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Sound and Vibration Instrument Hire and Calibration

Norsonic 840 Specifications


Norsonic 840 Real time Analyser
 

The Nor 840 has been withdrawn, the following information is for reference purposes only.

 
Nor 840   Real Time Multi-spectrum Analyser, Sound Intensity System  
 
Analogue Inputs : dual channel analyser
Microphone inputs (2) : 7-pin LEMO connectors are standard
preamplifier voltage : 120 V, 3 mA to each preamplifier
polarisation voltage : 0, 28 or 200 V selectable, ± 1%
Direct inputs (2) : BNC connectors
Charge inputs (2) : TNC connectors
Intensity Input : 18-pin LEMO connector
Maximum input signals : 120 V PEAK, Line and Mic. inputs
Input impedance : 1 MΩ / 120pF, all inputs
 

Input Amplifiers :


Amplifier gain : -40 dB to +70 dB in 5 dB steps
additional gain : 0 to 10 dB with accuracy and resolution < 0.1 dB for calibration purposes
Measurement range : 0.03 µV - 31.6 Vrms.
corresponds to SPL values from -20 dB to +150 dB with a microphone sensitivity of 50 mV/Pa
Amplification error : Better than 0.2 dB : 20 Hz - 12.5 kHz
 

Frequency range - AC output :


0.1 Hz to 100 kHz with ± 0.5 dB
0.05 Hz to 200 kHz with ± 3 dB
High-Pass filters : 3-pole Butterworth selectable at 0.63 Hz or 20 Hz, all inputs
Low-Pass filter : 3-pole Butterworth selectable at 2 kHz, charge inputs only
Hum and Noise :
Mic. Input : 10 dBA : 15 dB Lin
Line input : 0 dBA : 3 dB Lin, measured with a preamplifier and dummy microphone
 

Analogue Outputs :


Wideband outputs - 2 : BNC connectors. The output signal comes directly from the input amplifiers
Output impedance : Max. 10 Ω
Output level : ± 10 V peak, 3.16 V RMS corresponds to full scale on display. Outputs are short circuit proof to ground and output current are in excess of 10 mA
 

Analogue to Digital Converter :


Converter type :   16 bits linear
Sampling rate :   64 kHz, 15.625 µs
 

Filters and Networks :


Anti-aliasing filter :

10-pole Chebychev low-pass filters
Frequency range : DC to 27.6 kHz
Passband ripple : < 0.1 dB
Stopband attenuation : > 75 dB above 1.3 × cut-off frequency
Phase matching : < 0.1 ° for 10 Hz - 5 kHz., <1.0 ° for 0.1 Hz - 10 kHz
 

Digital filters :

6-pole llR filters for 1/1- and 1/3-octave bands. The 1/3-octave centre frequencies are set with the factor 10n/3
Frequency range : 0.125 Hz to 16 kHz for 1/1-octave bands or 0.1 Hz to 20 kHz for 1/3-octave bands
Filter response : The 1/1 and 1/3-octave filters meet the requirements from IEC 61260 class 1
Weighting networks : The true A and Lin-networks fulfil the requirements to BS EN 60651 Type 0 for precision sound level meters
Lin network : 25 Hz to 16 kHz, - 0.3 dB and 17.8 Hz to 22.3 kHz, - 3.0 dB
Calculated networks : A, B, C and Lin-networks as well as up to 4 user defined networks may be calculated as a sum of the frequency band within the set frequency limitations.
 

Level Detector :


Detector Type : Digital true RMS
Resolution : 0.1 dB in accordance with BS EN 60651 and BS EN 60804 Type 0
Linearity Range : 75 dB, BS EN 60804 type 0
Pulse range : 78 dB, BS EN 60804 type 0
Accuracy : 20 Hz to 12.5 kHz
+5 dB above to 60 dB below FS : < 0.2 dB
60 dB to 70 dB below FS : < 0.4 dB
70 dB to 80 dB below FS : < 1.0 dB
Time constants : Selectable in a binary sequence from 1/16 s to 8 s. plus Impulse.
The 1/8 s (Fast), the 1 s (Slow) and the Impulse are in accordance with BS EN 60651 Type 1
Integration period : 4 ms to 100 hours with 1 ms resolution.
Crest factor capability : 10 dB crest factor margin at FS increasing to 90 dB at 80 dB below FS
 

Display :


Display type : 10.4” bright, back-lit, TFT, VGA colour LCD screen.
Picture resolution : 640 (horizontal) × 480 (vertical) pixels - VGA standard
Display formats : one or two windows, with or without added information. Each window may individually present data from selectable channel and selectable parameter(s), as a numeric table, as a level vs. frequency graph, or as a level vs. time graph.
Displayed range : selectable to 20 : 40 : or 80 dB
Graphical resolution : 0.1 dB to 0.8 dB depending on selected format
Numerical resolution : 0.1 dB
Numerical range : -99.9 dB to +199.9 dB
 

Measurement Storage :


Internal storage : up 32.000 full frequency single channel spectra.
Actual usable number will vary, based on used channels, used registers, used parameters and used frequency range.
Floppy-disk : 1.44 Mbyte 3-1/2” floppy-drive DOS compatible format gives approximately 250 single mode measurements
or 100 multi-spectrum measurements each having 1000 periods.
Hard-disk : Minimum 2.1 Gbyte hard disk MS-DOS compatible format gives approx. 262,500 single mode measurements
or 105,000 multi-spectra measurements each having 1000 periods.
 

Digital Interfaces :


Control : Almost any setting or any data readout may be done using the digital interfaces
IEEE-488 :Meets the IEEE Standard 488-1978.
RS-232C : Meets the RS-232C Standard for normal serial interfaces with handshakes.
Printer : Graphic screen-dumps or numeric tables may be printed out using the Centronics parallel interface.
 

Signal Generator :


Output : BNC connector
Output impedance : <10 ohm, ±10 mA
Signal types : Random or Pseudo-Random noise.
Spectra : White, Pink, 1/1-octave or 1/3-octave noise.
Repetition rate : approx. 28 minutes corresponding to 0.00006 Hz spectral line separation
Filters : the 1/1- and 1/3-octave filters meets the requirements from IEC 61260 class 1
Output level : selectable in 1 dB steps in the range 0 to 60 dB relative to 1 Vrms
 

General :


Power requirements : 30 W : 11-15 VDC.
Dimensions : 34 × 21 × 35 cm (W×H×D) without battery case
Weight : 9.7 kg without battery (12.3 kg with Battery Case type 330A)
 

Overall Performance :


The overall performance of the Nor-840 with a suitable microphone and preamplifier, such as the Norsonic 1220 and 1201, corresponds to the Sound Meter Level Standards BS EN 60651 Type 1, BS EN 60804 Type 1
The filter characteristics are designed after the most stringent criteria of the Filter Standard IEC 61260 class 1 for analogue and digital filters as well as the ANSI S 1.11 - 1986 Type 1D. The filter also meets the older IEC 225 Filter Standard.
 
E&OE - specifications subject to change without notice.