Rion NA-28 User manual

3-20-41 Higashimotomachi, Kokubunji, Tokyo 185-8533, Japan
http://www.rion.co.jp/english/
INSTRUCTION MANUAL
SOUND LEVEL METER
NA-28

i
Organization of the NA-28 Documentation
Documentation for the Sound Level Meter NA-28 comes in three parts, as
listed below.
Instruction Manual (this document)
Describes operating procedures for the Sound Level Meter NA-28, connec-
tion and use of peripheral equipment such as a level recorder and printer,
and use of the memory card.
Serial Interface Manual
Describes communication with a computer, using the serial interface built
into the Sound Level Meter NA-28. The manual covers the communication
protocol, use of control commands for the sound level meter, format of data
output by the sound level meter, and other topics.
Technical Notes
This document provides in-depth information about sound level meter
performance, microphone construction and characteristics, inuence of
extension cables and windscreen on the measurement, and other topics.
* Company names and product names mentioned in this manual are usually
trademarks or registered trademarks of their respective owners.

ii

iii
Organization of This Manual
This manual describes the features, operation and other aspects of the Sound Level
Meter NA-28 (with 1/3 octave analysis function). If the unit is used together with
other equipment to congure a measurement system, consult the documentation of
all other components as well. The following pages contain important information
about safety. Be sure to read and observe these in full.
This manual contains the following sections.
Outline
Gives basic information about the unit.
Controls and Functions
Briey identies and explains the operation keys and connectors and all
other parts of the unit.
Preparations
Explains how to check the unit before use and how to install and set up the
unit for measurement.
Calibration
Explains how to calibrate the unit for measurement.
Power On/Off
Explains how to operate the POWER key of the unit.
Reading the Display
Explains symbols and other information shown on the display of the unit.
Measurement
Explains the basic procedures for measurement.
Store Operation
Explains how to store measurement data.

iv
Memory Card
Explains how to use a memory card with the unit.
Input/Output Connectors
Explains the input and output connectors of the unit.
Default Settings
Lists the factory default settings of the unit.
Setup File
Explains how to start up the unit using settings saved in a setup le.
Optional Accessories
Explains how to use the optional microphone extension cable, printer, and
level recorder with the unit.
Specications
Lists the technical specications of the unit.

v
FOR SAFETY
In this manual, important safety instructions are specially marked as shown
below. To prevent the risk of death or injury to persons and severe damage
to the unit or peripheral equipment, make sure that all instructions are fully
understood and observed.
Caution
Important
Disregarding instructions
printed here incurs the risk of
injury to persons and/or dam-
age to peripheral equipment.
Disregarding instructions
printed here incurs the risk of
damage to the product.
Mentioned about the tips to
use this unit properly. (This
messages do not have to do
with safety.)
Note

vi

vii
Quantier notation
(Sound level and sound pressure level are expressed uniformly as sound pres-
sure level, distinguished by the use of frequency weighting.)
Measurement value
The time weighting characteristics
F, S, 10 ms I
Lp
Sound pressure
level
A-weighted sound pressure level LAF, LAS, LA10ms LAI
C-weighted sound pressure level LCF, LCS, LC10ms (LCI)
Z-weighted sound pressure level LZF, LZS, LZ10ms (LZI)
Leq
Equivalent
continuous
sound level
Equivalent continuous A-weighted
sound level LAeq LAIeq
Equivalent continuous C-weighted
sound level LCeq (LCIeq)
Equivalent continuous Z-weighted
sound level LZeq (LZIeq)
LE
Sound exposure
level
A-weighted sound exposure level LAE (LAIE)
C-weighted sound exposure level LCE (LCIE)
Z-weighted sound exposure level LZE (LZIE)
Lmax,Lmin
Maximum sound
level
Maximum A-weighted sound level LAFmax, LASmax, LA10msmax LAImax
Maximum C-weighted sound level LCFmax, LCSmax, LC10msmax (LCImax)
Maximum Z-weighted sound level LZFmax, LZSmax, LZ10msmax (LZImax)
LN
Percentile sound
level
Percentile A-weighted sound level LAFNn, LASNn, LA10msNn (LAINn)
Percentile C-weighted sound level LCFNn, LCSNn, LC10msNn (LCINn)
Percentile Z-weighted sound level LZFNn, LZSNn, LZ10msNn (LZINn)
Lpeak
Peak sound level
A-weighted peak sound level (LApeak) ---
C-weighted peak sound level LCpeak ---
Z-weighted peak sound level LZpeak ---
Ltm5
Takt-max sound
level
Takt-max A-weighted sound level LAtm5 ---
Takt-max C-weighted sound level (LCtm5) ---
Takt-max Z-weighted sound level (LZtm5) ---
• Z-weighted level is the same as a existing at-weighted level.
• The combination of peak sound pressure level and takt-max with I
characteristics does not exist.
• Measurement value shown in brackets ( ) indicates items that can be
displayed as operation steps but are not used or not suitable.

