Casella | HB3340-02 | Operator`s manual | Casella HB3340-02 Operator`s manual

CEL-600 SERIES SOUND LEVEL METER
HB3340-02
OPERATOR’S MANUAL
CASELLA CEL
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Wolseley Road,
Kempston,
Bedford,
MK42 7JY, U.K.
Phone: +44 (0) 1234 844 100
Fax: +44 (0) 1234 841 490
E-mail: info@casellacel.com
Web: www.casellacel.com
August 2009
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TABLE OF CONTENTS
SECTION
TITLE
PAGE
1
Introduction
4
2
Instrument Features
4
3
Operation
7
3A
Switch On
7
3B
Setting Screens
8
3C
Date & Time Screens
11
3D
Set Language
12
3E
Set Backlight
12
3F
Set Run Duration
14
3G
Calibration ref Level
15
3H
View Memory Results
16
3I
Delete Memory results
17
3J
Run Screens
18
3K
Instrument Calibration
19
3L
Extracting Data
20
3M
System Tools
21
4
Storage
21
5
Low and High Level Sound
21
6
Specifications
23
7
Servicing and Warranty Arrangements
28
8
Appendix A - Glossary of Terms
29
9
Appendix B - Additional information
31
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1. INTRODUCTION
CEL-600 Series is a range of Sound Level Meters been designed to meet the
demands of worldwide industrial health and safety professionals as well as general
noise measurement applications. The instrument encompasses functionality from
basic sound level measurement to integrating and real-time octave band analysis.
The CEL-600 instrument is based on the very latest digital signal processing
technology and has a crisp, vibrant colour TFT LCD display. This precision
instrument is designed to bring your noise measurements up to date giving confident
and reliable performance fully compliant with international standards.
Data is stored in a .csv format, compliant with MS Office applications, and through
the USB connection, the .csv files can be copied to a PC without the need for any
propriety software packages.
Back to Index
2. INSTRUMENT FEATURES
The CEL-62X Sound Level Meter comprises of several variants, where the ‘X’
represents a number which determines the model variant and subsequent features.
Subsequent letters denote the frequency analysis capability, ‘A’ for broadband, ‘B’ for
1/1 octave band and ‘C’ for 1/3 octave, e.g CEL-620C.
CEL-620
An integrating meter providing A, C, and Z frequency weightings, Fast Slow and
Impulse time weightings with cumulative storage and PC connectivity functions. A
single measurement range of 140dB RMS is standard. Simultaneous LAeq and LCeq
values are measured for use in the HML selection of hearing protection method. Lavg
is available with a selectable threshold. This model is available in Class 1 or Class 2
accuracy standards.
CEL-621
Additional parameters are added for the measurement of environmental noise.
Statistical parameters (Ln%) are available and can be altered to suit specific
environmental legislation.
Frequency Analysis
Models providing ‘Integrating’ functionality combined with addition of 1/1 Octave
bands (B model) or both 1/1 Octave and 1/3 Octave bands (C model) analysis. This
instrument is designed to satisfy the demands of all industrial noise at work
applications. Octave results may be displayed graphically or in numerical form and
can be A, C or Z frequency weighted. Advanced DSP processing provides fast
parallel processing of Octave results from 16Hz to 16kHz, or 1/3 Octave results from
12.5Hz to 20kHz. This model is available in Class 1 or Class 2.
DESCRIPTION (Refer to Figure 1)
The CEL-62X has a compact, ergonomic and robust ‘rubber grip’ case design that
sits the instrument comfortably in the hand when not mounted on a tripod. The ½”
microphone (under windshield 1) can be removed from the fixed preamplifier (2). The
windshleid (1) should be used to cover and protect the microphone at all times.
When the instrument is switched ON (3) it will run through its own software
initialisation and then default to a Stop mode (Red Bar) screen.
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To navigate within a screen use the Cursor Keys (6). Not all the screens have
navigable fields on the display. To navigate from one screen to another, use the Soft
Keys (5). To start a ‘run’ (measurement), press the Start key (7); to stop the run
press the same key again.
The instrument has a single measurement range to 140dB (RMS) and 143.3dB (C)
peak. No range adjustment is needed which greatly simplifies operation.
The CEL-62X can be ‘explored’ just like a USB memory device and the data files of
the individual measurements are saved in a .CSV (Comma Separated Variable)
format that is compatible with MS Office applications. This means that no software
needs to be installed onto a PC to retrieve the data.
The CEL-62X measures all the required parameters simultaneously with the required
frequency and time weighting.
1 – Windshield (covering removable microphone), 2 – Fixed Pre-amplifier,
3 – ON/OFF Key, 4 – Display, 5 – Soft Keys, 6 – Navigation Cursor Keys,
7 – Run/Stop Key.
Figure 1 CEL-62X Series
Back to Index
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BATTERY INSTALLATION (Refer to Figure 2)
CAUTION: The batteries can be zinc carbon, alkaline or rechargeable. Do not
mix battery types.
The CEL-62X Instrument requires three AA batteries. Remove the battery
compartment cover. Check correct polarity. Fit the batteries. Refit the battery cover.
Press and release the ON/OFF Key. Check the battery condition symbol shows the
battery has a good charge.
Note: For long term tests, where the batteries may become exhausted, use a 12VDC
supply to power the CEL-62X. The 12VDC can be plugged in at any time and will be
automatically used instead of the batteries. When downloading data to a PC the
CEL-62X can be powered by the USB connection. The 12VDC or USB connection
will not re-charge batteries. With 12VDC or USB connected the battery condition
symbol will show full charge and not the actual condition of any installed batteries.
To extend battery life, if the CEL-62X is not making a measurement run and there are
no key presses, the instrument will automatically turn off after a period of 5 minutes.
This auto power off facility is disabled when the CEL-62X is powered from 12VDC or
USB. The auto power off facility is independent of the backlight time settings – see
paragraph E – Set Backlight below.
Figure 2 Battery Charge Indicator and Battery Installation.
Back to Index
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3. OPERATION
A. SWITCH ON the CEL-62X INSTRUMENT (Refer to Figure 3)
Press the red power key to switch the instrument on (see Figure 1). The instrument
software screens have been designed with colour coded top and bottom bars to
enable the user to know at a glance which part of the firmware (operating system) is
currently being accessed.
Colour coding is as follows:
RED – Stop screens. These screens are displayed when the instrument has
completed initialisation after power-up, as well as prior to taking a measurement run.
BLUE – Setting screens. These screens are used to set up the instrument correctly
and includes settings such as date and time, language and backlight.
LIGHT BLUE – Memory Results screens. This is where the results from
measurement runs are viewed.
GREEN – Run screens. These screens show a measurement run is in progress.
Measured values are stored in the Memory Results.
YELLOW – Calibration screen. This screen is automatically displayed upon
application of a 1kHz Acoustic Calibrator. This is where the instrument is calibrated
prior to a run.
This is a precision instrument and should be calibrated before use to ensure
accurate measurements.
Also care should be taken that the operator does not unduly affect the sound field.
Ideally the instrument should be mounted on a sturdy tripod with the microphone
perpendicular to the source of the sound to be measured – the operator should be as
far behind the instrument as possible. If the instrument is to be hand held, then the
arm of the operator should be stretched out as far as possible to minimise reflections
from the operator’s body. Refer to Appendix B for the affects of the instrument on the
sound field.
CEL- 62XA – When the instrument is powered up, the initialisation screen will be
displayed first, followed by the Graph screen in the STOP mode (red bars). Press the
MENU Key (A) to access the MENU screen.
CEL- 62XB or CEL-62XC – When the instrument is powered up, the initialisation
screen will be displayed first, followed by the Octave (or 1/3 Octave on C models)
screen in the STOP mode (red bars). Press VIEW to see the Graph screen. Press
the MENU Key (A) to access the MENU screen.
The instrument is ready to make measurement immediately after the initialisation
screen has been displayed (approximately 10 seconds after switch ON).
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Figure 3 Switch ON the CEL-62X
B. SETTINGS SCREENS (Refer to Figure 4)
Note: Press EXIT (A) at any time to go back to the previous screen.
