1.2 Serial Frequency Analysis - Advanced Test Equipment Rentals
Contents
1. Tritter S Tpwei Optimized s T Freq Coat 0 25 dB 0 5dB 1 0dB Hz 1 3 1 4 S 2 oct oct 1 3 1 4 1 3 1 4 1 3 14 oct oct oct oct oct oct 160 0 5 8 24 2 06 0 52 125 0 5 0 7 10 37 3 42 2 59 0 86 0 65 0 25 100 0 5 13 06 3 27 0 82 Fast 0 475 80 0 5 Slow 3 8 16 44 4 11 1 03 62 5 0 63 0 7 20 70 6 79 5 18 1 70 1 29 0 42 50 0 8 26 06 6 52 1 63 40 1 0 7 32 81 13 58 8 20 3 39 2 05 0 85 Table 1 1 cont Settling and dwel times used for calculating the total measurement time 2238 Mediator Frequency Analysis Software BZ7123 User Manual Bruel amp Kj r Chapter 1 Introduction Measurement Parameters 13 Measurement Parameters 13 1 Spectrum Parameters Table1 2 lists the spectrum 1 1 or 1 3 octave band parame ters available with the Frequency Analysis module The Y suffix in the parameter names refers to time weightings F or S Spectrum Parameters Default Freq Time Parameter Screen Definition Weight Weight Parameter ing ing Leg LikHzeq Equivalent continuous E level for the current fre quency band Lymax LikHzFMax Max Lyp value detected F or S within the current fre quency band Ly Min LikHzFMin Min Lyp value detected F or S within the current fre quency band Table 1 2 Spectrum parameters available with the Frequency Analysis module 13 2 Broadband Param2. Selecting Spectrum Parameter for Display During measurement or when a measurement is finished you can change the displayed spectrum parameter in the Working and Averaged Spectrum Windows You can select the follow ing spectrum parameters Lxey Lxymin Or Lymax M zcan Ho Fig 4 2 The Spectrum Parameter field highlighted 1 Usethe A or W keys to select the Spectrum Param eter field 2 Usethe 4 p keys to select the spectrum parameter The display changes accordingly 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Measurement Result Windows 4 14 Using the Spectrum Cursor When a measurement is finished you can use the 4 keys to step the cursor through the measured frequency bands in the Working and Averaged Spectrum Windows The frequency and associated measurement value can be seen in the parameter line 4 15 Overloads Instantaneous and latched overloads are displayed in the Broadband M easurement Window in the same way as in the Measurement Window in the Basic module In the Working and Averaged Spectrum Windows the over load indications are shown to the right of the spectrum dis play The latched overload indicates that an overload occurred in one or more of the frequency bands during measurement In the Averaged Spectrum Window the latched overload may have occurred in any of the scans if a number of scans were selected Note Ove
3. 8 8 Auto Start 1 4 query 8 8 Aux 1 query 8 8 T Aux 2 command 8 5 Aux 2 query 8 8 T au PORE t KE li Moe iced E Bandwidth command 8 5 4 parame er line Bandwidth query sss 8 8 weighting H Broadband Weighting command 8 5 Tolerance errer 1 6 Broadband Weighting query 8 8 T otal remaining meas time 1 6 4 3 command 5 voie se 8 5 Trigger Dwell_Time command 8 5 Dwell Time query eene 8 8 Limits command eene 8 6 Limits query 8 8 No Of Scans command 8 6 U No Of Scans query eee 8 8 Underrange ereer rere errer rrr Random Frontal command 8 6 Underage un erre REP Random Frontal query 8 8 Up Down Arrow key Ni Recall command 8 6 Using the spectrum cursor eee 4 5 SAVE command eee 8 6 SE quence command sees 8 7 SEquence query 8 8 W TI me command 8 7 Weightings Window emm 3 2 TIME QUERY sies t rrr mper 8 8 Working Time Weighting command 8 7 E Eg query vas Sap eene 8 9 Time Weighting query 8 8 LMAX query 8 9 TOlerance command 8 7 LMIn query 8 9 Wie UEN aus SETS ER Spectrum Window 1 6 4 2 Wind Screen query emmessssnrvsrrserssersssnrsnnns 8 8 Working QUOC ise etitm eran S Set up data 5 2 X key 2527 SU een de 1 9 SEtup query 8 7 Single scan storing 5 4 Socket reference to ee 1 3 Y SOE K
4. Appendix 2 Interface Explains the programming of the interface jobs for the Frequency Analysis module mmgmgmImmm BB1128 11 2238 Mediator 0 Frequency Analysis Software BZ 7123 User Manual I UJ I ndex 0 4 2238 Mediator Briel amp Kj r Frequency Analysis Software BZ7123 User Manual Chapter 1 Introduction 1 1 About this Manual 1 2 Summary of Contents 1 2 About this Volume eee nnns 1 3 Detectors teen eco eese cre rupe ex bu rre Eee cds 1 4 Stati Sti ETT TE 1 5 Se TT 1 5 Measurement SeOUuUenCGS esse eee eee eree eee 1 5 AUX T 1 5 VNE D GO AEEA E EPA APAE endet esd d en a rc exa wa 1 5 Measurement Set up Menu sees eee eree eee eee 1 6 1 2 ChangingApplication sse 1 6 1 3 Measurement Parameters ccc 1 6 BB1128 11 2238 Mediator 1 1 Frequency Analysis Software BZ7123 User Manual Chapter 1 Introduction About this Manual 1 1 1 1 1 About this Manual Summary of Contents Chapter 1 Introduction provides a general overview of the Frequency Analysis module its functions and in formation about serial frequency analysis Chapter 2 Key Functions provides information about the key functions for the Frequency Analysis module Chapter 3 Measurements Set up Menu gives in structions for setting up the measurement parameters for the Frequency Analysis module Chapter 4 Measuring gives information about using the Broadband Measure
5. Example reading the working Leq value Query from controller Working LEq From Mediator values in dB WORKING LEQ 48 8 45 9 51 6 52 0 BB1128 11 2238 Mediator 8 9 Frequency Analysis Software BZ 7123 User Manual 2238 Mediator Frequency Analysis Software BZ7123 User Manual Br el amp Kj r Chapter 9 I ndex Numerics Backlight 2 4 1 1 octave and 1 3 octave key 2 4 band filters 623 Bandwidth setting issuer 3 3 3 2 Batteries SAVING sse 2 4 3 3 Broadband dater edd oe teneo deas 2 measurement 4 A measurement results 5 2 5 3 AC output 6 2 Measurement Window 1 6 1 9 4 2 4 4 Application programs eee 2 2 parameters nccrne 1 9 Auto SaVe cca esee itte teni 3 5 Start icon 4 7 6 2 Automatically saved files s es 5 3 Calibrate Key sse 2 2 AUX Tete 3 6 Calibration AC Output 3 6 SEt UP HHHH 5 2 Output 6 2 time 5 2 AUX 2 sss 6 2 Cancel key 2 4 DC Output 3 6 Centre frequency sse 1 5 Output 6 2 Command Trigger INPE ioter meme 3 6 message Overview sese eee eee eee ee 8 2 Trigger Output sees 3 6 SEtup 8 5 Average Auto Save 8 5 EQ query vi 8 3 AUX 2 8 5 LMAx query 8 3 Bandwidth 8 5 LMIn query 8 3 Broadband Weighting 8 5 Average query 8 2 Dwell Time 8 5 Averaged Spectrum Window A 5 4 Limits 8 6
6. sss 8 2 Awveragge iei tede et netvibes 8 2 PArameter itte n nri terreri 8 3 SEUD hsr 8 5 Working ss orto etre E ER bien 8 9 BB1128 11 2238 Mediator 8 1 Frequency Analysis Software BZ 7123 User Manual Chapter 8 Interface Controlling Mediator via the Serial Interface 8 1 Controlling Mediator via the Serial Interface 8 1 1 Commands and Queries The command and query messages available with the Fre quency module are listed in Table8 1 The interface jobs that are specific for the frequency module are explained in the following Message Command Query Message Command Query Average PAUse Continue RAnge Error REset File e SEtup e e Header STatus IDentify SYstem Key Version PArameter Working Table 8 1 Command and query message overview 8 1 2 Average The Average query is used for checking the average meas urement values over all scans for all frequency bands The syntax for the query Average and the response returned by Mediator appears in Fig 8 1 8 2 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 8 Interface Controlling Mediator via the Serial Interface To Mediator Ore 0E 3 See table From Mediator ORD OG HG Fig 8 1 Syntax for the Average query and Mediator response 980464e Sub Header LEG LMAx