viii

ix
Quantier Notation of Sound Level Meter NA-28 According to International
Standards and JIS
(Excerpts from ISO 1996, 3891, IEC 61672-1, JIS Z 8202, 8731)
NA-28
notation Description Frequency weighting
ISO
notation
IEC
notation
JIS
notation
LZSound level ZLp—Lp
LAA-weighted sound level ALpA—LpA
LCC-weighted sound level C———
LZeq
Equivalent continuous
sound level Z———
LAeq
Equivalent continuous
A-weighted sound level ALAeq,TLAeq,TLAeq,T
LCeq
Equivalent continuous
C-weighted sound level C—LCeq,T—
LZE Sound exposure level Z———
LAE
A-weighted sound
exposure level ALAE LAE,TLAE
LCE
C-weighted sound
exposure level C———
LAN
LA05
Percentile A-weighted
sound level ALAN,T
LA5,T—
LAN,T
LA5,T
LA10 LA10,T—LA10,T
LA50 LA50,T—LA50,T
LA90 LA90,T—LA90,T
LA95 LA95,T—LA95,T
LAmax
Maximum A-weighted
sound level A———
LAmin
Minimum A-weighted
sound level A———
LCpk
C-weighted peak sound
level C—LCpeak —
• Z-weighted level is the same as a existing at-weighted level.

x

xi
Precautions
Operate the unit only as described in this manual.
The NA-28 is a precision instrument. Protect it from shocks and vibrations.
Take special care not to touch the microphone diaphragm. The diaphragm
is a very thin metal lm which can easily be damaged.
Use only the microphone/preamplier assembly with the number as shown
on the name plate of the unit.
Ambient conditions for operation of the unit are as follows: temperature
range -10 to +50°C, relative humidity 10 to 90%RH.
Protect the unit from water, dust, extreme temperatures, humidity, and
direct sunlight during storage. Also keep the unit away from air with
high salt or sulphur content, gases, and stored chemicals during storage
and use.
Always turn the unit off after use. Remove the batteries from the unit if
it is not to be used for a long time (a week or more).
When disconnecting cables, always grasp the plug and do not pull the
cable.
Before using the unit and before putting it away, always check that the
microphone grid has not become loose. If this has happened, refasten the
microphone grid rmly and then use or store the unit.
Clean the unit only by wiping it with a soft, dry cloth or, when neces-
sary, with a cloth lightly moistened with water. Do not use any solvents,
cleaning alcohol or chemical cleaning agents.
Do not try to disassemble or alter the unit. In case of an apparent malfunc-
tion, do not attempt any repairs. Note the condition of the unit clearly and
contact the supplier.
Do not tap the LCD panel or other surfaces of the unit with a pointed
object such as a pencil, screwdriver, etc.
Take care that no conductive objects such as wire, metal scraps, conduc-
tive plastics etc. can get into the unit.

xii
To ensure continued accuracy, have the unit checked and serviced at
regular intervals. Contact the supplier.
Dispose of the unit and of batteries only according to national and local
regulations at the place of use.
This product can be used in any areas including residential areas.
To conform to the EU requirement of the Directive on
Waste Electrical and Electronic Equipment, the symbol
mark on the right is shown on the instrument.

xiii
Contents
Organization of the NA-28 Documentation ..................................... i
Organization of This Manual ........................................................ iii
Outline ............................................................................................1
Controls and Functions ...................................................................3
Front View.................................................................................3
Operation key panel .............................................................4
Bottom View..............................................................................7
Rear View..................................................................................8
Preparations ....................................................................................9
Power.........................................................................................9
AC adapter ......................................................................... 11
Backup Battery ..................................................................11
Windscreen (WS-10)................................................................12
Diffuse Field Correction ..........................................................13
Tripod Mounting......................................................................13
Memory Cards (CF Card) and Program Cards......................... 14
Microphone Extension Cables (EC-04 series) ..........................15
Connection to a Printer............................................................ 17
Connection to a Level Recorder (LR-07, LR-20A) ...................17
Connection to a Computer .......................................................18
Setting the Date and Time .......................................................19
Measurement in a dark location ...............................................21
Sub Channel Settings...............................................................22
Trigger Mode Settings .............................................................23
Sleep Mode ........................................................................26
Comparator Output ..................................................................30
Language Selection..................................................................33
Calibration ....................................................................................34
Electrical calibration................................................................34
Acoustic calibration with Sound Calibrator NC-74...................36