SETTINGS
The Settings menu allows configuration of instrument setup, time/date, language,
backlight, run duration timer and calibration level.
Use Cursors (C) to select the Settings icon (1) and press Select (B).
CHANGING FROM 1/1 OCTAVE TO 1/3 OCTAVE
CEL-62XC models have both 1/1 octave and 1/3 octave functionality. In order to
change between 1/1 octave and 1/3 octave Use cursors (C) to select the Octave icon
(3) and press Select (B). Use cursors (C) to select either 1/1 octave or 1/3 octave
and press Select (B) to exit.
Note: This option is only available on 1/3 octave CEL-62XC models.
62X SETUP
This menu allows selection of the parameters to be viewed during a measurement
run. Note that regardless of the measurement view selected, all parameters will be
stored simultaneously and can be viewed via a PC. Use cursors (C) to highlight 600
SETUP icon and press (B).
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MEASUREMENT VIEW.
Predefined views are available to satisfy measurements for international workplace
noise legislation. Use the cursor keys (C) to select the required view and press (B) to
activate the measurement view. The Measurement View with the word ACTIVE next
to it will be used for measurement runs. To view the details press View (B).
On CEL-621 units, two fixed environmental views are available which provide
additional statistical parameters (Ln%) and parameters unique to workplace noise are
removed.
USER 1 AND 2 SETTINGS.
Two customiseable views are available in which measurement weightings and
paramaters can be set. When one of these views is Active by pressing the (B) key,
press (B) again to edit the view. Left right cursor keys are used to make changes
and up/down cursor keys are used to move to the next field. On this screen you can
define the following:
RESPONSE (Random/Freefield)
Random microphone response is typically used to conform to US legislation for
workplace noise whereas Freefield is used throughout the EU.
LAVG THRESHOLD (70-90dB)
The threshold is used for the calculation of LAVG, which is the level at which all noise
below is ignored. Note with threshold set to zero the threshold is off.
OCTAVE WEIGHTING (A, C or Z)
The frequency weighting used to display 1/1 or 1/3 octave band results. Note that
regardless of the settings selected, Z weighted measurements are stored so the data
can be post-processed on a PC to C or A weighting.
OCTAVE TIME CONST (F or S).
The time weighting used to display 1/1 or 1/3 octave band results. Regardless of the
selection, both time weightings are stored simultaneously for LMAX results. Time
weightings of Fast (F) or Slow (S) do not apply to Leq measurements.
Press (D) to restore defaults. Press (B) to open the Functions screens for the
selected ‘User 1 View’.
Figure 4 Setting Options (Sheet 1)
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USER 1 AND 2 MEASUREMENT PARAMETERS
The Functions screens allow the Operator to select up to nine functions for the
measurement ’run’. A counter replaces the battery level indicator at the foot of the
screen. The counter displays the number of parameters selected.
Press the Functions key (B) and use the cursor keys (C) to navigate
up/down/left/right.
The first screen shows Sound Pressure Level (SPL) and Leq values. The parameters
displayed during a measurement run are highlighted in green.
The Main SPL value is highlighted in red, which is the SPL value shown in Stop and
Run modes. To select the Main value press and hold the Run/Stop key (D) until the
parameter is highlighted in red.
Other parameters can be added. Navigate to the appropriate parameter that is to be
added. A rectangle indicates the selected parameter. Press the Run/Stop key (D) to
select the parameter. The parameter is highlighted green to show it is selected.
Repeat for any subsequent parameters that need to be selected and access the
additional screen by pressing the More key (B). Press Back (A) to exit and any
changes will be automatically saved.
The CEL-621 will have an additional screen to adjust the stored statistical data.
Within these setups, Ln% values can be switched on and off as required and one of
the Ln values can be varied to any percentage between 0.1 and 99.9%.
Figure 4 Settings Options (Sheet 2)
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C. DATE AND TIME SCREENS (Refer to Figure 5)
SETTINGS
From the Menu select the Settings icon (1) and press (B) to select.
SET CLOCK
Use the cursors (C) to select the Set Clock icon and press (B) to select.
SET TIME
The screen will be displayed with the Time highlighted. To set the time press Edit (B).
The hour will be highlighted. Adjust the hour setting use the Up/Down cursors. Press
the cursor key (C) to highlight the minutes. Adjust the minutes setting use the
Up/Down keys. Press the cursor key (C) to highlight to the seconds. Adjust the
seconds setting use the Up/Down keys. When the correct time has been set, press
Save (B).
SET DATE
Press Cursor Key (C) to move the highlight to the date. Press Edit (B) The day will be
highlighted. Change the day setting use the Up/Down keys. Press the cursor key (C)
to highlight the month. Adjust the month setting use the Up/Down keys. Press the
cursor key (C) to highlight to the year. Change the year setting use the Up/Down
keys. When the correct time has been set, press Save (B).
CLOCK SET. The time and date is now set. Press EXIT to go back to the Set Clock
screen.
Figure 5 Set Date and Time
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D. SET LANGUAGE (Refer to Figure 6)
LANGUAGE
From the Menu select Settings (1). Use the cursor keys (C) to navigate to the World
icon (2). Press Select (B).
Use cursors (C) to select the desired language and press (B) to select. Press Exit
(A) when finished.
Figure 6 Set Language
E. SET BACKLIGHT (Refer to Figure 7)
BACKLIGHT
From the Menu select Settings (1). Use the cursor keys (C) to navigate to the
Backlight icon (2). Press Select (B).
Figure 7 Set Backlight (Sheet 1)
ACTIVATION. The screen will be displayed with the Activation symbol highlighted. To
set the Activation mode press Edit (B). Use the cursor keys (C) to toggle between the
following backlight modes:
KEYPRESS- The backlight stays on for a set Duration following any key press.
ON- Backlight remains on continuously. If the ON option is selected the Duration
setting will be disabled.
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DURATION. If the Activation mode is set to Keypress, the duration the backlight
remains on can be set. Press cursor key (C) to navigate to highlight Duration. To set
the Duration press Edit (B). The Duration field will be highlighted with the Minutes
enabled. To change the minutes use the Up/Down keys (C). Use cursor keys (C) to
highlight the seconds. To change the seconds use the Up/Down cursors (C). When
the Activation mode has been set, press Save (B).
Figure 7 Set Backlight (Sheet 2)
BRIGHTNESS. The backlight brightness affects the battery life. For improved battery
performance use the lowest brightness level suitable for your environment.
Press cursor key (C) to navigate to highlight Brightness. To set the Brightness press
Edit (B). The Brightness symbol will be highlighted. To adjust the brightness use the
cursor keys (C). When the Brightness mode has been set, press Save (B).
Press EXIT (A) to go back to the Settings screen.
Figure 7 Set Backlight (Sheet 3)
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F. SET RUN DURATION (Refer to Figure 8)
RUN DURATION
The Duration timer allows measurements runs to be performed over a specified time.
At the end of this time the measurement will automatically be stopped. From the
Menu select Settings (1). Use the cursor keys (C) to navigate to the Run Duration
icon (2). Press Select (B).
DURATION TIMER
Press (B) to edit the Duration timer to either On or Off and use cursors (C) to change
the selection. Press Save (B) to continue.
Figure 8 Run Duration (Sheet 1)
DURATION. Press cursor key (C) to navigate to the Duration field. Press Edit (B) to
change the Duration time. Use the Up/Down cursors (C) to make changes as
required. Range of duration/integration time is 00:00:01 to 24:00:00 in 1 second
steps.
Press Save (B) to save the changes. Press Exit (A) Settings screen.
Figure 8 Run Duration (Sheet 2)
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G. CAL. REF. LEVEL (Refer to Figure 9)
Note: For Instrument Calibration refer to Section K – Calibration Screens.
For free field and microphone corrections to the calibrator level refer to “Sound
Calibrators – Level Corrections” in Appendix B.
CAL. REF. LEVEL
The Calibration Reference Level is used to set the instrument’s calibration level to
the exact level of your calibrator plus any other required corrections. Calibration
levels can be set from 93-95dB or 113-115dB. A 1kHz calibrator must be used.