7. 3 Average LEG 8 3 S L MAX i 8 3 Saved data vain ar 5 2 re a ng an incomplete scan ss Ta EE can NO nannaa 5 message overview eene 8 2 parameter line 4 3 Parameter Select kay rete d tene RS 2 4 Elapsed Pe eene 8 4 Selecting Inst sss 8 4 frequency bands eene 5 6 LEG 8 4 menu items 2 3 LMA Guevara 8 4 parameters 14 eee omine 5 6 MIE cessere REESE 8 4 spectrum parameter sese eee eee eee 4 4 BB1128 11 2238 Mediator 9 3 Frequency Analysis Software BZ7123 User Manual I ndex Sensitivity value Spectrum 1 4 Serial cursor 4 5 frequency analysis seene eee eee 1 4 display e NUMDET EEE 5 2 measurement results munne 5 2 5 3 Setting up parameters 1 9 AUtO Save sies Res 3 5 Standdrde orien iom remi et 3 Aux2 3 6 Start dwell time 3 4 frequency limits 13 3 date ai 1 11 5 2 frequency weighting 3 3 11 5 2 Input Output function 43 6 Stationary signals oer 1 4 3 4 measurement range 2 3 Store files 5 3 Mediator to start automatically 4 7 Summary of contents 1 2 No de 3 4 Switching octave bandwidth 3 3 between recall windows ee 5 5 Time 3 5 between recalled files 5 Time Weighting 3 4 2 Tolerance 3 5 SEU Ing S T bosted 6 3 SEtup Auto Save command eene 8 5 Auto Save query
8. 4 Overall Start Time 8 4 Measurement Window 2 2 Time Left 8 4 results iine 5 2 Underrange 8 4 Overload 5 3 PArameter zie need 8 3 instantaneous 4 5 SEtup latched e 4 5 Auto Saver nest ete 8 8 Overload eree enne 1 10 Auto Start 14 unner 8 8 Aux 1 8 8 P DUX 22 ken 8 8 Parameter ans 1 9 Bandwidth oo cece 8 8 default 7 2 Broadband Weighting 8 8 Elapsed query 8 4 Dwell THM weiss eee 8 8 fields 4 4 Eit Ayen ger ral 8 8 Inst query 8 4 No Of Scans 8 8 LEGEN e S Random Frontal sees 8 8 LMA query 4 SE quence d bcd 8 8 LMIn query 8 4 TI du EE 8 8 LP query 8 4 Ti Weighting 8 8 Overload query 8 4 ee MUSE eia 8 8 Scan Number query 8 4 A Fed n Wind Screen 8 8 selecting 2 3 SEtup 8 7 Start Date query 8 4 W s ig a Kr UD g Start Time query 8 4 Og text 2 REPE 1 3 LEq Vaadaa cervi ATOS 8 9 Time Left query 8 4 LMAX 8 9 Underrange query 8 4 LMIn 8 9 PArameter query 8 3 Working pepper Erre 8 9 Parameters selecting seene eee 5 6 Pause R Continue Key 2 4 Rand 1 5 mode ce 2 2 2 3 Rande RD E EA Pausing a measurement 4 5 KEE cu ba EN 2 373235 d KEY cene 2 2 set ng Window ossessione 3 2 Reca pe AL SSU E 5 4 Average Spectrum Window 5 5 rn S Broadband Measurement Window 5 5 P UT 5 4 files switching between 5 5 Q windows switching between 5 5 Query Reset THT 2
9. 5 6 BB1128 11 2238 Mediator 5 1 Frequency Analysis Software BZ7123 User Manual Chapter 5 Data Handling Data Storage 5 1 5 1 1 Data Storage Saved Data A measurement data file contains both overall measurement data and spedrum measurement results It consists of a group of set up data and a group of associated measurement data The set up data are e Serial number for Mediator unit e Measurement set up e Calibration data Measurement data are e Overall results e Broadband measurement results e Spectrum measurement results 1 3 or 1 1 octave 5 1 2 Set up Data Measurement Set up All measurement set up parameters that were used for the measurement Calibration Set up e Microphone type e Sensitivity e Calibration date 5 1 3 Measurement Data Overall Results e Start Date e Start Time 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 5 Data Handling Store Files Elapsed Time Overload Underrange Scan No Broadband Measurement Results Leg Lmax Lmin Spectrum Measurement Results The following data are always saved for each frequency in the 1 3 or 1 1 octave frequency bands Only the bands within the measured frequency range are saved Ley Lmax Emin e Marks Overload Underrange In printouts overloads are marked as o and underrange as U If an underrange occurs in a frequency band the associated value field appears as
10. If the first scan is saved without completing all frequency bands the value fields for the missing bands appear as N A 5 2 Store Files Automatically Saved Files If the Auto Save function in the Meas Control Window is switched on measurements are stored automatically with consecutive numbers How to Store the Current Measurement Manually 1 Press the Data Files key to display the Data Files menu 2 Pressthe Data Files key the FL select softkey or the p cursor key or to store the measurement with BB1128 11 2238 Mediator 5 3 Frequency Analysis Software BZ 7123 User Manual Chapter 5 Data Handling File Manager the displayed file name Saving File is displayed while saving takes place Single Scan If a single scan is selected you can store the frequency bands that have been completed 1 Press the w Pause Continue key to pause the meas urement 2 Store the measurement as described above Multiple Scans If more than one scan is selected only the complete scans are stored The stored scan is identical to the scan shown in the Averaged Spectrum Window 5 3 File Manager The File Manager is used to give an overview of the data files in the memory and has options for recalling printing and deleting these files TheDisk Summary option shows the memory status Refer to the Basic User Manual for informa tion about how to use the File Manager 5 4 Printing Data Printing is similar to
11. LMIn Table 8 2 Average queries Example reading the average L value Query from controller Average LEq From Mediator values in dB AVERAGE LEQ 48 4 46 6 52 5 51 3 8 13 PArameter The PArameter query is used for checking the selected meas urement parameters The syntax for the query PArameter and the response returned by Mediator appears in Fig 8 2 BB1128 11 2238 Mediator 8 3 Frequency Analysis Software BZ 7123 User Manual Chapter 8 Interface Controlling Mediator via the Serial Interface To Mediator OE OED See table From Mediator Parameter 5 PARAMETER Sub Header 3P Fig 8 2 Syntax for the PArameter query and Mediator response 980469e Sub Header ELapsed Inst LEq LMAx LMIn LP Overload Scan Number Start Time Start Date Time Left Underrange Table 8 3 Sub header and parameter settings for the PArameter query Example reading the broadband measured Leq value Query from controller PArameter LEq From Mediator value in dB PARAMETER LEQ 52 6 8 4 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual Chapter 8 Interface Controlling Mediator via the Serial Interface 8 14 SEtup The SEtup commands are used for setting up most of the measurement parameters in the Measurement Setting menu SEtup Commands
12. l j octave e 20Hz 12 5kHz l 3 octave Use the A V cursor keys to select the lower or upper frequency fields and set the desired range with the 4 gt cursor keys If you change the Bandwidth setting Mediator remembers the corresponding Limits setting Note The lower frequency must always be lower than or equal to the upper limit The upper or lower limits are au tomatically adjusted to fulfil this requirement Setting the upper and lower limits to the same value is equivalent to selecting a single frequency band with that centre frequency Setting Frequency Weighting for Broadband Data e C L BB1128 11 2238 Mediator 3 3 Frequency Analysis Software BZ 7123 User Manual Chapter 3 Measurement Set up Menu Measurement Set up Menu In the Broadband Wgt field you can select A C or L fre quency weighting This frequency weighting only applies to the broadband data Setting the Time Weighting e F S The Time Weighting field is used to set the time weighting used for both octave and broadband data You can select the standardised r and s time weightings 3 15 Measurement Control The Meas Control Window see Fig 3 3 is used to set up the parameters that affect the accuracy of a frequency anal ysis and whether a measurement is saved automatically or not Maas Control Mo of Scans Dwell Time Optimized Tolerance 0 5 JE Auto Save orf Fig 3 3 The Measurenent Control Window Setting t
