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Sound Power Measurement with Hemispherical Array

Sound power measurement with MF710 / MF720. They are hemispherical arrays developed by BSWA for sound power measurement.

MF710 meets the requirements of the 10-microphone method according to GB 6882 1986, ISO 3745:1977, GB/T 18313 2001 and ISO 7779:2010.

MF720 meets the requirements of the 20-microphone method according to GB/T 6882-2008 and ISO 3745:2012.

The MF710 / MF720 was developed as a small, lightweight and easy-to-mount bracket.

Microphones can be mounted on the hemispherical surface very quickly and accurately, making it very easy to comply with the standard requirements for sound power measurement.

Description:

 

Meets the requirements of GB/T 6882, ISO 3745, GB/T 18313, ISO 7779

The mic can be moved along the rail to meet 10 and 20 mic method

Different types of microphones with 1/2 inch preamp can be mounted

It can be fixed to the floor or hung

Easy to take on, light and compact, supplied with a professional carrying case

Suitable for sound power measurement in the laboratory and outdoors

Sound Power Measurement Kit 

MF710 Package Offer

IEPE Interface
Model
Description
Qty
Price
MF710

Microphone holder for sound power measurement Radius 1m

1
3250 €
MP30

1/2″ IEPE measurement microphone
class 1 WS2F 10 Hz to 20 kHz Intrinsic noise 16 dBA

10
7750 €
CA111

Sound calibrator; conforms to IEC 60942 Class 1
for 1/2″ and 1/4″ microphone capsules with
quartz-controlled oscillator for checking
the accuracy of IEC 60942 Class 1 sound level meters.
94 dB and 114 dB @ 1000 Hz output level selectable

1
840 €
RogaBNC5

5 meter, BNC-BNC cable with bend protection
RG174A/U coaxial 50Ω, 295 Ω/km, shielded, black

10
620 €
10-XLR-NVH

10 channel IEPE measurement microphone
data acquisition system
Behringer X Air XR18
24 bit 10 Hz to 20 kHz per channel
NVH Analyzer Pro

1
6050 €
Freight Costs
DAP
200 €

Total Price

EUR
18670 €

NVH Analysis – NVH Analyzer Pro – Function Overview

REALTIME DATA PROCESSING
GRAPHICS AND VISUALISATION
User interface
Configurable graph screens
Time domain
Recorder (1 to 16 Ch, real-time autoscaling)
Scope (trigger, persistence, envelope), Analog/digital meter, tabular display, overload indicator
Multi domain
XY recorder (Lissajous), 2D graph, Orbit graph
FRF plot (amplitude/phase/real/imaginary vs frequency)
Application specific
FRF geometry, Modal circle, Rotor balancer, Harmonic FFT, Vector scope
Auto-generating of displays with typical application setup
DATA IMPORT
ASCII *.txt
WAV *.wav
MP3 *.mp3
Stiegele Datasystems MicroEdition, *.mdf
TEAC TAFFmat Format, *.hdr, *.dat
DATA EXPORT
ASCII *.txt
Excel *.csv
FILTERING
IIR
Low pass/high pass/band pass/ 2nd to 6th order, Butterworth
STATISTICS
Calculation base
Time based
Types
RMS, Average, Peak-Peak
Data range
Running, Triggered, Start-Stop
REFERENCE CURVES
Types
time, value, dual-value, vector, XY, frequency domain with interpolation
TIME DOMAIN
ANALYSIS
Integration/Derivation
single/double with adjustable filter, automatic unit conversion
(e.g. acceleration to velocity to displacement) FFT
FFT ANALYSER
General
multiple independent FFT analyzers at the same time
Amplitude types
amplitude FFT (Ampl, RMS, Power, PSD, RMS SD), Complex FFT (Real/Imag/Ampl/Phase)
Windowing
Hanning / Hamming
Window overlap
0, 10, 25, 50, 66, 75, 90 %
Triggered FFT
triggered time-range with pre- and post-trigger as input, auto calculation of window resolution, averaging of triggered FFT‘s, e.g. for bump – impulse hammer test application
DC cut off
0,5 Hz
FFT block size
26, 51, 101, 201, 401, 801, 1601, 3201, 6401, 12801, 25601
Acoustic weighting
A, B, C, Lin (Z)
Octave
1/3, type; Lin/A/B/C weighting, Lin/Pk avg with overlap
Visualization
amplitude axis with real-time autoscaling: Lin/log/0dB/reference dB/Sound(A)
Post processing
possible to add/change all calculations offline on the stored raw data
Spectrum markers
Free
ORDER TRACKING