From the Menu select Settings (1), use the cursor keys (C) to navigate to the Cal.
Ref Level icon (2). Press Select (B).
The Calibration Reference Level (Cal. Ref. Level) screen will open with the last level
used for calibration. Press Edit (B) to alter the level.
The first digit can be selected 0 or 1 only, other digits can be 0-9. Use cursor keys
(C) to make changes as required and press (B) to save changes.
Press Exit (A) to go back to the Settings screen.
Figure 9 Calibration Reference Level
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H. VIEW MEMORY RESULTS (Refer to Figure 10)
This is where the results from completed measurements are stored. The Memory
Results are stored in a chronological order, with the latest measurement at the top of
the list.
MEMORY RESULTS
From the Menu screen, use the cursor keys to select the Memory Results icon (1).
Press Select (B) to access the memory.
Use the Up/Down cursors (C) to navigate the listed results. When a Memory Result
has been selected, press Select (B) to access the measurement.
This screen gives the operator the choice to view the selected memory result, or to
delete it. Use the left/right cursor keys (C) to select View and press Select (B).
The Results screen displays an overview of measurement data for the selected run.
This is read only. To see the specific results, press View (B).
Figure 10 View Memory Results (Sheet 1)
The Octave values (CEL-62XB and C models only) saved in the Memory Result are
displayed in a graphical format. Use cursor keys (C) to move the cursor (1) across
the graph. Each graph bar represents an octave band measured in Hz or KHz.
Use the up/down cursors keys (C) to toggle between parameters such as LMAX and
LAEQ (2).
To view the numerical results (CEL-62XB and C models only), press View (B).
On CEL-62XC models, use the up/down cursors (C) when viewing numerical results
to alter the frequencies viewed.
Press EXIT (A) to leave the Memory Results or VIEW (B) to cycle the Memory
Results screens again.
Note: On CEL-62XC models either 1/1 octave values or 1/3 octave values will be
displayed dependent on the setup at the time of measurement.
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Figure 10 View Memory Results (Sheet 2)
I. DELETE MEMORY RESULTS (Refer to Figure 11)
From the chronological list of measurement runs, use the Up/Down cursors (C) to
navigate the listed results. When a Memory Result has been selected, press Select
(B) to go to the next screen.
This screen gives the operator the choice to view the selected memory result, or to
delete it. Select Delete and press Select (B).
This screen asks the operator to either delete only the current run or to delete all the
measurement runs within the memory. Use the cursors (C) to make the required
selection and press (B) to Select. The next screen asks for final confirmation to
permanently delete the Memory Result. Press (A) to confirm. The Memory Result will
be permanently deleted. If not sure, press (B) to go back the Memory Results list.
Figure 11 Delete Memory Result
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J. RUN SCREENS (Refer to Figure 12)
The Instrument has four Run screens: The Main screen, the Graph screen, the
Octaves screens and the Octaves Values screen, the last two of which are only
available on the CEL-62XB and CEL-62XC.
Switch ON the instrument as detailed in Figure 3.
CEL-62XA – Press the RUN/STOP Key (D) to go to the Graph screen.
CEL-62XB and CEL-62XC– OCTAVE screen. Press the RUN/STOP Key (D) to go to
the Octaves screen (or 1/3 Octave on CEL-62XC model).
All CEL-62X Models – The “Play” symbol is displayed in the top left hand corner of
the screen. The “Pause” symbol is in the bottom left hand corner of the screen. The
left hand Soft Key (A) is the PAUSE/RUN feature. When Pause is selected,
‘PAUSED!’ will be displayed on the screen. The incremental run number and duration
are displayed in the top right hand corner of the screen. If the Run Duration Timer is
set, a ‘stopwatch’ icon will appear next to the countdown timer. The Run Duration
timer is enabled and disabled in SETTINGS (Refer to Figure 8). If the Run Duration is
not set, the digital timer will count up until the run is stopped manually (by pressing
D).
Figure 12 Run Screens
CEL-62XA (Refer to Figure 13). The broadband values can be viewed as a
bargraph on the Main screen, or as a graphical time history on the Graph screen.
Pressing View key (B) toggles between Graph and Main screens.
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Figure 13 CEL-62XA Run Screens
CEL-62XB & CEL-62XC (Refer to Figure 14).
The CEL-62XB and CEL-62XC provides two additional octave screens shown in
Figure 14. Use the View key (B) to toggle the four available screens. Use the left/right
cursor keys (C) to move across the frequency bands (1) when in graphical view. Use
up/down cursor keys (C) to toggle between LMAX and LEQ parameters (2).
Each graph bar represents an octave band measured in Hz or kHz. To view a table
of the octave values, press View (B).
On CEL-62XC models, use the up/down cursors (C) when viewing numerical table to
alter the 1/3 octave frequencies viewed.
Figure 14 CEL-62XB & C Main Run Screens
K. INSTRUMENT CALIBRATION (Refer to Figure 15)
Note: The Instrument must be at a STOP screen before the Acoustic Calibrator is
fitted.
For calibrator reference level adjustment refer to Section G.
Calibrations should be performed before and after measurements. Fit the acoustic
calibrator over the removable microphone and push it home. Switch the calibrator on
using ON/OFF Key (1). The Instrument detects the signal and automatically activates
the calibration screen (yellow bars). Press (B) to begin calibration. The instrument will
be calibrated and the word PASSED displayed. A ‘calibration change’ value is shown
at the bottom of the screen. This identifies the change since the previous calibration.
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Remove the acoustic calibrator. Press EXIT (A) to go back to the Stop screen. Press
and hold the acoustic calibrator ON/OFF Key to switch the calibrator off.
Figure 15 Instrument Calibration
L. EXTRACTING DATA (Refer to Figure 16)
Each measurement run is stored as a file within the CEL-62X in a .CSV format. This
format will automatically open with MS EXCEL or similar office applications. The files
are named consecutively from 1 to 100, so the first run will be named R001.CSV. All
measurement parameters are contained within these files, regardless of the
displayed parameters selected within the instrument setup.
The CEL-62X acts as a removable storage device when connected to a PC by the
CMC51 cable. See Figure 18 for the location of the USB connection on the CEL-600
Series. Once connected, the PC will automatically detect the instrument is
connected and within a few seconds have installed the necessary drivers. An
Explorer window will open on the PC to show the files on the instrument. Simply
copy the files to your PC as required.
Figure 16 Measurement Data Files
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M. SYSTEM TOOLS (Refer to Figure 17)
The system tools menu can be accessed from the startup screen by pressing the
left/right cursor keys (C) together. Note that these functions need not be used within
general operation and stored results will be lost if incorrectly used. Their primary
function is for calibration laboratories or diagnostic purposes. Three options are
available:
‘Recover USB Disk Files’ copies files stored in the backup E2 memory to the USB
disk.
‘Set USB Disk R/W’ allows the mass storage device to have data written to it. Note
that this is primarily used for testing purposes.
‘Format All Memory’ will format the USB memory. CAUTION: All measurement data
will be lost!
Use cursor keys (C) to highlight the required option and press (B) to select. When
selected a final confirmation will be shown, press (A) to confirm or (B) to cancel.
Once finished, press (A) to exit.
Figure 17 System Tools
4. STORAGE
Keep the Instrument and the associated equipment in its padded case at all times
when not in use. Keep the Instrument dry, in a dust free environment, and away from
heat generating and ozone generating sources. If the Instrument is not going to be
used for a week or longer, remove the batteries from the battery compartments.
Back to Index
5. LOW AND HIGH SOUND LEVELS
Low Level Sounds.
Providing the sound level being measured is within the linearity range (refer to
Appendix B paragraph “e - Linear operating range”), self generated noise and
linearity corrections can be ignored.
When the measured RMS sound level is below the linearity range and 3 dB above
the self generated noise (refer to Appendix B paragraph “h - Self generated noise), it
is possible to correct the measured level by the following formula:
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Note: As the CEL62X is a single range instrument capable of reading to zero dB, and
the only non linearity error will be due to self generated noise, then there is no underrange indicator.