13. the Recall Broadband Window you can also usethe 4 p keys to step down up through the file list BB1128 11 2238 Mediator 5 5 Frequency Analysis Software BZ 7123 User Manual Chapter 5 Data Handling Displaying Stored Files 5 5 3 Selecting Parameters and Frequency Bands Parameters In the Broadband Measurement Windows you can use the Y A and 4 p keys to select one of the four parameter lines and change the parameters exactly as in the Broadband Measurement Window Frequency Bands In the Recall Average Spectrum Window you can use the 4 gt keys to step the cursor through the frequency bands when the Print Cancel fields are highlighted If you select the Parameter Field you can use the lt K keys to display the Leg Lymin Or Lymax Spectra as required 5 6 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual Chapter 6 Specifications BB1128 11 2238 Mediator Frequency Analysis Software BZ 7123 User Manual Chapter 6 Spedifications 6 1 Specifications for Frequency Analysis Software BZ7123 Note These Specifications are additional to the Specifications described in the Basic User Manual System Requirements The 1 1 octave and 1 3 octave filter set must be installed in Mediator to support Frequency Analy sis Software BZ7123 i e Type 2238 A F A hardware upgrade installation of filter set 2238 MUF can be made at a Br el amp Kjaer service cen tre M
14. 25 Hz 31 5 Hz 40 Hz 50 Hz 63 Hz 80 Hz 100 Hz 125Hz 160 Hz 200 Hz 250Hz 315 Hz 400 Hz 500 Hz 630 Hz 800 Hz 1 kHz 1 25 kHz 1 6kHz 2kHz 2 5kHz 3 15kHz 4kHz 5kHz 6 3kHz 8kHz 10kHz 12 5 kHz BB1128 11 2238 Mediator 6 3 Frequency Analysis Software BZ 7123 User Manual Chapter 6 Spedifications C CE mark indicates compliance with EMC Directive EMC Emission EN 50081 1 Generic emission standard Part 1 Residential commercial and light industry EN 50081 2 Generic emission standard Part 2 Industrial environment CISPR 22 Radio disturbance characteristics of information technology equipment Class B Limits FCC Rules Part 15 Complies with the limits for a Class B digital device EMC Immunity EN 50082 1 Generic immunity standard Part 1 Residential commercial and light industry RF immunity implies that sound level indications of 50 dB or greater will be affected by no more than 0 5 dB EN 50082 2 Generic immunity standard Part 2 Industrial environment RF im munity implies that sound level indications of 65 dB or greater will be affected by no more than 0 5 dB These levels of immunity are 9 dB better than required by IEC 1672 Note The above conformance is guaranteed only when using the included optional accessories Br el amp Kj r reserves the right to change specifications and accessories without notice 6 4 2238 Mediator Br el amp Kjeer Frequency Analysis Sof
15. Advanced Test Equipment Rentals C f lished 1981 www atecorp com 800 404 ATEC 2832 eS bb112211 book Page 1 Thursday November 26 1998 9 23 AM 2238 Mediator Integrating Sound Level Meter Frequency Analysis Software BZ 7123 November 1998 Bruel amp Kj r BB1128 11 Trademarks 2238 Mediator is a trademark of Br el amp Kj r Sound amp Vibration A S Copyright 1998 Bruel amp Kj r Sound amp Vibration Measurement A S All rights reserved No part of this publication may be reproduced or distributed in any form or by any means without prior consent in writ ing from Bruel amp Kjar Sound amp Vibration Measurement A S N rum Denmark 2238 Mediator Frequency Analysis Software BZ 7123 User Manual Br el amp Kj r Contents Introduction About this manual and the contents of the Frequency Analysis module Key Functions Explains the function of the front panel keys Measurement Set up Menu Explains how to set up parameters in the Measurement Set up menu Measuring Explains how to use the three measurement windows the back erase function and how to set up an Auto Start Data Handling Explains how to save recall and delete data in the Frequency Analysis module and how to switch between displays Specifications Specifications for the Frequency Analysis module Appendix 1 General List of default parameters general messages and error messages
16. Analysis module 1 3 3 General Parameters Table1 4 lists the general parameters available with the Fre quency Analysis module 2238 Mediator Frequency Analysis Software BZ 7123 User Manual Br el amp Kj r Chapter 1 Introduction Frequency Analysis Functions General Parameters Default Screen diin Parameter Parameter Definition Elapsed Time Elapsed Time The amount of time that has passed since the current measurement began measurement time excluding pauses Start Time Start Time The start time for the current meas urement Start Date Start Date The start date for the current meas urement Time Left Time Left The amount of time that remains before the measurement is complete Scan No Scan No Shows the current scan number and the total number of scans Table 1 4 General parameters available with the Frequency Analysis mod ule 1 4 Frequency Analysis Functions 1 4 1 Back erase The back erase function allows you to delete any required number of consecutive frequency bands in a frequency anal ysis This is particularly useful if a disrupting noise occurs during a measurement 142 Auxl Aux1 is set up as an AC Output and cannot be changed BB1128 11 2238 Mediator 1 11 Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Frequency Analysis Functions 1 43 Aux2 In addition to the DC Output function in the basic version Aux2 can be s
17. Averaging spectra ose eee 1 5 No Of Scans 8 6 Random Frontal 8 6 B Recall st cete 8 6 Back erdse eee e e Ee 1 11 4 5 SAVE renti EAE SES DERE RSS SER 8 6 BB1128 11 2238 Mediator 9 1 Frequency Analysis Software BZ7123 User Manual I ndex SE quence Window 8 7 3 6 Time 8 7 Instantaneous value 4 6 Time Weighting 8 7 Interrupting a measurement ou eee 4 5 TOlerance 8 7 Wind Screen 8 7 K Controlling Mediator via the interface 8 2 Keys Conventions in this Manual 1 3 Backlight e 2 4 Cursor keys 2 2 Calibrate 2 2 Cydical signals ku erme 1 5 Cancel 2 4 Data Files desee esee 2 2 D definitions iaces cerea rentene 2 2 DAT recorder ses 356 Left Right Arrow 2 3 Data Meas Result 2 3 SEE 2 2 Pause Continue 2 4 files menu Ls 2 2 5 3 pictograms ET 2 2 DC Power 2 2 EFIDUE Loss T 3 6 Range 2 3 Output 6 2 Reset 2 3 Default parameters 7 2 Select 2 4 Deleting files 5 4 Set up 2 2 Detectors 6 2 System 1255754585 2 2 Disk Summary op i 5 4 UP DOWN Arrow EEE EEE 2 2 Display layout 4 3 Displaying stored files aa 5 L Dwell time sse 1 5 3 4 Left Right Arrow Key eee 2 3 Limits frequency range 43 3 E LXeq reserved 1 9 1 10 Elapsed time seen 1 11 5 3 LXpk 1 10 6 4 LXYinst w
18. EYS sa NN 1 3 ha iun OE 1 9 9 4 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual
19. K F12K5 Char Sets the Lower Limit E g F31_5 31 5 Hz To set the limits send for example the command with the upper limit first SE L F3K15 F20 No_Of_Scans e 1 99 NR1 Sets the number of scans Random Frontal Random Frontal Char Sets Random or Frontal frequency correction Recall 0 4 NR1 Recall measurement set up 0 to 4 0 is default set up SAve NR1 Saves measurement set up in memory 1 to 4 Table 8 4 cont Sub header and parameter settings for the SEtup command 2238 Mediator Frequency Analysis Software BZ 7123 User Manual Br el amp Kj r Chapter 8 Interface Controlling Mediator via the Serial Interface Parameter Setting Sub Header Comments No Setting Type SEquence OFf Char Switches the Auto Start ON sequence On or Off Time 1 0 60 NR1 Minutes 2 0 59 NR1 Seconds Sets the measurement time for each frequency band if Dwell Time is Fixed Time Weighting Fast Char Sets the time weighting to Slow Fast or Slow TOlerance T_0_25 Char 0 25 0 5 or 1 dB tolerance T 050 Used if Dwell Time is T 1 Optimized Wind Screen OFf Char Switches the windscreen ON frequency correction On or Off Table 8 4 cont Sub header and parameter settings for the SEtup command SEtup Queries The syntax for the query SEtup and the response returned by Mediator ap
