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Sound and Vibration Instrument Hire and Calibration

Bruel & Kjaer 2260E : BZ 7205 Specifications


Bruel & Kjaer Sound Intensity Analyser
 
B&K 2260E   Sound Intensity Meter £ 42 a day *
 

B&K 2260 with BZ 7205 - Sound Intensity Software


Specifications are given for Type 2260 with software BZ 7205 installed and fitted with Sound Intensity Probe Type B&K 3595 consisting of 1/2" Microphone Pair Type 4181 or Type 4197 and Dual Preamplifier Type 2683
 
Unless otherwise noted, values are given under reference ambient conditions with nominal sensitivities for the microphones and preamplifiers (see Product Data sheet for Type 3595) and with a 12 mm spacer
 

Reference Conditions


Reference Sound Pressure Level: 94 dB
Reference Frequency: 250 Hz
Reference Temperature: +20 ° C
Reference Static Pressure: 1013.25 hPa
Reference Relative Humidity: 65%
 

Instrumentation Standards


Conforms with the following standards:
 

Measurement and Calculation Standards


Measurement and calculations can be made according to the following standards:
 

Frequency Range


Octave and 1/3-Octave spectral measurements based on a linear electrical frequency response
For Intensity Measurements: 9.3 Hz - 21.6 kHz (-3 dB points)
For Dual-channel Measurements: 5.2 Hz - 21.6 kHz (-3dB points)
 

Octave Band Centre Frequencies

: 31.5 Hz to 8 kHz
 

1/3-octave Band Centre Frequencies

: 25 Hz to 10 kHz
 

Frequency Weighting


Lin and A-weighted total results are based on weighted summation of spectral bands in the frequency range 22 Hz - 11.3 kHz. Frequency bands can be manually excluded from calculation.
 

Pressure-residual Intensity Index


The minimum Pressure-residual Intensity Index (the 'Processor' in IEC 61043), measured with pink noise at a band-filtered level of 114 dB in the 143 dB Full scale range is given below
 

Minimum Pressure-residual Intensity Index for the Analyser


Residual Sound Intensity example

Enhanced Phase Matching


The phase match of the sound intensity system can be enhanced in the frequency range 31.5 Hz - 500 Hz using a Sound Intensity Calibrator Type 3451. This can increase the Pressure residual intensity index for the sound intensity system up to 10 dB, depending on frequency.
 

High Frequency Compensation


Selectable high frequency compensation for the 1/2" microphone and 12 mm spacer combination. The Mean pressure and the Sound intensity spectrum can then be measured at frequencies up to 10 kHz (one octave higher than the normal theoretical limit).
 

Detectors

Linear integration: 1 s to 59 min. 59 s in 1 s steps
 

Resolution

Discrete Parameters: 0.1 dB
 

Overload Indication


Latching overload indicators are displayed on all measuring screens. An overload percentage is measured and attached to all measurements.
 

Auto range


Manual and automatic range control are provided
 

Spacer Settings


Spacer Length: 6 - 200 mm in 0.5 mm steps
 

Measuring Range


Mean Pressure: Full Scale is the maximum level of a sinusoidal input signal (Crest Factor 1.4) that does not give overload.
 
Upper Limit is the maximum pressure level for each band that does not give overload with a pink noise input signal. Pink noise has a Crest Factor of 4 and is band-limited from 20 Hz to 20 kHz
 
Lower Limit is the input level that gives the stated error in the measured value for the worst-case filter band. For other filter bands the limit will be lower 7 ranges giving:
 

Octave Bands


Full Scale Upper Limit Pink NoiseLower Limit Error +0.3 dBLower Limit Error +1 dBLower Limit Error +3 dB
143 dB121 dB< 29.7 dB< 24.1 dB< 18.2 dB
 

1/3-octave Bands


Full Scale Upper Limit Pink NoiseLower Limit Error +0.3 dBLower Limit Error +1 dBLower Limit Error +3 dB
143 dB116 dB< 25.0 dB< 19.4 dB< 13.5 dB
 
Individual channel pressure: When the 2260 is used as a dual-channel analyser the inherent noise in each channel is 3 dB higher than when measuring Mean pressure. Therefore, add 3 dB to the Lower limit figures stated for Mean pressure to get the Lower limit for individual channels.
 