Lact = 10log(10
Where
(Lms)/10
– 10
(Lsg)/10
)
Lact = Actual corrected sound level
Lms = Measured sound level
Lsg = Self generated noise level
High Level Sound (Overload).
When a sound level is detected that is above the linear operating range, the display
will indicate overload by a red upward facing arrow at the top of the display.
If the CEL-62X is not completing a measurement run then the overload indication will
automatically reset approximately 2 seconds after the sound level is reduced to
below overload.
If the CEL-62X is completing a measurement run then the overload indication will
remain, even if the overload sound level is reduced, until the measurement run is
terminated manually or by the timer. If the data collected during the run is viewed on
the CEL-62X, or downloaded to a PC, then an overload will be reported in the data.
Refer to sections F,H & J to set run durations, memory results and run screens.
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6. SPECIFICATIONS
GENERAL
The CEL-62X provides SPL, Integrating and Octave band noise measurement
compliant with the following international standards:IEC 61672-1 2002-5 (Electro-Acoustics – Sound Level Meters) Group ‘X’
instruments. Performance of Class 1 or 2 as relevant to instrument model.
IEC 60651: 1979, IEC 60804: 2000, ANSI S1.4: 1983, ANSI S1
1/1 Octave and 1/3 Octave Filters comply with EN61260: 1996, Class 0 and ANSI
S1.11 1986, Order-3 Type 0C.
MEASUREMENT RANGE
Single measurement range up to 140.2dB(A) RMS and 143.3dB (C) Peak. Linearity
range from 10dB above noise floor.
RMS FREQUENCY WEIGHTINGS
A, C and Z filter weightings, satisfying IEC 61672-1: 2002 Class 1.
OCTAVE MEASUREMENT
Real-time 11 bands with centre frequencies from 16Hz to 16KHz. Displayed
Spectrum may be pre-weighted with A, C or Z.
Z weighted octaves only are stored to be post weighted in dB36 software.
PEAK MEASUREMENT
A, C and Z weighted from 65.0 to 143.3dB
RMS DETECTOR
Digitally derived True root-mean-square detection (RMS), 0.1dB display resolution.
NOISE FLOOR
Total inherent Noise including microphone thermal noise @20°C - <22dB(A) Class
1, <30dB(A) Class 2.
Electrical Noise floor <20dB(A).
FREQUENCY RESPONSE
6Hz to 20kHz (upper and lower 3dB frequencies). Digital Sampling rate 67.2KHz
Overall Class 1 and 2 frequency response compliant with IEC 61672-1: (2002)
TIME WEIGHTINGS
Fast, Slow and Impulsive according to IEC 61672-1: (2002).
CORRECTION FILTERS
Built in correction filter for random incidence sound pressure fields.
REFERENCE DIRECTION
For free field measurements the reference direction is perpendicular to the
microphone diaphragm.
REFERENCE CONDITIONS
23oC air temperature, 50% Relative Humidity,
101.325kPa atmospheric pressure.
Nominal reference level = 114.0dB at 1kHz
Casella CEL Limited
23
OPERATING ENVIRONMENTAL CONDITIONS
Humidity: 5 to 90%RH in the absence of condensation.
Temperature range: -10 to +50oC (Class 1), 0 to +40oC (Class 2)
Pressure: 65 to 108kPa
EFFECT OF TEMPERATURE
Electrical stability of instrument < ±0.2 dB over the range -10 to +50oC
EFFECTS OF HUMIDITY
Less than ±0.5dB over the range 25 to 90% relative humidity (non-condensing),
relative to the value at reference conditions.
STORAGE ENVIRONMENTAL CONDITIONS
Humidity: 0 to 90%RH in the absence of condensation.
Temperature: -20 to +60oC.
Pressure: 65 to 108kPa
MICROPHONE
Class 2: CEL-252 ½” Class 2, 30mV/Pa pre-polarised back electret.
Class 1: CEL-251 ½” Class 1, 50mV/Pa pre-polarised back electret.
Note: Instrument has fixed preamp so class is determined by microphone only.
CALIBRATION
Auto calibration by application of 1KHz calibrator, nominal level 114 or 94dB +/-1dB.
Auto calibrated to a user specified reference level with recording of date, time and
offset.
POWER SUPPLY
External DC: 9 to 14V DC at typically 170mA. 2.1mm Power Connector.
Batteries: 3x AA Alkaline or rechargeable cells
Battery Life: Typically >8 hours in Broadband mode with backlight continuously on
low intensity. High backlight setting will have a detrimental affect on battery life.
12 hours measuring with backlight off.
INTERNAL CLOCK:
Date and time accuracy better than 2 sec per day.
LANGUAGES:
English (default), Spanish, French, German, Italian, Portuguese, Chinese, and
Brazilian Portuguese.
ELECTROMAGNETIC COMPATIBILITY
Instrumentation is designed and tested to comply with the following EMC and ESD
Standards:
IEC 61000-4-2 Testing and Measuring Techniques - Electrostatic discharge immunity
tests.
IEC 61000-4-3 Electromagnetic compatibility (EMC) - Radiated electromagnetic field
tests.
IEC 61000-4-6 Electromagnetic compatibility (EMC) - Immunity to conducted
disturbances induced by radio frequency fields. Tested at 10V/m or greater.
EFFECTS OF AC POWER FREQUENCY FIELDS
Less than ±0.5dB change from 74dBA 925Hz reference level when subjected to
160A/m AC magnetic field at 50 and 60Hz.
24
Casella CEL Limited
TRIPOD MOUNTING
Socket to mount on standard 1/4" (Whitworth) camera tripod thread.
DISPLAY
320x240 Transmissive Colour TFT. Update period 0.5 seconds.
MEMORY
Micro SD 1GB Non-volatile internal.
CONNECTIVITY (Refer to Figure 18)
USB: Mini B to download to dB36 software or to explore via Windows Explorer to
obtain .CSV file.
AC OUTPUT: Via 2.5mm stereo audio jack (Barrel ground, Tip AC output) provided
for remote monitoring, DAT tape / PC wav file recording or headphone applications.
Approx 0.4V RMS full scale output corresponding to 96dB. Output impedance approx
2.2kΩ. Load impedance should be as high as possible, and for connection cable in
excess of 0.5 metres coaxial cable should be used. It is recommended that cable
length should be kept to below 10 metres.
The AC output corresponds to the Z weighted response of the sound level meter.
DC OUTPUT: Via 2.5mm stereo audio jack (Barrel ground, Ring DC output) provided
for chart recorders, loggers etc. (note: some offset and scaling will be required on the
measuring system for accurate measurements).
Approx 1.4V DC full scale output corresponding to 140dB. Output impedance approx
2.2kΩ. Load impedance should be as high as possible.
The DC output corresponds to the A weighted, Fast time response of the sound level
meter.
Note: DC power input ground should be kept isolated from any signal ground.
Power
Socket
Audio Jack
Socket
USB
Socket
Figure 18 Connectivity
PHYSICAL CHARACTERISTICS
Dimensions: (WxHxD) 71.5x 230.0x 31.0mm for instrument including microphone
and preamplifier.
Weight: <310g including batteries.
Casella CEL Limited
25
AVAILABLE PARAMETERS
Broadband
DISPLAYED FUNCTIONS
SLM RESPONSE
RMS Weight Time Weight
(w)
(t)
Z
C A F
S
I
NOTES
Function
Format
Displayed
Example
SPL
L(wt)
LAF
√
√
√
√
√
SPLmax
L(wt)mx
LZSMAX
√
√
√
√
√
SPLmin
L(wt)mn
LZSMIN
√
√
√
√
√
LWEQ
LAEQ,
√
√
√
NA NA
Lpeak
L(w)Pk
LCPEAK
√
√
√
NA NA
LIEQ
integrating
L(w)IEQ
LAIEQ
NA
NA
√
NA NA
LAEQ T80
LAEQ T80
LAEQ T80
NA
NA
√
NA NA
LAEQ with
NA Threshold and
Q=3 (ACGIH)
L(w)E
LAE
NA
NA
√
NA NA
NA
LTM3
LTM3
LTM3
NA
NA
√
√
NA
NA
LTM5
LTM5
LTM5
NA
NA
√
√
NA
NA
LEQ
integrating
LAE
*LAVG
integrating
L(w)AVG
LAVG,
NA
NA
√
NA
HML
LC-LA
LC-LA
NA
√
√
NA NA
26
√
Measures single
W and T
weighting
Lmx adopts
frequency
√
weighting as
selected for SPL
Lmn adopts
frequency
√
weighting as
selected for SPL
SPL value
changes to LEQ
during a
NA measurement
run.