20. The SEtup commands except for Auto Start use the syntax illustrated in Fig 8 3 To Mediator E EO EHE See table From Mediator OEO EE See text Fig 8 3 Syntax for the SEtup command Parameter Setting Sub Header Comments No Setting Type Auto_Save OFf Char Switches autosave on of off ON Aux 2 Out Char Sets Aux 2 to DC Output Trigger In Sets Aux2 to Trigger Input Trigger Out Sets Aux2 to Trigger Out put Bandwidth Octave 3 Char Setthe bandwidth to 1 3 or Octave 1 1 1 octave Broadband A Char Sets A C or Linear _Weighting C weighting Lin Dwell Time Optimized Char Sets the measurement time Fixed for each frequency band Table 8 4 Sub heade and parameter settings for the SEtup command BB1128 11 2238 Mediator Frequency Analysis Software BZ 7123 User Manual 8 5 Chapter 8 Interface Controlling Mediator via the Serial Interface Sub Header Parameter Setting No Setting Type Comments Limits 1 F20 F25 F31 5 F40 F50 F63 F80 F100 F125 F160 F200 F250 F315 F400 F500 F630 F800 F1K F1K25 F1K6 F2K F2K5 F3K15 F4K F5K F6K3 F8K F10K F12K5 Char Sets the Upper Limit E g F3K15 3 15 kHz F20 F25 F31_5 F40 F50 F63 F80 F100 F125 F160 F200 F250 F315 F400 F500 F630 F800 F1K F1K25 F1K6 F2K F2K5 F3K15 F4K F5K F6K3 F8K F10
21. allows you to specify a measurement time Tpwal which is always constant irrespective of frequency band and octave bandwidth see Time below Use the A Y cursor keys to select the minute or second fields and set the desired time with the p cursor keys The Fixed time can be set from 1 second to 60 minutes Setting up Auto Save e On e Off The Auto Save function can be switched on or off When activated it will automatically save a measurement when it is finished i e when the specified number of scans is com BB1128 11 2238 Mediator 3 5 Frequency Analysis Software BZ 7123 User Manual Chapter 3 Measurement Set up Menu Measurement Set up Menu 3 1 6 pleted A measurement is not saved when the pause function is activated Measurements are stored with consecutive num bers in the File List Setting up the Input Output Function The Input Output Window controls the function of the Aux 1 and Aux2 inputs outputs See Fig 3 4 Cancel Input Output Hux 1 HC Output Aus 2 Fig 3 4 The Input Output Window Aux1 The aux 1 field is set to AC Output and cannot be accessed The AC output signal is fed to the Aux 1 socket The AC output corresponds to the constant output from the scanned octave bands with filter transients Full scale indication corresponds to 1V RMS This output sig nal can be used for example for recording the measured signal on a DAT recorder Aux2 e DC Output e Trigger Inp
22. cific for the Frequency Analysis module Measurement Set up Menu Frequency Analysis Software BZ7123 contains the menu items shown in Fig 3 1 Heas Control Recall Setup Corr Filters Input Dut put Auto Start Fig 3 1 The Measurement Set up menu two windows Range There is no General Window in the Frequency Analysis module this means that the Range Setting menu must be accessed by pressing the agd Range key Setting Frequency Weightings The weightings Window is used for setting up frequency and time weightings for octave and broadband data see Fig 3 2 Note that 1 1 and 1 3 octaves are always measured with de tector 1 and broadband data is measured with detector 2 Time weighting settings apply to both detectors 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 3 Measurement Set up Menu Measurement Set up Menu Time Weighting Fig 3 2 The Waghtings Window Setting Bandwidth e 1 3 octave e 1 1 octave Select the desired option in the Bandwidth field Note To run Frequency Analysis Software BZ7123 the 1 1 octave and 1 3 octave Filter Set must be installed in Mediator Setting Frequency Limits for Octave Bands For setting the frequency range for the frequency analysis The Limits parameter field automatically changes to 1 1 or 1 3 octave frequency steps according to the Bandwidth field above The default values are e 31 5Hz 8kHz
23. d of Start Scan 1 Scan 2 Scan Band Band Band Ter TrastSlow well Broadband Data 9H iN 980483e Fig 1 1 Time sequence for a measurenent consisting of a number of scans Each scan is a serial frequency analysis which consists of a number n of frequency bands The measurenent time re quired for each frequency band is the sum of the three time intervals T Filter Trast Slow and Tpwal see bd ow When making a frequency analysis with Mediator running Frequency Analysis Software BZ 7123 the complete result of a measurement is a spectrum and overall broadband values for the measurement time Since a frequency analysis is done by measuring in each frequency band serially contrary to measuring all bands in parallel the method is most useful for fairly stationary sig nals for example those emitted by rotating machinery Highly 1 4 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Serial Frequency Analysis fluctuating signals for example from fly overs and concerts cannot be measured reliably using serial analysis Furthermore to get a reliable result for a random signal the measurement time in a frequency band depends upon the centre frequency of the band At high frequencies only a short time is needed at lower frequencies the measurement time increases The time that is used for measuring in each band is referred to as dwell time Tpwej For further
24. e shown in Fig 4 6 is displayed Notes An Auto Start only takes effect if Mediator is switched off at the time the Auto Start is supposed to run If Mediator is already switched on the Auto Start is cancelled Mediator keeps measuring until the selected number of scans are finished or until manually stopped 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Setting a Measurement to Start Automatically E Auto Start activated Bz7123 1998 How 23 15 45 00 Press OFF or Hait 4 peac Fig 4 6 Confirmation of an Auto Start when switching Mediator off Mediator switches on approximately 30s before the set time for an Auto Start This allows Mediator to settle and start measuring at exactly the set time BB1128 11 2238 Mediator 4 9 Frequency Analysis Software BZ 7123 User Manual 2238 Mediator Frequency Analysis Software BZ7123 User Manual Br el amp Kj r Chapter 5 Data Handling SL DAG SION eee 5 2 Saved Data inei e xe EDO ER REUS 5 2 Set up Data eene tete ete oci 5 2 Measurement 6 1 sir ne ra ane 5 2 5 2 Store T 5 3 53 File Man AGEN a sete Lbs ee 5 4 54 Printilig Dalba ucsect ned o Net eH 5 4 5 5 Displaying Stored Files wesc 5 5 Switching Between the Recall Windows 5 5 Switching Between Recalled Files 5 5 Selecting Parameters and Frequency Bands
25. easurement data The Working and Average Spectra are also reset If a meas urement is in progress it continues immediately after reset If the in strument is paused it is still paused after pressing Reset Note f a measurement has been in progress for more than a minute a warning is displayed and you must confirm the command before any data is deleted Meas Results 3 Pressthis in any of the set up men us to return to one of the Measure ment Windows If menu changes have not been saved they are can celled BB1128 11 2238 Mediator 2 3 Frequency Analysis Software BZ 7123 User Manual Chapter 2 Key Functions Key Functions Frequency module Use this key to switch between the Broadband Measurement Window and the Working and Average Spectrum Windows Pause Continue Uc Press this to pause continue the current measurement When re suming a measurement after paus ing Mediator the measurement is continued without resetting data or the timer Frequency module Pressing this key after a measurement is fin ished performs a reset and starts a new measurement Pressing it during a measurement when the Working Spectrum Win dow is displayed activates the Back Erase mode see Select Select M1 Functions as Select Save Recall or ok depending on the cursor position in the current menu The Menu function dis plays the File Manager Options Window Frequency module Functions as Back E