Ambient Conditions Settings


Temperature
Static Pressure
 

Calibration


External (acoustic): Individual (Pressure) gain calibration of the two input channels can be performed using Sound Intensity Calibrator Type 3541, Sound Intensity Calibrator Type 4297, Sound Level Calibrator Type 4231 with Coupler DP 0888 or an unknown calibrator.
 
A Preamplifier gain can be set.
Internal: Using internally generated electrical signal combined with keyed-in value of the microphone's open circuit sensitivity.
 
A Preamplifier gain can be set.
Phase Calibration: The phase difference between the two channels in the frequency range 31.5-500 Hz can be calibrated to a minimum using Sound Intensity Calibrator Type 3541
 

Verification

Verification of the Pressure-residual intensity index can be made using Sound Intensity Calibrator Type 3541. Pressure-residual intensity index is stored with the calibration and in the measurement job for documentation purposes.
 
Measurements are automatically compensated for keyed-in changes in temperature and ambient pressure.
 

Field Check

A field check of the intensity measured with the probe in normal and reversed position can be performed.
 

Internal Generator


Pseudo-random white noise generator
 

Modes


The four main modes are:
System: Used to install software, change application, set the internal clock, copy files, etc.
Set-up: Used to set up measurement and control parameters Calibrate: Used when calibrating the analyser
Measurement: Used to view current and recalled measurements
 

Measurements


For Sound Power and Sound Reduction Applications: Simultaneous measurement of Mean pressure and Intensity
 
For General Dual-channel Applications: Choose between simultaneous measurement of: Mean pressure and Intensity, Mean pressure and Reactive intensity, Mean pressure and Particle velocity, Particle velocity and Intensity, pressure Ch. 1 and Real part of cross spectrum, or Pressure Ch. 1 and Pressure Ch. 2
 

Measurement Control


Manual or semi-automatic. Measurements are started manually and the user is guided through the different scanning for each segment (according to the selected standard). After storing the scans for one segment, the analyser is automatically ready to make measurements for the next segment. 16 different measurement sequences are available.
 

Pause/Continue


A measurement can be paused or continued
 

Pause/Back Erase

It is possible to erase backwards to the last pause or to the start of the last scan
 

Surface Definition


 

Calculations


Calculations of sound power can be done on each segment or surface in conformance with BS EN ISO 9614-2, ECMA-160 and ANSI S12.12 standards, or for non-standard measurements.
 
Calculations of corrected intensity sound reduction index (RI,c or RI45°,c) and weighted corrected intensity sound reduction index (RI,cw or RI45°,cw) can be done on each segment or surface in conformance with ISO/DIS 15186-1 and BS ISO 717-1.
 
Frequency bands, segments or surfaces can be manually included in or excluded from calculations.
 
The following status information is available for each frequency band, segment or surface: Data excluded, Dynamic capability failed, Repeatability failed, Convergence Index failed, Extraneous noise too high, Scan time too short, Area not defined, Missing data in segment, Overload, Copied data, A-weighted total level contains high levels in bands outside standard-defined frequency range.
 

Displays


Spectrum: For display of one of the two measured spectra, both spectra simultaneously, power, PI index with dynamic capability, repeatability with the allowed limit, convergence index with the allowed limit, extraneous noise with the allowed limit, the difference between the two measured spectra, or the corrected intensity sound reduction index (RI,c or RI45°,c,).
 
Status codes are shown below each frequency band.
 
The A-weighted or Linear spectrum can be displayed together with A-weighted and Linear total bands.
 
The Y-axis can be zoomed to 5, 10, 20, 40, 60, 80 or 100 dB.
 