Frequency source

Counter: optical tacho, proximity, pick-up probe (1 pulse/rev), optical strip tape probe
(with bl/wh tape, algorithm for determining number of pulses),
1-, 2-, 3- tracks encoder, gear tooth with missing teeth (e.g. 60-2), CDM, CDM with zero
RPM channel: any analog speed channel, virtual (synthesized RPM channel, also in post-processing) Analog pulses: analog signal (e.g. 60-2) / analog tacho + angle sensor math
Input Ch. for analysis
any analog input channel, e.g. IEPE accelerometer, microphone, etc…
Visualization
3D graph, Order and Frequency spectrum, Waterfall FFT real time extraction of single spectral lines of matrix Orbit plot, XY recorder, Bode plot, Nyquist plot of any order, any signal vs RPM
Calculation criteria
Runup / Coast down / Both directions with RPM limits and Delta RPM and/or Delta Time
Order FFT
from 8 to 256 orders, resolution from 1 to 1/64
Harmonics
extract overall RMS and amplitudes/phases/Real/Imag of selectable orders (from sub-orders e.g. 0.1x, 1x, 2x, 3x to max order) in Time domain & RPM domain
Post processing
possible to add/change all calculations offline on the stored raw data
Data export
Complex data (Real/Imag/Ampl/Phase) in any format, see Software Export section
TORSIONAL VIBRATION
General
high precision rotational and torsional vibration and slippage measurement, by use of 2 rotary encoders
Frequency source
optical strip tape probe (with bl/wh tape, algorithm for determining number of pulses), 1-, 2-, 3- tracks encoder, gear tooth with missing teeth (e.g. 60-2), CDM, CDM with zero
Angle accuracy
up to 0,00075° at 10 000 rpm
Angle resolution
up to 0,06° at 10 000 rpm
Features
Rotational DC filter (0,1 to 10 Hz), compensation of uncentered encoder mounting
Output
Rotational angle/velocity, Torsional angle/velocity
Visualization
angle based view, time domain
MODAL TEST
Impact hammer method
roving hammer/roving accelerometer moving through points, averaging of multiple hits, double hit rejection, rejecting of hits (action buttons), grouping of sensors, adjustable excitation, and response window
Free-run mode
Function generator (Apollo Series) for shaker excitation (swept sine, burst, chirp…) Hanning/Hamming windowing with overlap 0, 25, 50, 66, 75 % operating deflection shapes (Spectral ODS)
FRF
Receptance, Effective Mass, Mobility, Impedance, Dynamic Compliance, Dynamic Stiffness, Transmissibility
Modal Parameters
Mode Indicator Function (MIF), extract exact frequencies and damping factors with Modal circle fit (Option)
Post processing
FRF from stored raw data, in free-run mode
Geometry
Geometry editor, load, save, import models in UFF (UNV) format (Option)
Animation
movement of nodes for selected frequency (place marker), change speed and amplitude (Option)
Data export
Complex data (Real/Imag/Ampl/Phase) in UFF (UNV) format or any other, see Software Export section
HUMAN BODY VIBRATION
General
module for judging vibration levels for risk of damage to the human body
Supported types
Hand arm
Compliance
to ISO 8041, ISO 2631-1, ISO 2631-5, ISO 5349 standards
SOUND LEVEL
Frequency weighting
A, B, C, Lin (Z)
Time weighting
Fast, Slow, Impulse
Octave plot
1/3 Lin/A/B/C/ weighting, Lin/Pk avg with overlap
Supported standards
IEC 60651, IEC 60804, IEC 61672
Outputs
Sound pressure level, any combination of Frequency and Time weighting, Leq, Lpk, Lim, LE overall or on custom statistical rate, percentile levels (1, 5, 10, 50, 90, 95, 99 %)
More features
real-time narrow band FFT, frequency weighted raw channel
Calibration
auto-calibration of scaling factor with reference calibrator (1kHz, 94dB, 114 dB acc to IEC 60942:2003)
BALANCING
Application
for rigid rotor running below its resonance frequency, based on order tracking (amplitude & phase), single- and dual-plane
Supported tacho inputs
Counter: optical tacho, proximity, pick-up probe (1 pulse/rev), optical strip tape probe (with bl/wh tape, algorithm for determining number of pulses), 1-, 2-, 3- tracks encoder, gear tooth with missing teeth (e.g. 60-2), CDM, CDM with zero RPM channel: any analog speed channel, virtual (synthesized RPM channel, also in post-processing) Analog pulses: analog signal (e.g. 60-2) / analog tacho + angle sensor math alarm output if velocity exceeds predefined value weight splitting
Visualization
Vector polar plots of 1st order of all runs
Sequence
step-by-step guidance through procedure: initial run, trial mass run, correction mass run, repeat steps if needed
Features
x and y direction balancing at the same time, when using triaxial sensor
SOUNDPOWER
Standards
ISO 3741 (noise source in reverberation test room), ISO 3744 (engineering grade, free field over reflective plane), ISO 3745 (precision grade, anechoic or hemi anechoic room)
Geometries
Parallelepiped, Cylindric, Hemisphere, Sphere
Microphones
10 number of microphones; positions will be calculated according to entered geometry and size, floor / 1 wall / 2 wall setup
Measurement
Guided sequence, previous/next group (action buttons), background noise/sound measurement, with repeatability check, minimum measurement duration & level plausibility check and warnings, grouping of microphones
Octave
1/3 octave
Correction methods
C1 and C2 meteorological, K1 background noise and, K2 room noise (mean absorption grade, reverberation time, K2 editor)