26. easurements The available measurement parameters are listed in the table below Detector 1 measures 1 1 or 1 3 octave band data while Detector 2 measures broadband data You can select A C and L fre quency weighting for broadband data and F or S time weightings for both detectors Symbol Key for measurement parameters X Frequency weighting A C or L Y Time weighting F or S Lxvinst Time Left Time Detector 1 Detector 2 RMS RMS Spectrum Broadband Stored Leq Lxeq Lymax Lxymax Lymin Lxymin Overload 6 Underrange Start Date Start Time Elapsed Time Scan No Instantaneous display only Lxyp Measuring Ranges Linear Operation Range 80dB adjustable to give full scale readings in 10dB steps over the range 80 140dB Upper Limit RMS for Crest Factor z 10 17 dB below full scale reading Detectors Simultaneous detection of spectrum and broad band parameters Spectrum 1 1 octave and 1 3 octave band filters with two exponential time weightings F or S and a linear averaging detector Broadband Two exponential time weightings F or S and a linear averaging detector Selectable frequency weighting A C or Lin Overload Detector Monitors all the frequency weighted channels Auto Start The Mediator supports four Auto Starts which al low set up of measurement start times up to a month in advance Aux 1 Output Connect
27. equency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Serial Frequency Analysis Tritter S Tpwen Optimized s T Freq constr 0 25 dB 0 5 dB 1 0dB Hz ue i ESU oct oct 1 3 14 1 3 1 4 1 3 14 oct oct oct oct oct oct 12500 0 5 J 0 25 0 25 0 25 10000 0 5 0 25 0 25 0 25 8000 05 0 5 025 025 025 O25 O25 0 25 6250 05 0 25 0 25 0 25 5000 0 5 0 26 0 25 0 25 4000 05 0 5 033 025 025 O25 025 0 25 3125 05 0 41 0 25 0 25 2500 05 0 52 0 25 0 25 2000 05 0 5 0 65 025 025 O25 O25 0 25 1600 0 5 SS Gee 0 25 0 25 1250 05 1 04 0 26 0 25 1000 0 5 0 5 131 043 033 0 25 0 25 025 800 0 5 1 64 0 41 0 25 625 0 5 2 07 0 52 0 25 500 055 05 261 086 065 0 25 O25 0 25 400 0 5 3 28 0 82 0 25 315 0 5 4 13 1 03 0 26 250 0 5 0 7 520 171 130 043 032 025 200 0 5 6 55 1 64 0 41 Table 1 1 Setling and dwell times used for calculating the total meas urement time BB1128 11 2238 Mediator Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Serial Frequency Analysis
28. et up as a trigger input or a trigger output 1 44 Measurement Set up Menu The Measurement Set up menu contains the following items in the Enhanced module e weightings for selecting 1 1 or 3 octave bands for setting the frequency range and for setting broadband frequency weighting and time weighting Measurement Control for setting up number of scans dwell time and Auto Save Correction Filters for selecting correction filters for sound incidence and windscreen Input Output for selecting DC Output Trigger Input or Trigger Output for the Aux 2 sockets Auto Start for selecting an Auto Start Save Setup for saving a measurement set up Recall Setup for recalling a measurement set up 1 12 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual Chapter 2 Key Functions 2 1 Key Functi ons ver 2 2 BB1128 11 2238 Mediator 2 1 Frequency Analysis Software BZ 7123 User Manual Chapter 2 Key Functions Key Functions 2 1 Key Functions Each key on Mediator s front panel is marked with a picto gram This section gives a brief explanation of the keys Power OD Calibrate System gr Data Files Set up i Up Down Arrows A V Press this to switch M ediator on or off The instrument starts in pause mode Press this to calibrate Mediator Press this to display the System menu for configuring the instru ment and for changing application programs Press
29. eters Table1 3 lists the broadband parameters available with the Frequency Analysis module These parameters can be dis played in the Broadband Measurement Window The X and Y suffixes in the parameter names refer respectively to fre quency weightings A C or L and time weightings F or S BB1128 11 2238 Mediator 1 9 Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Measurement Parameters Broadband Parameters Detector 2 Default Freq Time Parameter screen Definition Weight Weight parameter ing ing Lxeg LCeq Equivalent continuous A C level for the duration of or L the measurement all scans as defined by IEC 1672 LxvMax LCFMax Max Lxyp value detected A C F or S within the elapsed time or L LxvMin LCFMin Min Lxyp value detected A C F or S within the elapsed time or L Overload Overload The percentage of time m that an overload occurred during a measurement Underrange Under The percentage of time range that an underrange occurred during a meas urement Instantaneous Parameters Display Only Lyyinst LCFInst Instantaneous value of A C F S RMS level or L and I Lxyp LCFp Sound pressure level A C F S SPL or L and I Table 1 3 Broadband parameters available with the Frequency
30. he Number of Scans No of Scans allows you to set up the desired number of frequency scans from 1 to 99 This is the number of averages that is used to display the result in the Average Spectrum Window As a general rule frequency analysis should be per formed on stationary signals However with appropriate av eraging a good representation can be made for a number of non stationary signals Setting the Dwell Time Dwell Time is used for setting the measurement time for each frequency band Tpwe in the frequency analysis 3 4 2238 Mediator Briel amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 3 Measurement Set up Menu Measurement Set up Menu Optimized e Fixed When Optimized is selected Mediator automatically calcu lates the optimum measurement time Tpwae based on the current frequency band and the specified measurement tol erance see Tolerance below Refer to section xx for infor mation about filter characteristics and calculation of measurement ti me For normal frequency analysis you should select Optimized Setting Tolerance Time Depending on whether Optimized or Fixed is selected in the Dwell Time parameter field this parameter field appears as Tolerance Or Time respectively Tolerance e 0 25 0 5 1 0dB Specifies the measurement tolerance when Optimized is se lected Lower tolerance higher accuracy increases the meas urement time Fixed e 00 01 60 00 Fixed
31. information refer to Br el amp Kjar publication Frequency Analysis BT 0007 1 2 2 Dwell Time As stated above the required measurement time varies for different frequencies If the signal is non stationary for ex ample fluctuating in a cydical manner even more measure ment time may be required to average the fluctuations Mediator with BZ7123 offers three ways of controlling fre quency analyses e Optimized dwell time with three levels of statistical error or tolerance see below Fixed user selected dwell time Averaging of several spectra with one averaged spectrum as the result Optimized and fixed dwell times are explained below Aver aging of spectra is explained in section 3 1 5 Optimized Dwell Time Dwell times can be optimized in the sense that the reliability or tolerance in all measured frequency bands is the same This is what Mediator does when you select Optimized dwell time When Optimized is selected you can choose the re quired Tolerance see section 3 1 5 The options are e 025GB 0 5dB and 1 0dB Choosing for example 0 5dB tolerance means that there is 6796 probability that the measurement results in all selected BB1128 11 2238 Mediator 1 5 Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Serial Frequency Analysis bands are within 0 5dB for a normally distributed random signal It is important to note that the required tolerance influences the t
