analyzer with 4-channel RogaDAQ4 USB measurement data acquisition.
  • Shown here is the setup and a simple measurement after calibration of three IEPE accelerometers. 
  • With this solution you can handle most vibration problems in mechanical engineering, NVH, “Noise, Vibration, Harshness”, research and development at a fair price.
FRF – Transfer functions
Signal
Triggered Signalblock with
1024, 2048, 4096, 8192, 16384,32768,65536 Samples
FFT-Spectrum
FFT-Spectrum of Signal-Block
FFT T-AVG
Averaged FFT-Spectrum
FRF-Ref Mag + Phase
Transfer function Magnitude + Phase for 1 to 4 References
Coherence
Coherence Function
INV FRF-Ref Mag
Inverse Transfer function Magnitude for 1 to 4 References
FRF-Ref Real-part / Imag-part
Transfer function Real-Part and Imaginary-Part for 1 to 4 References
FRF-Ref Nyquist
Transfer function Nyquist for 1 to 4 References
Magnitude A / Magnitude B
Spectrum Channel A / Spectrum Channel B

Spectral investigations can be carried out in this module. 

This module is suitable for the measurement of transfer functions which can then be evaluated in a modal analysis system.
The transfer functions [m/s²/N] as compliance function and the inverse FRF function [N /m] as stiffness can be displayed simultaneously.

The following tasks can be analyzed in this module:

  • FFT-Analysis
  • Order analysis
  • Acoustic Analysis
  • Level measurements of structure-borne sound
  • Level measurements of air-borne sound
Functions
Signal
Triggered Signalblock with
1024, 2048, 4096, 8192, 16384,32768,65536 Samples
FFT-Spectrum
FFT-Spectrum of Signal-Block
Speed
Speed vs time collected by the counter
Order-Spectrum
Order-Spectrum
Order-Amplitude vs. Speed + Time
Phase of a selected Order vs. Speed + Order vs. Time
Order-Phase vs. Speed + Time
Phase of a selected Order vs. Speed + vs. Time
Order-Polar
Polar Graph Magnitude/Phase of selected Orders
Signal-Ringbuffer
Collected Signal of the Ringbuffer
Angular Resampling Signal
Resampling Signal vs Rotating angle
1X Amplitude vs. Speed
1. Order Amplitude vs. Speed
1X Amplitude vs. Time
1. Order Amplitude vs. Time
1X Phase vs. Speed
1. Order Phase vs. Speed
1X Phase vs. Time
1. Order Phase vs. Time
Time domain Level acc.
Level m/s² vs. Time 125 ms 30 ms 1 s weighted
Time domain Level vel.
Level mm/s vs. Time 125 ms 30 ms 1 s weighted Time domain
Time domain Level disp.
Level μm vs. Time 125 ms 30 ms 1 s weighted
Time domain Speed
Speed vs. Time
Time domain 1X-Ampl. acc.
1. Order m/s² Acceleration Level vs. Time
Time domain 1X-Phase acc..
1. Order m/s² Phase vs. Time
Time domain 1X-Ampl. vel.
1. Order mm/s Velocity Level vs. Time
Time domain 1X-Phase vel.
1. Order mm/s Phase vs. Time
Time domain 1X-Ampl. disp.
1. Order μm Displacement Level vs. Time
Time domain 1X-Phase disp.
1. Order μm Phase vs. Time
Time domain RMS
Root mean square vs. Time
Time domain Mean-value
Mean-value vs. Time
Time domain Peak-Peak
Peak-Peak vs. Time
FFT-Avg.
FFT-Spectrum averaged
Time domain Sound Level
Sound Level Linear vs. Time dB
Time domain Sound Level A-Filter
Sound Level A-Weighted vs. Time dB A
Time domain Sound Level C-Filter
Sound Level C-Weighted vs. Time dB C
Time domain Sound Power dB
Sound-Power vs. Time dB
Time domain Sound Power dB A
Sound-Power vs. Time dB A
Time domain Sound Power dBC
Sound-Power vs. Time dB C
Sound Power FFT
FFT-Spectrum as Sound Power
Sound Power dB vs. Speed
Sound Power dB vs. Speed
Sound Power dBA vs. Speed
Sound Power dBA vs. Speed
Sound pressure dB vs. Speed
Sound Pressure dB vs. Speed
Sound pressure dBA vs. Speed
Sound Pressure dB A vs. Speed
Sound Power dB vs. time
Sound Power dB vs. time
Sound Power dBA vs. time
Sound Power dBA vs. time
Sound pressure dB vs. time
Sound pressure dB vs. time
Sound pressure dBA vs. time
Sound pressure dBA vs. time
1/3 Octave-Spectrum
1/3 Octave-Spectrum Lin / A / C Filter
1/3 Octave-Sound Power
1/3 Octave-Spectrum Sound-Power Lin / A / C Filter
AVG. Sound pressure dB vs. Speed
Sound Level (Average of all Microphones) dB vs. Speed
AVG. Sound pressure dBA vs. Speed
Sound Level (Average of all Microphones) dB A vs. Speed