(Simultaneous
C&A)
A peak only
NA available on user
setups
√
√
Impulsive LEQ.
LAVG based on
selectable
threshold 70NA
90dB, Q5 or Q4
and Slow
weighting.
LEQ only, Lavg not
NA
required
Casella CEL Limited
Additional 1/1 Octave & 1/3 Octave Band Functions for CEL-62XB &
CEL-62XC
DISPLAYED FUNCTIONS
Function
SLM RESPONSE
RMS Weight Time Weighting
(w)
(t)
Z C A
F
S
I
Displayed
Format Example
SPL
L(wt)
LAF
√
√
√
√
√
NA
SPLmax
L(wt)mx
LZSMAX
√
√
√
√
√
NA
LEQ
integrating
LWEQ
LAEQ,
√
√
√
NA
NA
NA
NOTES
Only Z weighting
is saved
Only Z weighting
is saved
DEFAULT SETUP MATRIX
ISO
OSHA
DOD
ACGIH
USER
1
USER
2
3
5
4
3
3
5
0
80
80
80
0
Broadband
Parameters
LAF
LAeq
LCeq
LC-Aeq
LAFmax
LCpeak
LAS
Lavg
LASmax
LZpeak
LC-Aeq
LAS
Lavg
LASmax
LZpeak
LC-Aeq
LAS
LAeq (T80)
LASmax
LZpeak
LC-Aeq
Octaveband
Parameters
LAF
LAeq
LAFmax
LAS
LAeq
LASmax
LAS
LAeq
LASmax
LAS
LAeq
LASmax
SETUP
Exchange
Rate
Threshold
Environmental
1
3
Environmental
2
3
90
0
0
LAF
LAeq
LCeq
LC-Aeq
LAFmax
LCpeak
LAFmin
LAF10
LAF50
LAF90
LAF95
LAF99*
LAS
Lavg
LCeq
LASmax
LZpeak
LC-Aeq
LASmin
LAF10
LAF50
LAF90
LAF95
LAF99*
LAF
LAeq
LAFmax
LZpeak
LAFmin
LAF10
LAF90
LAF
LAeq
LAFmax
LZpeak
LAFmin
LAF10
LAF50
LAF90
LAF95
LAF99
LAF
LAeq
LAFmax
LAF10
LAF50
LAF90
LAF95
LAF99*
LAS
LAeq
LASmax
LAF10
LAF50
LAF90
LAF95
LAF99*
LAF
LAeq
LAFmax
LAF10
LAF90
LAF
LAeq
LAFmax
LAF10
LAF50
LAF90
LAF95
LAF99
*
4 Ln% values are fixed, 1 is variable in User 1 and User 2 setups.
Back to Index
Casella CEL Limited
27
7. SERVICING AND WARRANTY ARRANGEMENTS
To ensure conformity with the specification, this instrument is thoroughly inspected
and it’s accuracy verified prior to dispatch. All technical information is filed under the
instrument serial number, which should be quoted in any correspondence. The
manufacturer undertakes to rectify any defect in the instrument directly attributable to
faulty design or assembly and which becomes apparent during the warranty period.
In order to take advantage of this warranty, the instrument must be returned, carriage
paid, to the manufacturer’s factory or accredited agent, where necessary repairs will
be carried out.
The warranty period runs for 24 months from the date of receipt of goods, with
exceptions on certain specialised components supplied by other manufacturers that
may be warranted for shorter or longer periods by their actual manufacturers. In all
such cases, the benefit of these undertakings will be passed on to the user.
CASELLA CEL’s liability is limited to items of their own manufacture, and they do not
accept liability for any loss resulting from the operation or interpretation of the results
from this equipment. To obtain repair under warranty, the instrument should be
packed and returned in it’s original packing or an equivalent either to CASELLA
CEL’s local agent, or in the case of U.K. domestic sales, to the CASELLA CEL
Service Department at Bedford. Please include the following information:
Instrument Type(s), Serial Number(s) and Firmware Version Number(s), Customer
name and address, Contact name and phone number, details of any PC and
Software involved, including Version Number(s), reason for returning the equipment
with a detailed description of the fault and a list of any error messages that may have
been displayed.
The necessary adjustments or repairs will be carried out, and the instrument returned
as soon as possible. After the warranty has expired (except on approved accounts)
service work is undertaken against quotations and all packing and transit costs are
charged extra.
Back to Index
28
Casella CEL Limited
8. APPENDIX A
GLOSSARY OF TERMS
This Appendix gives a glossary of the acoustic terminology used in this manual. For
further information, please contact Casella CEL or your local representative.
A, C and Z WEIGHTING (WEIGHTED)
A standard weighting of the audible frequencies designed to approximate the
response of the human ear to noise.
ACOUSTIC CALIBRATOR
An instrument that provides a reference noise source with a standard level and
frequency used to calibrate and check the performance of sound level meters and
noise dosimeters.
Decibel (dB)
The standard physical unit for measuring sound level and noise exposure.
dB(A)
A-weighted sound level in decibels.
dB(C)
C-weighted sound level in decibels.
dB(Z)
Z-weighted sound level in decibels.
FAST TIME WEIGHTING
A standard time weighting applied by the sound level measurement instrument.
LAE
The A-weighted exposure level is the level that would contain the same amount of
energy in one second as the actual noise has during the whole measurement period.
LAeq
The A-weighted equivalent level is the level that would contain the same amount of
noise energy as in the actual noise, effectively giving an average level over the
measurement period. Following the ISO procedures, doubling the energy results in a
3dB change in the Leq. This is denoted by exchange rate Q=3. For example, if the
noise level in a factory was a constant 85dB and the measurement period was 4
hours, the LAeq would be 85dB(A). The calculation of LAeq does not use a threshold
as in the calculation of LAVG, except for the LAEQ (T80) parameter defined for the
ACGIH standard.
LAF
The A-weighted sound level measured with Fast time weighting.
LAS
The A-weighted sound level measured with Slow time weighting.
LASmax
The maximum A-weighted sound level measured with Slow time weighting.
LAVG
This is a parameter used in OSHA measurements. It is the average sound level over
the measurement period (equivalent to Leq). Normally the term is used when the
exchange rate Q is some value other than 3, such as for measurements used for the
OSHA Hearing Conservation Amendment with Q=5. A Threshold value is used
during the calculation of LAVG, where any levels below the threshold are not
Casella CEL Limited
29
included. For example, assume the threshold level is set to 80dB and the exchange
rate is 5dB (Q = 5). If a one hour measurement was taken in an environment where
the noise levels vary between 50 and 70dB, the sound level would never exceed the
Threshold so the instrument would record no value for the LAVG. However, if the
sound level exceeds the 80dB Threshold for only a few seconds, only these seconds
will contribute to the LAVG, giving a level of around 40dB, which is much lower than
the actual ambient sound levels in the measured environment.
LCpeak
The peak C-weighted sound level.
LEP,d (LEX,8h)
This is the daily personal noise exposure defined by ISO 1999. It is the LAeq
normalised to an 8 hour Criterion Time, i.e. a standard day. Assuming the noise level
for the rest of the 8 hour reference period is “quiet”, the LEP,d will be: lower than the
Leq when the measurement duration is less than 8 hours, equal to the Leq for a
measurement of 8 hours, higher than the Leq for measurements longer than 8 hours.
For example, if a noise measurement was made for 4 hours and the LAeq value was
90dB(A), the LEP,d value would be calculated to be 87dB(A) as the measurement
duration is half the 8 hour Criterion Time and the exchange rate is 3 dB.