32. le scan 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Measurement Result Windows is performed the result of this scan is also transferred to the Averaged Spectrum Example If you select five scans of the 29 1 3 octave bands and start the measurement you will see the Working Spec trum being updated as the frequency bands are measured The Averaged Spectrum has no content until the first scan of all 29 bands is completed At that time it is updated with the results of the first scan and shows that this is result 1 out of 5 scans Scan No 1 5 When scan no 2 starts the Working Spectrum is deared and shows the results of the second scan as the frequency bands are available Next up date of the Averaged Spectrum is when the second scan is complete and so on until all five scans are completed At this time the Averaged Spectrum shows the result of five averaged spectra and the Working Spectrum shows the result of the last scan scan no 5 If the measurement is saved automat ically or manually it is the Averaged Spectrum that is saved If you select for example 10 scans and choose to stop the measurement after three scans by pausing the measurement in the middle of the fourth scan the Averaged Spectrum is the result of the three completed scans i e you always save the result of completed scans and any half finished scan in this example the fourth scan is not sa
33. ment Window the Working Spec trum Window and the Average Spectrum Window Gives instructions for using the back erase function and for setting up an Auto Start Chapter 5 Data Handling contains information about the parameters that are saved in the Frequency Analysis module how to save recall and delete data and how to switch between displays Chapter 6 Specifications contains technical specifi cations for the Frequency Analysis module Appendix 1 General lists the default parameters the general messages and the error messages that are specific for the Frequency Analysis module Appendix 2 Interface gives instructions for using the interface commands and queries for the Frequency Anal ysis module Index 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction About this Manual 1 11 2 About this Volume This volume of the User Manual deals only with the instruc tions and functionality that are specific for the Frequency Analysis module Frequency Analysis Software BZ 7123 For information about the general operation and functionality of Mediator please refer to the Basic User Manual BB 1119 Conventions Used in this Manual Keys References to keys on the 2238 Mediator are shown with the key s pictogram as it appears on the instrument for example Zr Refer to section 2 1 for a complete list of key pictograms and their functions Soft Key
34. only set up an Auto Start for the cur rently running application module If you want another ap plication module to start the Auto Start must be set from that module To set up an Auto Start l Select Auto Start from the Measurement Set up menu If no Auto Start is set up for example for Auto Start no 1 the display appears as Fig 4 4 The basic Auto Start Window BB1128 11 2238 Mediator 4 7 Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Setting a Measurement to Start Automatically 4 Usethe 4 cursor keys to select one of the four Auto Starts and press ok If the Auto Start is active the display will show the assodated application module as well as the set up number and the start time 1998 Now 23 10 03 40 Use Setup na 1 Fig 4 5 Auto Start set up Use the A Y cursor keys to select the Application field and use the p cursor keys to select None or BZ7123 None means that the Auto Start is not active if previously set the set up parameters will be deleted if you press ox If the Auto Start is already activated by another application module for example BZ7124 the number of this application module is also among the choices The display will appear similar to Fig 4 5 Se up the Date Time and Use Setup no fields as required The date and time can be set to one month ahead Press ok to activate the Auto Start When switching Mediator off the messag
35. or 2 pin LEMO AC Output Signal Range adjusted AC output with the frequency band currently selected on de tector 1 Short circuit protected Output 1 V RMS corresponding to full scale indi cation Max Load 10kQ 1nF Output Impedance Typically 100 Q Aux 2 Output Connector 2 pin LEMO Can be used as a DC output a trigger input or a trigger output DC Output Output Signal DC version of signal on RMS de tector 1 Fast Inst Delayed 0 8s Short circuit protected Output 0 to 4 0 V DC 50 mV dB Update Rate 160 times per second Max Load 10kQ 1nF Output Impedance Typically 100 Q Trigger Input Voltage Range 0 to 4V Trigger Level 2 V on positive edge 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 6 Specifications Trigger Output Trigger Output Pause 0 V Measuring 4 V Settling Time From Power On lt 10s 6 2 Additional Specifications for Filter Set Standards Conforms with the following EN61260 IEC 1260 1995 Octave and 1 3 0c tave Bands Class 1 e ANSIS1 11 1986 Octave and 1 3 octave Bands Order 3 Type 1 D Optional Range Octave and 1 3 octave Band Filters Frequency Rating System Base 10 Reference Attenuation 0 dB Linear Operating Range As Indicator range Nominal Octave Band Centre Frequencies 31 5Hz 63Hz 125Hz 250Hz 500Hz 1kHz 2kHz 4 kHz 8kHz Nominal 1 3 octave Band Centre Frequencies 20 Hz
36. otal measurement time For example scanning all 1 3 octave bands with 0 25dB tolerance gives a total measure ment time of 5 minutes and 50s changing the tolerance to 1 0 dB gives 55s measurement time Also note that most of the measurement time is spent at low frequencies The re quired measurement time can be read directly from the dis play in the Time Left field in the Working Spectrum Window and the Broadband Measurement Window Fixed Dwell Time As an alternative to Optimized dwell time you can select a Fixed dwell time In this case the same amount of time is used in all 1 1 or 1 3 octave bands The dwell time can be set in the range from 1second to 60 minutes see section 3 1 5 Using Fixed dwell time is most useful when measuring peri odically fluctuating signals All fluctuations in the signal must be covered during the measurement time Total Measurement Time The time required to make a frequency analysis is not simply the sum of the dwell times see Fig 1 1 For each band to be measured M ediator must switch on the required octave band filter and ensure that the filter and the detector are settled The filter transient time is referred to as Tr jjte and the time it takes to reset the Fast and Slow time constants is referred to as Trast slaw T he total measurement time is the sum of dwell times and settling times i e Towai Trilter T Trast Slow These are shown in Table 1 1 2238 Mediator Br el amp Kj r Fr
37. pears in Fig 8 4 To Mediator Ore 063 See table From Mediator OEO TTT See table 980216 1e Fig 8 4 Syntax for the SEtup query and Mediator response BB1128 11 2238 Mediator 8 7 Frequency Analysis Software BZ 7123 User Manual Chapter 8 Interface Controlling Mediator via the Serial Interface Sub Header Auto Start 1 Auto Start 2 Auto Start 3 Auto Start 4 Auto Save Aux 1 Aux 2 Bandwidth Broadband Weighting Dwell Time Limits No Of Scans Random Frontal SEquence Time Time Weighting TOlerance Wind Screen Table 8 5 SEtup queries Example checking the Tolerance set to 0 5 dB Query from controller SEtup TOlerance From Mediator SETUP TOLERANCE T 0 5 8 8 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual Chapter 8 Interface Controlling Mediator via the Serial Interface 8 15 Working To Mediator OEO See table From Mediator HE OEO 980465e Fig 8 5 Syntax for the Working query and Mediator response The Working query is used for checking the working meas urement values for the current scan in all frequency bands The syntax for the query Working and the response returned by Mediator appears in Fig 8 5 Sub Header LEq LMAx LMIn Table 8 6 Working queries