The following tasks can be analysed in this module:

  • FFT-analysis
  • Order analysis
  • Unbalance calculation
Functions
Signal
Triggered Signalblock with
1024, 2048, 4096, 8192, 16384,32768,65536 Samples
FFT-Spectrum
FFT-Spectrum of Signal-Block
Speed
Speed vs time collected by the counter
Order-Spectrum
Order-Spectrum
Order-Amplitude vs. Speed + Time
Phase of a selected Order vs. Speed + Order vs. Time
Order-Phase vs. Speed + Time
Phase of a selected Order vs. Speed + vs. Time
Order-Polar
Polar Graph Magnitude/Phase of selected Orders
Signal-Ringbuffer
Collected Signal of the Ringbuffer
Angular Resampling Signal
Resampling Signal vs Rotating angle
1X Amplitude vs. RPM
1. Order Amplitude vs. RPM
1X Amplitude vs. Time
1. Order Amplitude vs. Time
1X Phase vs. RPM
1. Order Phase vs. RPM
1X Phase vs. Time
1. Order Phase vs. Time

Modul FFT / Order analysis / Acoustic

After selecting the measurement task, the Data Acquisition window is displayed.

The settings for each measuring channel must be made here. For the speed, 3 signal types can be selected Pulse or periodic signal, Analogue (mV/RPM) or Frequency (mV/Hz). The Execute command accepts the settings and parameterises the hardware. The settings can be managed with Save and Load..

Filter

Filters can be switched on here during data collection. The raw data are therefore filtered.

FFT Analysis Setup

 

FFT-Analysis Block Size and Resolution
FFT waterfall is controlled by a counter.

 

  • Order analysis
    Order resolution and number of orders
    Order waterfall with the counter
  • Speed control
    Run up / run down
  • Level measurements Structure-borne sound
    Total level Acceleration
    Speed Displacement
  • Level measurements Air-borne sound
    A-weighting C-weighting Linear
  • Sound power
    Microphone selection

For sound power, the measurement can be stopped automatically for the stationary case automatisch gestoppt werden.
The data is only active when Execute is displayed.

Example
Sound power with 10 microphones

In the table, the microphone channels must be activated with X. The following quantities must still be taken into account:
The surface, K1 ambient noise and K2 room correction are defined in dB.
With the activation Sound Power Waterfall the measuring points are recorded as a waterfall over speed or time.
For the stationary case there is the option to end the measurement automatically End measurement after.

After running, a new window appears for the channel assignment of the measurement tasks.
The memory space is limited and herewith each channel can take over a task.

Without this selection, no level calculation can be carried out.

Graphics setting

The fonts and colours are defined here.
The zero-degree position can also be defined for the polar display.

Spectrogram

After leaving the scaling and pressing Create, the sonogram appears

Set main graphic

Here, individual diagrams can be displayed one after the other with DISP> and <DISP

Example setup for sound power

Example measurement
Sound power

The following settings are necessary in the analysis setup. If the speed channel is not available, RPM OFF must be set

Fast Slow or Impulse evaluations can be selected for the level calculation.

 

Pressing the Start button starts the measurement.

Calibration of the sensors

With the button Calibration the software changes to the calibration module.

Sensor calibration menu

After calibration, the constants are taken over directly for the next measurement.

 

Structure-borne sound sensors

 

 

and microphones can be calibrated.

 

 

 

Number of averages

 

After selecting a calibration type, the measurement starts with START.

Measurements Loading and Saving

Load Recording

The following data formats are supported:

  • MDF-Format
  • DAT-Format (The data format of the software)
  • MP3-Format (Audio)
  • WAV-Format (Audio)

After the selection, the time course of the recording file is shown in the first diagram.

 

Load: Load new recording file

Setup: Table content of the recording file


Switch on cursor: The analysis area in the time course can be defined with this..

 


Analysis: Setting of the analysis.

 

 

With Start, the analysis begins as with online measurement.

Switch on the cursor: Start click and mark the position in the diagram with the mouse

Exit-Click is for the end position.

Start-Analysis

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