LCeq
The C-weighted equivalent level is the level that would contain the same amount of
noise energy as in the actual noise, effectively giving an average level over the
measurement period. Following the ISO procedures, doubling the energy results in a
3dB change in the Leq. This is denoted by exchange rate Q=3.
PEAK
The maximum level in dB reached by the sound pressure at any instant during a
measurement period. With the CEL-62X, peak is measured with either C, Z or A
weighting. It is the true peak level of the pressure wave, which should not be
confused with the highest sound pressure level, termed Lmax.
SLOW TIME WEIGHTING
A standard time weighting applied by the noise measurement instrument.
SPL
The sound pressure level. This is the basic physical measure of noise, and is
normally expressed in dB.
THRESHOLD
A threshold level below which sound is excluded from calculation. OSHA
measurements use an 80 dB threshold.
Back to Index
30
Casella CEL Limited
9. APPENDIX B
ADDITIONAL INFORMATION
IEC61672-1:2002 section 9.3 (Information for testing)
a) Reference Sound Pressure Level
The reference sound pressure level is selectable to be 94 dB or 114 dB.
b) Reference Level Range
The CEL-62X is a single level range instrument of 0 to 140 dB.
c) Microphone Reference Point
The microphone reference point is the centre of the diaphragm of the
microphone. The 0o reference direction is perpendicular to the microphone
diaphragm.
d) Acoustical Frequency Response Testing
The pressure to free field correction data for the CEL-251 microphone used for
periodic testing.
Frequency
0o Free
Field
Corrections
using a
Bruel &
Kjear 4226
Calibrator
Hz
31.5
63
125
250
500
1000
2000
4000
8000
12500
16000
dB
-0.1
-0.2
-0.2
-0.2
-0.2
0
0.3
0.7
2.8
5.3
6.4
Casella CEL Limited
0o Free
Field
Corrections
with Wind
Screen
using a
Bruel &
Kjear 4226
Calibrator
dB
-0.1
-0.2
-0.2
-0.2
-0.2
0.1
0.7
1.4
2.5
4.1
4.5
0o Free Field
Corrections
using a
Bruel &
Kjear
UA0033
Electrostatic
Actuator
dB
-0.1
-0.2
-0.2
-0.2
-0.2
0
0.3
0.8
3.1
6.2
7.8
0o Free Field
Corrections
with Wind
Screen using
a Bruel &
Kjear
UA0033
Electrostatic
Actuator
dB
-0.1
-0.2
-0.2
-0.2
-0.2
0.1
0.7
1.5
2.8
5.0
5.9
Expanded
Uncertainty
of
Corrections
at 95%
probability
(k=2)
dB
0.2
0.2
0.2
0.2
0.2
0.2
0.3
0.3
0.4
0.6
0.6
31
e) Linear Operating Range
The lower and upper limits of the linear operating ranges for electrical input, or
using a CEL-251 microphone; (add 10dB to the lower limit when using a CEL-252
microphone)
Weighting
A
C
Z
C Peak
31.5 Hz
30 to 100
32 to 137
38 to 140
65 to 140
1 kHz
30 to 140
32 to 140
38 to 140
65 to 143
4 kHz
30 to 141
32 to139
38 to 140
65 to 142
8 kHz
30 to 138
32 to 136
38 to 140
65 to 139
12.5 kHz
30 to 134
32 to 132
38 to 140
65 to 135
f) Linearity Measurements Starting Point
The starting point for measuring level linearity errors is 114dB.
g) Electrical Input
The input device to apply electrical signals to the pre-amplifier is a series 18pF
+/- 5% capacitor. The CEL-516-02 can be used for this purpose. The electrical
self generated noise can be measured with the supplied shorting plug attached to
the CEL-516-02.
h) Self Generated Noise
Combination of CEL-251 microphone thermal noise and meter electrical noise.
Weighting
Electrical
Electrical
Microphone
Combined
Combined
Typical dB
Max dB
Thermal dB
Typical dB
Max dB
A
18.0
20.0
16.0
20.0
22.0
C
21.0
23.0
16.8
22.0
24.0
Z
28.0
30.0
16.8
28.0
30.5
Note: The CEL-252 microphone has a thermal noise of typically 20dBA – the
combined typical and max noise levels will be 1.5dB higher than above.
i) Highest Level
The highest sound pressure level designed to be measured by the CEL-62X
sound level meter when fitted with a 50mV/Pa microphone is 140dB. The highest
peak to peak voltage that can be applied to the pre-amplifier input via the CEL516-02 is 28.5V.
j) Power Supply Voltage Range
The CEL-62X can be powered from three internally fitted AA batteries, or an
external 12VDC supply (2.1mm connector, tip +ve), or 5VDC USB supply from a
PC.
Internal batteries – range 3 to 5 volts. The battery condition symbol will start to
flash as a warning when the batteries have discharged to 3.3 volts, and the meter
will stop a run and turn off when the batteries have discharged to less that 3 volts
to ensure no data is measured that does not meet the requirements of IEC
61672.
32
Casella CEL Limited
12VDC supply range is 9 to 14 volts.
USB supply range is 4.5 to 5.5 volts.
k) Display Device
The display device will display the complete linear operating range.
l) Environmental Stabilisation Time
The typical time to stabilise after sudden changes in environment conditions.
5 minutes after a 10 oC change in temperature.
5 minutes after a 30% change in humidity (non-condensing).
15 seconds after a 5kPa change in ambient pressure.
m) Electric Field Strength Greater Than 10 V/m
The CEL-62X was not tested for field strengths greater than 10 V/m.
n) EMC Emissions
Emissions were no greater in any one plane or any mode of operation.
o) EMC Susceptibility
The CEL-62X has slightly higher susceptibility with the Y plane facing the
radiating antenna.
X is in the direction of the microphone, Z is in the direction of the display, and Y is
in the direction side-on to the case.
Casella CEL Limited
33
Casella CEL-62X with CEL-251 Microphone Free Field response with and
without Wind Screen.
Nominal
Frequency
Hz
250
315
400
500
630
800
1000
1250
1600
2000
2240
2500
2800
3150
3550
4000
4500
5000
5600
6300
7100
8000
8500
9000
9500
10000
10600
11200
11800
12500
13200
14000
15000
16000
17000
18000
19000
20000
Actual
Frequency
0 Degree
Free Field
Response
0 Degree
Free Field
Corrections
Effect of
Wind
Screen
0 Degree
Free Field
Response
with wind
Screen
0 Degree
Free Field
Corrections
with Wind
Screen
Expanded
uncertainty
of
Corrections
(k=2)
Hz
dB
dB
dB
dB
dB
dB
251.19
316.23
398.11
501.19
630.96
794.33
1000.00
1258.92
1584.89
1995.26
2238.72
2511.88
2818.38
3162.27
3548.13
3981.07
4466.83
5011.86
5623.40
6309.56
7079.45
7943.27
8413.94
8912.49
9440.59
9999.98
10592.52
11220.16
11885.00
12589.23
13335.19
14125.35
14962.33
15848.90
16788.00
17782.76
18836.45
19952.58
0.0
-0.1
0.1
0.1
0.0
0.1
-0.1
0.0
-0.4
-0.2
0.1
0.4
0.2
-0.3
-0.9
0.0
0.0
-0.1
-0.4
-0.7
-0.1
-0.3
-0.4
-0.6
-0.8
-0.9
-0.8
-0.6
-1.0
-0.7
-1.0
-0.9
-1.0
-0.9
-1.0
-1.0
-1.0
-1.3
0.0
0.1
-0.1
-0.1
0.0
-0.1
0.1
0.0
0.4
0.2
-0.1
-0.4
-0.2
0.3
0.9
0.0
0.0
0.1
0.4
0.7
0.1
0.3
0.4
0.6
0.8
0.9
0.8
0.6
1.0
0.7
1.0
0.9
1.0
0.9
1.0
1.0
1.0
1.3
0.0
0.0
0.0
0.0
0.1
0.1
0.1
0.2
0.3
0.4
0.4
0.5
0.5
0.6
0.7
0.7
0.7
0.6
0.5
0.2
-0.1
-0.3
-0.4
-0.5
-0.5
-0.7
-0.7
-0.9
-1.0
-1.2
-1.3
-1.4
-1.5
-1.9
-2.1
-2.4
-2.7
-2.6
0.0
-0.1
0.1
0.1
0.1
0.2
0.0
0.2
-0.1
0.2
0.5
0.9
0.7
0.3
-0.2
0.7
0.7
0.5
0.1
-0.5
-0.2
-0.6
-0.8
-1.1
-1.3
-1.6
-1.5
-1.5
-2.0
-1.9
-2.3
-2.3
-2.5
-2.8
-3.1
-3.4
-3.7
-3.9
0.0
0.1
-0.1
-0.1
-0.1
-0.2
0.0
-0.2
0.1
-0.2
-0.5
-0.9
-0.7
-0.3
0.2
-0.7
-0.7
-0.5
-0.1
0.5
0.2
0.6
0.8
1.1
1.3
1.6
1.5
1.5
2.0
1.9
2.3
2.3
2.5
2.8
3.1
3.4
3.7
3.9
Corrections below 250Hz are 0.0dB
34
Casella CEL Limited
0.16
0.16
0.16
0.16
0.17
0.18
0.19
0.19
0.20
0.21
0.21
0.21
0.22
0.22
0.23
0.23
0.25
0.26
0.28
0.29
0.32
0.35
0.38
0.41
0.44
0.46
0.48
0.50
0.52
0.53
0.55
0.57
0.59
0.60
0.60
0.60
0.60
0.60
CEL-62X with CEL-251 Microphone directional response (dB) relative to zero
degrees.