38. rase key in the Working Spectrum Window when the Back Erase mode is activated Pressing the fF key deletes the frequency bands back to and induding the band where the cursor is posi tioned Cancel Functions as Cancel Undo or Close depending on the cursor position in the current menu Backlight amp Switches the display s backlight on or off To save batteries the back 2 4 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 2 Key Functions Key Functions light switches off automatically af ter 30 seconds BB1128 11 2238 Mediator 2 5 Frequency Analysis Software BZ 7123 User Manual 2238 Mediator Frequency Analysis Software BZ7123 User Manual Br el amp Kj r Chapter 3 M easurement Set up Menu 3 1 Measurement Set Up Menu 3 2 Intfodudttion 43 secant eet e eee ik 3 2 Measurement Set up Menu sees eee eree eee eee 3 2 Range etie vb ddp ient ub e epe aedis 3 2 Setting Frequency Weightings sss sse sees eee eee eee 3 2 Measurement Control eee 3 4 Setting up the Input Output Function 3 6 BB1128 11 2238 Mediator 3 1 Frequency Analysis Software BZ 7123 User Manual Chapter 3 Measurement Set up Menu Measurement Set up Menu 3 1 3 1 1 3 1 2 3 1 3 3 1 4 Measurement Set up Menu Introduction This chapter explains how to set up measurement parameters that are spe
39. replaced with a lt Back Erase gt soft key Fig 4 3 The Back Erase function 3 Usethe lt p cursor keys to move the spectrum cursor to the frequency band to which you want to delete the frequency bands 4 Press the 7 lt Back Erase softkey to back erase All the frequency bands to the left of the cursor and the frequency band at which the cursor points are deleted You can delete more frequency bands by moving the cur sor to the right and pressing lt Back Erase gt again 2238 Mediator Briel amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Setting a Measurement to Start Automatically 4 3 You can continue the measurement by pressing the x Pause Continue key The Time Left field is updated to show the actual remaining measurement time Note If you do not back erase any frequency bands the measurement will continue from the frequency band where it was paused Setting a Measurement to Start Automatically Mediator can manage up to four auto starts Auto Starts are shared among the application modules that support them Each Auto Start has a number 1 through 4 and is set to start a specific application at a specified time up to one month ahead using a specified set up See also section 3 1 5 in the Basic User Manual From a specific software module in this case F requency Anal ysis Software BZ 7123 all four Auto Starts can be seen and selected but you can
40. rloads in the spectrum windows are only detected during the measurement periods Tpwej i amp no overloads are detected during the filter and detector settling periods 4 16 Pausing Interrupting a Measurement In the Working Spectrum and Broadband M easurement Win dows you can use the key to pause continue an ongoing measurement When resuming a measurement after pausing Mediator the measurement is continued without resetting data Pressing this key after a measurement is finished per forms a reset and starts a new measurement If the Working Spectrum Window is displayed and you press the key during a measurement the Back Erase mode is activated see Erasing Bad Data below BB1128 11 2238 Mediator 4 5 Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Erasing Bad Data 4 1 7 4 2 Instantaneous Value A separate column on the right hand side of the spectrum display shows the instantaneous value Lxynst of the RMS level and is updated five times per second The associated frequency weighting is shown in the lower right hand corner of the display Erasing Bad Data The back erase function allows you to delete any number of frequency bands in the current scan This is particularly useful for deleting a non typical noise occurrence during a measurement 1 Usethe Y key to display the Working Spectrum Window during a measurement 2 Press the x Pause Continue key The Time Left line is
41. s Mediator has two soft keys that have different functions depending on the current context The soft keys functions are denoted by chevrons and courier type face The current functions of the soft keys are always shown on the display The R soft key can have the following functions select Save Ok Menu Of Back Erase gt The TY soft key can have functions Cancel Undo Or Close This is similar to the functionality from the familiar Windows en vironment Parameter Text Text which refers directly to text on the instrument s screen or printouts is indicated using a Courier type face For example Press Y until Language is highlighted in the System menu Sockets Reference to sockets is made in bold type face for example Aux 1 BB1128 11 2238 Mediator 1 3 Frequency Analysis Software BZ 7123 User Manual Chapter 1 Introduction Serial Frequency Analysis 12 Serial Frequency Analysis 12 1 What is Serial Frequency Analysis A 2238 Mediator with a filter set installed can measure sound levels in nine 1 1 octave bands from 31 5Hz to 8kHz or 29 1 3 octave bands from 20Hz to 12 5 kHz A serial frequency analysis is a number of consecutive measurements performed in each of the selected frequency bands The result is a spec trum measured over some time the elapsed time or meas urement time During the same period a broadband measurement is performed see Fig 1 1 Scan En
42. sing Bad Data 4 6 4 3 Setting a Measurement to Start Automatically 4 7 BB1128 11 2238 Mediator 4 1 Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Measurement Result Windows 4 1 Measurement Result Windows Three different measurement result windows are used for the frequency analysis module Working Spectrum Window Av eraged Spectrum Window and Broadband Measurement Win dow The result windows are illustrated in Fig 4 1 Use the ye Meas Results key to change between the windows in the mentioned order IT iHe Left 00 00 00 D B can Ho LikHzrMax 45 5936 110 T LcrMin 3e 446 LcrMin 32 4JB Loe 46 936 Time Left 00 00 00 Fig 4 1 The Working Spectrum Window the Averaged Spectrum Win 4 1 1 dow and the Broadband Measurement Window shown in that order Working and Averaged Spectrum Windows The Frequency Analysis module has two spectrum displays The Working Spectrum Window shows the results so far of the current scan of the frequency bands i e it reflects the currently ongoing measurement The Average Spectrum Win dow shows the cumulative results of the selected number of Scans The result of a measurement is what is in the Averaged Spectrum This spectrum is updated whenever a scan of the frequency bands is completed if more than one scan is per formed each new complete scan is averaged with the current contents of the Averaged Spectrum When only a sing
43. the Basic module the main difference is that the Print Options menu does not exist i e all set up and measurement parameters are printed You can print the current measurement or you can print a single or a number of recalled files via the File Manager or by using the R Print softkey 5 4 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual Chapter 5 Data Handling Displaying Stored Files 5 5 Displaying Stored Files If a stored file has been recalled from the File Manager the data is displayed in two recall windows as illustrated in Fig 5 1 Fig 5 1 The Recall Average Spectrum and the Recall Broadband M es urement Windows separate windows Except for the instantaneous parameters and overload indi cation these windows are similar to the Average Spectrum Window and the Broadband M easurement Window 5 5 1 Switching Between the Recall Windows Usethe A key to switch between the Recall Average Spec trum and Recall Broadband Measurement Windows Note Both A keys switch between the windows when they reach the top or bottom of the current window Use the Meas Results key to return to the measure ment window which was active when you recalled the stored files 55 2 Switching Between Recalled Files Use the Eh Data Files key to step through the files if more than one file has been selected in the File Manager If the cursor is positioned in the Print Cancel fields in
