Rion NL-42A User manual

3-20-41 Higashimotomachi, Kokubunji, Tokyo 185-8533, Japan
https://www.rion.co.jp/english/
INSTRUCTION MANUAL
Sound Level Meter
NL-42A / NL-52A

i
Organization of the NL-42A/NL-52A documentation
Documentation for the Sound Level Meter NL-42A/NL-52A comes in three
parts, as listed below.
Instruction Manual (this document)
Describes operating procedures for the NL-42A/NL-52A, connection and
use of peripheral equipment such as a level recorder and printer, and use
of the SD memory card.
Serial Interface Manual
Describes communication with a computer, using the serial interface built
into the NL-42A/NL-52A. 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.
The current instruction manual is available on our website.
(https://www.rion.co.jp/english/)
* 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 NL-42A/
NL-52A. If the unit is used together with other equipment to congure a mea-
surement system, consult the documentation of all other components as well.
Pages v and following 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.
Reading the Display
Explains symbols and other information shown on the display of the unit.
Measurement
Explains the basic procedures for measurement.
Card capacity and store time
Lists the data store time corresponding to the SD memory card capacity, etc.
Store Operation
Explains how to store measurement data.

iv
Input/Output Connectors
Explains the input and output connectors of the unit.
Default Settings
Lists the factory default settings of the unit.
Setup Files
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 damage to
the unit.
Additional information about
using the unit. (These notes do
not directly affect safety.)
Note
WARNING Disregarding instructions printed
here incurs the risk of death or
severe injury to persons.
Disregarding instructions printed
here incurs the risk of injury to
persons and/or damage to periph-
eral equipment.

vi

vii
Quantier Notation
(Sound level and sound pressure level are expressed uniformly as sound
pressure level, distinguished by the use of frequency weighting.)
Measurement value
The time weighting characteristics
F, S I
Lp
Sound pressure
level
A-weighted sound pressure level LAF, LAS LAI
C-weighted sound pressure level LCF, LCS (LCI)
Z-weighted sound pressure level LZF, LZS (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 LAImax
Maximum C-weighted sound level LCFmax, LCSmax (LCImax)
Maximum Z-weighted sound level LZFmax, LZSmax (LZImax)
LN
Percentile sound
level
Percentile A-weighted sound level LAFNn, LASNn(LAINn)
Percentile C-weighted sound level LCFNn, LCSNn(LCINn)
Percentile Z-weighted sound level LZFNn, LZSNn(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 an existing at-weighted level.
• The combination of peak sound level and takt-max with I character-
istics does not exist.
• Generally, measurement value shown in brackets ( ) are not used or
not suitable for evaluation.

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