Orientation of CEL-62X - Display at 0 degrees relative to ground.
Nominal
Frequency
(Hz)
Actual
Frequency
(Hz)
0
Deg
10
Deg
20
Deg
30
Deg
40
Deg
50
Deg
60
Deg
70
Deg
80
Deg
90
Deg
100
Deg
110
Deg
120
Deg
130
Deg
140
Deg
150
Deg
500
501.19
0.00
0.01
0.01
0.00
-0.02
-0.05
-0.09
-0.20
-0.20
-0.26
-0.32
-0.35
-0.37
-0.36
-0.36
-0.34
630
630.96
0.00
0.02
0.04
0.05
0.06
0.06
0.05
-0.06
-0.06
-0.15
-0.25
-0.33
-0.38
-0.40
-0.41
-0.41
800
794.33
0.00
0.01
0.02
0.02
0.01
0.01
0.01
0.01
0.01
-0.04
-0.14
-0.29
-0.41
-0.45
-0.46
-0.42
1000
1000.00
0.00
0.01
0.03
0.03
0.04
0.05
0.06
0.02
0.02
0.01
-0.02
-0.14
-0.31
-0.38
-0.34
-0.29
1250
1258.92
0.00
0.02
0.03
0.01
-0.08
-0.21
-0.33
-0.15
-0.15
-0.05
-0.07
-0.15
-0.32
-0.59
-0.63
-0.51
1600
1584.89
0.00
0.00
0.00
-0.04
-0.09
-0.12
0.01
0.00
0.00
-0.07
0.20
0.18
0.03
-0.29
-0.61
-0.45
2000
1995.26
0.00
0.03
0.06
0.02
-0.20
-0.49
-0.36
-0.30
-0.30
-0.13
-0.25
-0.12
0.02
-0.19
-0.69
-0.98
2240
2238.72
0.00
-0.01
-0.12
-0.35
-0.50
-0.40
-0.56
-0.46
-0.46
-0.63
-0.41
-0.64
-0.24
-0.45
-0.94
-1.28
2500
2511.88
0.00
-0.08
-0.35
-0.60
-0.55
-0.70
-1.09
-1.37
-1.37
-0.98
-1.05
-0.85
-0.86
-0.75
-1.08
-1.60
2800
2818.38
0.00
-0.03
-0.06
0.06
-0.01
-0.76
-0.93
-1.59
-1.59
-1.60
-0.92
-1.19
-1.29
-0.64
-0.91
-1.84
3150
3162.27
0.00
-0.07
-0.04
0.29
0.41
0.11
-0.07
-0.72
-0.72
-0.97
-1.26
-0.70
-0.73
-0.69
-0.46
-1.24
3550
3548.13
0.00
-0.02
0.06
0.58
0.95
0.50
0.87
-0.54
-0.54
-0.40
-0.38
-0.20
-0.48
-0.55
-0.22
-0.66
4000
3981.07
0.00
-0.10
-0.58
-1.00
-0.75
-0.96
-0.29
-1.17
-1.17
-1.84
-1.75
-1.67
-1.22
-1.86
-1.32
-1.90
4500
4466.83
0.00
0.12
0.26
-0.18
-0.57
-1.11
-0.76
-1.06
-1.06
-1.70
-2.28
-2.28
-1.23
-1.70
-1.44
-1.52
5000
5011.86
0.00
-0.12
-0.57
-0.28
-0.41
-0.83
-1.52
-1.00
-1.00
-1.77
-2.63
-2.54
-2.24
-1.69
-2.71
-2.05
5600
5623.40
0.00
-0.13
-0.10
-0.07
-0.39
-0.88
-1.05
-1.10
-1.10
-1.21
-2.21
-2.66
-2.52
-1.59
-2.57
-1.97
6300
6309.56
0.00
0.03
0.50
0.47
0.22
-0.09
-0.88
-1.62
-1.62
-1.27
-1.82
-2.42
-2.64
-2.36
-2.36
-2.59
7100
7079.45
0.00
0.04
0.07
-0.45
-1.21
-1.38
-1.33
-3.14
-3.14
-2.42
-3.01
-4.30
-4.12
-3.39
-2.70
-4.15
8000
7943.27
0.00
-0.10
-0.41
-0.55
-0.61
-1.36
-1.79
-2.97
-2.97
-3.78
-2.67
-4.08
-4.64
-3.96
-3.80
-4.48
8500
8413.94
0.00
0.19
-0.15
-0.40
-1.00
-1.13
-2.07
-2.69
-2.69
-4.11
-3.20
-3.82
-5.66
-4.53
-4.05
-4.45
9000
8912.49
0.00
-0.21
-0.18
-0.75
-1.03
-1.72
-1.96
-2.25
-2.25
-4.89
-3.90
-3.40
-6.09
-4.88
-4.44
-4.72
9500
9440.59
0.00
0.33
-0.21
-0.23
-0.58
-1.18
-2.38
-2.72
-2.72
-4.04
-4.07
-3.56
-6.49
-4.93
-4.45
-5.00
10000
9999.98
0.00
-0.32
-0.55
-0.90
-1.43
-2.00
-2.30
-3.20
-3.20
-3.74
-5.31
-4.73
-6.06
-6.30
-4.77
-4.87
10600
10592.52
0.00
-0.21
-0.05
-0.51
-0.86
-1.67
-2.42
-4.85
-4.85
-4.05
-5.98
-5.57
-5.96
-6.64
-5.33
-5.81
11200
11220.16
0.00
0.17
-0.38
-0.62
-1.24
-1.87
-2.57
-4.84
-4.84
-4.29
-6.15
-5.55
-6.62
-7.64
-5.84
-6.57
11800
11885.00
0.00
0.10
-0.45
-0.71
-1.39
-1.95
-2.83
-4.67
-4.67
-5.10
-5.99
-6.49
-6.43
-8.77
-6.67
-7.11
12500
12589.23
0.00
-0.01
-0.59
-1.03
-1.44
-2.32
-3.12
-4.75
-4.75
-6.33
-6.14
-7.87
-6.60
-9.13
-7.33
-7.62
Maximum expanded uncertainty of above data with 95% probability (k=2)
500Hz to 1kHz
0.3dB
>1kHz to 4kHz
0.5dB
>4kHz to 8kHz
1.0dB
>8kHz to 12.5kHz
1.5dB
Casella CEL Limited
35
CEL-62X with CEL-251 Microphone directional response (dB) relative to zero
degrees.