xiv
Power On/Off................................................................................38
To turn the unit on ...................................................................38
To turn the unit off ..................................................................39
Power-on mode ........................................................................39
Reading the Display ......................................................................40
Sound level meter display ........................................................40
Analysis screen........................................................................45
T-L (Time/Level) display screen..............................................45
Numeric display screen............................................................46
Indicator messages...................................................................47
Menu List Screen.....................................................................48
System................................................................................48
Display ............................................................................... 51
I/O (Input/Output)..............................................................52
Store...................................................................................54
Measurement......................................................................55
Print ...................................................................................58
Recall.................................................................................59
Measurement................................................................................. 61
Sound Level Measurement....................................................... 61
Equivalent Continuous Sound Level (LAeq) Measurement ........64
Sound Exposure Level (LAE) Measurement..............................69
Maximum Sound Level (Lmax)
and Minimum Sound Level (Lmin) Measurement .....................71
Selecting the Lmax/Lmin type...............................................74
Percentile Sound Level (LN) Measurement...............................75
Additional Processing Value (Lpeak, LAtm5) Measurement ........78
Back-Erase Function ................................................................80
Marker .....................................................................................82
Max Hold.................................................................................83
Delayed Measurement..............................................................84

xv
Store Operation .............................................................................86
Inserting and Removing the CF Card ......................................88
Manual ....................................................................................89
Auto1 .......................................................................................95
Auto2..................................................................................... 101
Screen Hard Copy .................................................................104
Memory Card.............................................................................. 105
Using a memory card............................................................. 105
Data Size Information ...........................................................106
About memory cards..............................................................108
About the store data format ...................................................109
Formatting (Initializing) a CF Card....................................... 110
Input/Output Connectors............................................................. 111
AC OUTPUT......................................................................... 111
DC OUTPUT......................................................................... 113
TRIG IN/COMP OUT jack.................................................... 114
Default Settings........................................................................... 116
Setup File.................................................................................... 118
Preparing a setup le for automatic loading........................... 119
Automatic loading of settings at startup.................................120
Saving a setup le.................................................................. 121
Copying a setup le to CF card..............................................122
Optional Accessories...................................................................123
Microphone Extension Cables (EC-04 series) ........................123
Printer....................................................................................124
Level Recorder LR-07/LR-20A..............................................127
Program Cards....................................................................... 129
Remote control ......................................................................130
Specications .............................................................................. 132

xvi

1
Outline
The Sound Level Meter NA-28 allows octave and 1/3 octave band analysis in
real time. It conforms to legal requirements for quantity measurements and to
JIS and IEC standards. It supports diffuse sound eld measurements and also
meets standard requirements when the supplied windscreen is mounted.
The NA-28 consists of the 1/2-inch electret condenser microphone UC-59,
preamplier NH-23, and the main unit. The main unit is equipped with an
LCD panel, operation keys, AC and DC output connector, USB port, com-
parator output, external trigger input, and infrared remote control sensor.
The unit supports real-time octave band analysis in the range from 16 Hz to
16 kHz, and real-time 1/3 octave band analysis in the range from 12.5 Hz to
20 kHz. It is also possible to perform octave and 1/3 octave band analysis
simultaneously. (In this case, the upper limit is 8 kHz for octave band and
12.5 kHz for 1/3 octave band.)
Measurement results are stored directly on a CompactFlash memory card
(called CF card in this manual).
Communication with a computer is possible via the built-in USB port. Be-
cause the USB port conforms to storage specications, the NA-28 will be
recognized as a removable disk when connected to a computer. This allows
transfer of data from the CF card to the computer without having to remove
the CF card from the NA-28.
The infrared remote control available as an option allows control of the
NA-28 without a cable link.
The comparator output is an open collector type, which can be used for
control of external equipment. Conversely, the trigger input allows control
of the NA-28 from another device.
Optional program cards for implementing waveform recording, architectural
acoustics measurements and FFT Analysis of measurement are also sup-
ported.

2
Outline
The Sound Level Meter NA-28 allows the following quantity measure-
ments.
Main processing (sound level meter mode, analyzer mode)
Simultaneous measurement of all items with selected time weighting and
frequency weighting characteristics
Sound level Lp
Equivalent continuous sound level Leq
Sound exposure level LE
Maximum sound level Lmax
Minimum sound level Lmin
Percentile sound level LN(1 to 99) 1-increment steps,
max. 5 values, calculated from
Lpor Leq,1sec
In sound level meter mode, one of the following measurements can be
selected for the sub channel.
Peak sound level Lpeak
Takt-max sound level Ltm5
Frequency weighting characteristics are the same as for the sub
channel.
Frequency weighting characteristics A, C, Z
Time weighting characteristics
(main channel) F, S, 10 ms
(sub channel) F, S, 10 ms, I
A color LCD with backlight shows measurement parameters and measure-
ment values in sound level meter mode and analyzer mode.
The following options are available separately, to further enhance the range
of applications for the product.
Level recorder LR-07, LR-20A (No CE)
For recording sound level changes over time.