Surface: For display of number map or contour map with 4 x 4 or 8 x 8 segmentation with results from the segments or surfaces within a surface.
 
It is possible to display the values from a selectable frequency band together with status information.
 
It is also possible to display the following quantities (together with status information): one of the total values from one of the two measured spectra, power, PI index, repeatability, convergence index, extraneous noise, the difference between the two measured spectra or (weighted) corrected intensity sound reduction index.
 
Maxima are annotated on contour map displays.
 
Compass: For display of the direction of the sound field near the probe.
 
All displays have cursor read-out capability.
 

GPS Data


A position can be attached to a measurement job by inputting data from a GPS (Global Positioning System) receiver via the serial interface. Receiver Standards Supported: NMEA 0183 ver. 2.20, optional corrected to Differential GPS using RTCM104 ver. 2.1
Baud Rate: 4800
 

Storage System


Internal: Up to 32 Mbyte disk for application software and storage of set-ups and measurement data within jobs. Jobs can be recalled for calculation and display, continuation of measurements or re-use of set-ups
Capacity: 5, 10, 20 or 32 Mbyte. The supplied application software requires approximately 1.6 Mbyte. A 1/3-octave job containing 100 segments requires approximately 40 Kbytes
External Memory Card: For storage/recall of measurement data and transfer of data to and from a PC. Available as 5, 10, 20 or 32 Mbyte ATA flash cards of SanDisk type
MS-DOS®: Compatible file system (from ver. 3.3)
 

Serial Printer/Output


Set-ups and measurement data can be printed on a Portable Printer Type 2322 or on an IBM Proprinter (or compatible). It is possible to print screen dumps or tables.
Measurement data can also be output in spread sheet format for post-processing on a PC.
Baud Rate: 1200 to 38 400
 

Remote/Local


Commands for transfer of measurement data (files) in binary form to a PC for use with Bruel & Kjaer application software.
Commands for start and stop of measurement and transfer of current measurement in ASCII form to a PC.
Baud Rate: 1200 to 115 200
 

Input Stage Connection :

10-pin LEMO
 

Auxiliary Outputs


AUX. 1: Can be set to either the Internal Generator (White Noise) or an internal signal from the digital signal processor. That is, Channel 1, Channel 2, Sum of Channel 1 and 2, Difference between Channel 1 and 2 or Integrated Difference between Channel 1 and 2
 
AUX. 2: Can be set to output the input signal, the aural feedback signal, a combination of the input signal and the aural feedback or an internal signal from the digital signal processor. Available signals from the digital signal processor: Channel 1, Channel 2, Sum of Channel 1 and 2, Difference between Channel 1 and 2 or Integrated Difference between Channel 1 and 2
 
Gain for AUX. 1 and 2: Can be set separately from 0 to -80 dB in 1 dB steps
 

AC Inputs/Outputs


AC Output: Buffered, unweighted microphone signal
AC Input: Alternative to microphone preamplifier input
 

Settling Time

From power on: 1 minute
 

Miscellaneous


Help Concise context-sensitive help for keys and menus
Languages All software is available in English, German, French, Spanish or Czech
Clock Back-up battery powered clock. Accuracy better than 1 minute per month
Display Hardware Transflective back-lit LCD 192 x 128 dot matrix with internal temperature compensation
 

External DC Power Supply


Voltage: Regulated or smoothed 10 to 14 V, max. ripple 100 mV
Power: 3.5 W
Current: 300 mA
Inrush Current: 1000 mA
Socket: 5.5 mm diameter, 2 mm pin (positive)
 

Batteries


Type: 6 x Lr14/C-size 1.5V alkaline,
Lifetime: (at 20 °C) 5 to 6 hours of typical use (decreases significantly at low temperatures)
 

Weight

1.1 kg including batteries, excluding probe
 

Dimensions

290 x 120 x 52 mm without probe
 
E&OE - specifications subject to change without notice.