Orientation of CEL-62X - Display at 90 degrees relative to ground.
Nominal
Frequency
(Hz)
Actual
Frequency
(Hz)
0
Deg
10
Deg
20
Deg
30
Deg
40
Deg
50
Deg
60
Deg
70
Deg
80
Deg
90
Deg
100
Deg
110
Deg
120
Deg
130
Deg
140
Deg
150
Deg
500
501.19
0.00
0.00
0.00
0.00
-0.01
-0.03
-0.06
-0.11
-0.16
-0.21
-0.25
-0.27
-0.28
-0.28
-0.28
-0.27
630
630.96
0.00
0.00
0.02
0.04
0.06
0.07
0.06
0.02
-0.04
-0.12
-0.21
-0.28
-0.33
-0.34
-0.34
-0.34
800
794.33
0.00
0.00
0.00
0.00
0.00
0.01
0.02
0.04
0.05
0.02
-0.07
-0.20
-0.31
-0.35
-0.36
-0.33
1000
1000.00
0.00
0.01
0.01
0.02
0.03
0.04
0.05
0.04
0.03
0.04
0.04
-0.08
-0.26
-0.34
-0.30
-0.23
1250
1258.92
0.00
0.01
0.03
0.02
-0.07
-0.22
-0.34
-0.31
-0.15
-0.05
-0.03
-0.05
-0.24
-0.59
-0.65
-0.51
1600
1584.89
0.00
-0.01
-0.03
-0.09
-0.15
-0.15
0.02
0.16
0.01
-0.05
0.24
0.24
0.11
-0.25
-0.64
-0.47
2000
1995.26
0.00
-0.01
0.01
-0.05
-0.28
-0.50
-0.36
-0.20
-0.31
-0.07
-0.26
-0.09
0.15
-0.11
-0.73
-1.05
2240
2238.72
0.00
-0.07
-0.24
-0.49
-0.56
-0.36
-0.54
-0.87
-0.59
-0.54
-0.28
-0.54
-0.10
-0.27
-0.92
-1.35
2500
2511.88
0.00
-0.10
-0.30
-0.44
-0.42
-0.80
-1.12
-0.82
-1.25
-0.95
-0.79
-0.72
-0.75
-0.45
-1.02
-1.58
2800
2818.38
0.00
-0.02
0.01
0.14
-0.02
-0.76
-0.84
-1.22
-1.37
-1.78
-1.18
-0.94
-1.12
-0.34
-0.69
-1.88
3150
3162.27
0.00
0.07
0.26
0.57
0.41
0.02
-0.06
-1.16
-0.83
-0.68
-1.38
-0.80
-0.52
-0.26
-0.21
-1.36
3550
3548.13
0.00
-0.12
0.07
0.77
1.23
1.10
1.03
0.44
-0.53
-0.38
-0.31
-0.26
-0.45
-0.49
0.62
-0.59
4000
3981.07
0.00
-0.27
-0.82
-1.02
-0.98
-0.98
0.18
-0.16
-1.03
-1.78
-1.55
-1.66
-1.13
-1.64
-0.51
-1.49
4500
4466.83
0.00
0.14
0.10
-0.57
-0.96
-2.12
-1.25
-0.69
-1.10
-2.06
-2.95
-2.20
-2.33
-1.84
-1.34
-1.50
5000
5011.86
0.00
-0.22
-0.42
0.14
-0.03
-0.18
-2.12
-1.99
-0.54
-1.24
-2.52
-2.73
-2.35
-1.45
-2.52
-1.18
5600
5623.40
0.00
-0.14
-0.12
-0.60
-0.45
-0.69
-0.37
-2.01
-1.84
-0.68
-2.16
-2.45
-2.31
-2.50
-2.53
-0.85
6300
6309.56
0.00
0.30
0.96
0.94
0.22
-1.14
-1.36
-0.25
-1.95
-2.02
-1.50
-2.13
-3.21
-3.48
-2.99
-1.10
7100
7079.45
0.00
0.16
0.06
-0.99
-1.64
-1.27
-0.83
-2.04
-3.21
-2.66
-2.37
-4.39
-3.44
-2.61
-3.21
-4.29
8000
7943.27
0.00
-0.28
-0.34
-0.55
-0.47
-1.52
-1.83
-1.99
-2.41
-4.06
-3.14
-3.68
-5.20
-3.60
-4.02
-4.53
8500
8413.94
0.00
-0.08
-0.66
-0.73
-1.06
-1.11
-2.71
-2.49
-2.77
-4.26
-4.25
-3.27
-6.01
-4.69
-4.62
-5.45
9000
8912.49
0.00
0.01
0.15
-0.40
-0.93
-1.50
-1.36
-3.30
-2.57
-3.43
-4.29
-2.58
-5.63
-4.75
-4.34
-5.53
-5.91
9500
9440.59
0.00
-0.12
-0.61
-0.98
-1.07
-1.95
-2.23
-3.69
-3.05
-3.79
-6.18
-3.46
-7.41
-4.96
-5.05
10000
9999.98
0.00
-0.12
-0.03
-0.36
-1.42
-1.54
-2.70
-2.36
-3.47
-3.48
-4.85
-4.69
-6.53
-6.43
-5.02
-5.12
10600
10592.52
0.00
0.09
-0.66
-0.64
-0.95
-2.05
-2.18
-3.76
-5.49
-4.18
-5.30
-7.67
-4.94
-7.23
-5.49
-5.74
11200
11220.16
0.00
-0.16
-0.36
-1.00
-1.78
-2.14
-3.28
-3.76
-4.71
-4.82
-5.82
-7.95
-5.48
-8.29
-6.30
-6.97
11800
11885.00
0.00
-0.17
-0.40
-1.05
-1.36
-2.36
-3.06
-3.89
-4.67
-6.56
-6.05
-8.09
-5.45
-9.54
-6.80
-7.32
12500
12589.23
0.00
-0.34
-0.59
-1.05
-2.02
-2.69
-3.45
-4.72
-5.59
-7.47
-6.61
-8.44
-6.05
-10.78
-7.16
-8.12
Maximum expanded uncertainty of above data with 95% probability (k=2)
500Hz to 1kHz
0.3dB
>1kHz to 4kHz
0.5dB
>4kHz to 8kHz
1.0dB
>8kHz to 12.5kHz
1.5dB
36
Casella CEL Limited
Sound Calibrators – Level Corrections
Sound level calibrators apply sound pressure to a microphone in a closed cavity.
The response of a microphone in a free field at 1kHz will be slightly different to that of
a pressure field. Also some calibrators are affected by the volume of the microphone
changing the volume of the calibrator cavity.
The wind screen has an affect on the free field response at 1kHz and this can be
compensated for during calibration.
Calibration corrections for the CEL-251 and CEL-252 Microphones.
Calibrator
Casella CEL-110/1
Casella CEL-110/2
Bruel & Kjear 4231
Cirrus CR:515
Calibration Level
Correction no Wind
Screen
-0.1dB
-0.1dB
-0.1dB
-0.1dB
Calibration Level
Correction with
Wind Screen
0.0dB
0.0dB
0.0dB
0.0dB
IEC 60942
Type 1
Type 2
Type 1 approved
Type 1 approved
Examples
The CEL-62X can be calibrated at a nominal level of 94dB or 114dB dependent on
the type of calibrator used.
If a CEL-110/1 is used and the certified output of the calibrator is 113.98dB, and it is
intended to use the sound level meter without the wind screen, then the calibration
level will need to be set to 113.88, rounded to 113.9dB.
Calibrator level
113.98
Correction
-0.1
Calibration level =
113.88 rounded to 113.9dB
If a Cirrus CR:515 is used and the certified output of the calibrator is 94.04dB, and it
is intended to use the sound level meter with the wind screen fitted, then the
calibration level will need to be set to 94.04, rounded to 94.0dB
Calibrator level
94.04
Correction
0.0
Calibration level =
94.04 rounded to 94.0dB
See Section G. in the manual to set the calibration level.
See Section K. in the manual to calibrate the sound level meter.
Casella CEL Limited
37
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