44. this to select the Data Files menu The menu options in this window allow you to save and print files and to access the File Manager facility Frequency module If more than one measurement file is recalled you can use Eh to switch between the recalled files Press this to access step through the set up options in the Measure ment Set up menu Press these keys to step up down in the menu items in the selected window Frequency module Use the keys to enter exit edit mode in the Broadband Measurement Window and to select the parameter field in the Working and Averaged Spec trum Windows You can also use these keys to switch between the Averaged Spec 2 2 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 2 Key Functions Key Functions trum and Broadband M easurement Windows when recalling measure ments Left Right Arrows p Press these keys to select the pa rameters in the selected window Note For the sake of consistency the A V keys are always used to select menu items and the 4 gt keys are always used to se lect values Frequency module Use the 4 gt keys to step the cursor through left or right the frequency bands in the Working and Averaged Spectrum Windows Range ad Press this to access the Range Set ting menu Usethe lt keysto step through the available meas urement ranges or scroll with the add key Reset z Resets the current m
45. tion Filter settings When a pause is made during the first scan and you try to save the measurement When a pause is made during the second or later scans and you try to save the measurement Solution Press ok to change the set up the measurement will be reset Press Cancel to skip without chang ing Press ok to save the spectrum and return to the Measurement Window Press Cancel to go to the Data Files Window without sav ing the measure ment The measurement can be continued Press Ok to save the averaged spectrum and return to the Measurement Win dow Press Cancel to return to the Data Files Window with out saving the measurement The measurement can be continued BB1128 11 2238 Mediator Frequency Analysis Software BZ 7123 User Manual Chapter 7 Appendix Error Messages 7 3 Error Messages The following warning may appear when using the Frequency Analysis module Lter set lled When you activate the Frequency Analysis module without having the 1 1 octave and 1 3 octave filter set installed If you press Ok the program will display the Measurement Window and func tion normally how ever you cannot make any 1 1 octave or 1 3 octave meas urements 2238 Mediator Frequency Analysis Software BZ7123 User Manual Br el amp Kj r Chapter 8 Interface 8 1 Controlling Mediator via the Serial Interface 8 2 Commands and OUueries
46. tware BZ 7123 User Manual Chapter 7 Appendix 7 1 List of Default Dar ame terse eee 7 2 7 2 MESSBUS de SR 7 2 Fa NSR 7 4 BB1128 11 2238 Mediator 7 1 Frequency Analysis Software BZ 7123 User Manual Chapter 7 Appendix List of Default Parameters 7 1 List of Default Parameters Note These default parameters are in addition to those de scribed in the Basic User Manual Menu Set up Parameter Default Value Weightings Bandwidth 1 3 Octave Limits 1 3 Octave 20 12 5 kHz Limits 1 1 Octave 31 5 8 kHz Broadband Wgt C Time Weighting F Meas Control No of Scans 1 Dwell Time Optimized Tolerance 0 5 dB Fixed 00 01 Auto Save Off Input Output Aux 1 AC Output fixed Aux2 DC Output 7 2 General Messages The following messages may appear when using the F requen cy Analysis module 7 2 2238 Mediator Br el amp Kjeer Frequency Analysis Software BZ 7123 User Manual Chapter 7 Appendix General Messages Message Measurement will be reset Continue Spectrum incomplete Save anyway Measurement incomplete Save completed scans Occurs When one or more scans remain in the Averaged Spectrum and you try to 1 Press the reset key 2 Change the range setting 3 Change one of the weighting parameters 4 Change the Dwell Time or Tolerance val ues in the Meas Con trol Window 5 Change the Correc
47. u l 10 Error Messages ee 7 4 LxYmax 1 9 1 10 IXY MUR evertere 1 9 1 10 F M Fast slow time constants ssss 1 6 File Marks overload underrange 5 3 Manager secs 2 2 5 4 5 5 Measurement store 5 3 Control Window sss sese eene 3 4 5 3 Filter set 3 3 d ta 2 2 Fixed dwell time 3 5 parameters sss 1 9 6 2 8 5 Fluctuating signals eee 1 5 range enii 2 3 Frequency Result key 2 3 analysis 1 4 result windows 2 3 4 2 bands 1 4 settings 3 2 bands selecting 5 6 eee 0352 range limits 3 3 Set up menu e enki PUE e o as ighting broadband 3 3 e weighting broadband Measuring ranges 6 2 Menu items selecting 2 3 G Microphone type 5 2 General Multiple scans storing sss eee eee eee 5 4 MESSAGES T m 7 2 parameters vevd siu a cn ves 1 10 N NE nuo niae ie one 5 3 I Non stationary signals 3 4 Input Output Normal distributed random signal 1 6 TUNCE ON nra ce errem eere 3 6 Number of scans eene 3 4 4 3 9 2 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ7123 User Manual I ndex Oo EP 8 4 Octave and 1 3 octave band filters 6 3 Overload 8 4 Octave bandwidth 43 3 Scan Number 8 4 Optimized dwell time 3 5 Start Date 8
48. ut e Trigger Output DC Output supplies a DC output signal equivalent to the AC output signal Full scale indication corresponds to 4 0V DC 50 mV dB Trigger Input Starts a measurement when an external trigger voltage is applied The trigger level is 2V refer to 2238 Mediator Br el amp Kj r Frequency Analysis Software BZ 7123 User Manual Chapter 3 Measurement Set up Menu Measurement Set up Menu Specifications A trigger is ignored if Mediator is not paused and displays one of the Measurement Windows Trigger Output supplies a status voltage that is high 24V DC when a measurement is proceeding or low OV when the instrument is paused The Trigger Out signal can be used to start stop external equipment such as tape and level recorders BB1128 11 2238 Mediator 3 7 Frequency Analysis Software BZ 7123 User Manual 2238 Mediator Frequency Analysis Software BZ7123 User Manual Br el amp Kj r Chapter 4 Measuring 4 1 Measurement Result Windows 4 2 Working and Averaged Spectrum Windows 4 2 Broadband Measurement Window sess 4 4 Selecting Spectrum Parameter for Display 4 4 Using the Spectrum Cursor eee 4 5 lee n Lee 4 nce dete cerit citis Derek tects 4 5 Pausing Interrupting a Measurement 4 5 INSTANTANEOUS Value eee eee eee eee eee 4 6 42 Era
49. ved The only exception is when the first scan is not finished In this case it is possible to save the finished frequency bands after a warning that the scan is incomplete The saved frequency bands are also shown in the Averaged Spectrum After saving an incomplete scan the measurement can be continued Display Layout The two spectrum windows are fairly similar The upper pa rameter line Time Left in the Working Spectrum Window shows the total remaining measurement time In the Aver aged Spectrum window this field is replaced with a Scan No line which shows the current total number of scans Note Measurement times higher than 1000hours are dis played as in the Time Left fields in the Broad band Measurement and Working Spectrum Windows BB1128 11 2238 Mediator 4 3 Frequency Analysis Software BZ 7123 User Manual Chapter 4 Measuring Measurement Result Windows 4 1 2 4 1 3 The second parameter line in both windows show the current spectrum parameter and the frequency measurement value which the cursor points at or which is being measured Broadband Measurement Window The Broadband Measurement Window is similar to the M eas urement Window in the Basic module In the four parameter fields you can select between the parameters available in the Frequency Analysis module e Lxvinst Lxyp Lxeg LxvMax LxvMin Overload96 Under range Time Left Start Date Start Time Elapsed Time Time Scan No
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