Rion NC-75 User manual

3-20-41 Higashimotomachi, Kokubunji, Tokyo 185-8533, Japan
http://www.rion.co.jp/english/
INSTRUCTION MANUAL
Sound Calibrator
NC-75

i
Organization of this manual
This manual describes the features and operation principles of the sound calibrator
NC-75.
The contents of this instruction manual is based on IEC 60942:2003.
The following pages contain important information on safety. Be sure to read this part.
This manual contains the following sections.
Outline
Gives basic information on the unit.
JCSS
Describes about JCSS calibration.
Controls and Features
Briey identies and explains all parts of the unit.

ii
* All company names and product names mentioned in this manual are
trademarks or registered trademarks of their respective owners.
Preparations
Describes how to insert batteries and use the adapter.
Calibration
Describes the basic steps and procedures for calibration.
Reference
Describes the calibration values for sound level meter and analyzer. Also
describes effects of exposure to radiofrequency elds.
Specications
Lists the technical specications of the unit

iii
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.
The product described in this manual is in conformity with the
following European standards;
EN60942:2003 EN61326-1:2013
This product can be used in any areas including residential areas.

iv
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.
Mentioned about the tips to
use this unit properly. (This
messages do not have to do
with safety.)
Note
Important
Disregarding instructions
printed here incurs the risk of
damage to the product.

v
Precautions
Operate the unit only as described in this manual.
Do not use or store the unit in locations which may be
- subject to splashes of water
- subject to high levels of dust
- subject to direct sunlight
- subject to vibrations or shock
- subject to adverse effects from salinity, sulfur content, oils, chemicals,
gases etc.
- outside of the specied temperature and humidity range
- subject to drastic temperature changes and to condensation
To reduce the risk of inadvertent damage from water, dust, vibrations,
shocks etc., it is recommended to perform calibration with the unit placed
in its soft case NC-75-011.

vi
When not using the unit, it is recommended to leave the unit in the soft
case NC-75-011 and just close the lid.
Store the unit in the desiccator in locations subject to high temperatures
and high humidity.
Do not use the unit for any purpose other than calibrating sound level
meters or microphones.
Do not hold the active coupler to the ear for a long time.
Be sure to use only the specied batteries.
Remove the batteries from the unit if it is not to be used.
Do not try to disassemble or alter the unit.
Never insert any foreign object into the coupler.
If the unit will be carried around and there is a risk that it may be dropped,
it is recommended to attach the supplied hand strap VM-63-017 using the
strap hole. You can then wrap the strap VM-63-017 around your wrist
when carrying the unit.

vii
When using the unit near rotating machinery, take care the strap VM-63-017
cannot be caught in the machinery.
In case of malfunction, do not attempt any repairs. Note the condition of
the unit clearly and contact the supplier.
Dispose of the unit and of used batteries in accordance with local laws
and regulations. The unit does not contain any substances harmful to the
environment. Treat the unit as non-combustible waste.
I n order to maintain continued precision, have the unit checked and serviced
once per year. Contact the supplier.
To clean the unit, use only a dry cloth or a cloth lightly moistened with
lukewarm water. Do not use solvents or alcohol-based cleaners.
When mounting and dismounting the microphone and sound calibrator,
do not rotate the sound level meter or sound calibrator. Otherwise the
protective grid of the microphone may become loose or detached, causing
damage to the microphone diaphragm.

viii
Be sure to use only the 1/2-inch microphone adapter NC-75-022 and
1/4-inch microphone adapter NC-75-S11 designed specically for the
NC-75. Using another adapter may prevent correct calibration.

ix
Contents
FOR SAFETY................................................................................iv
Outline............................................................................................1
JCSS calibration..............................................................................2
Controls and features ......................................................................3
Preparations ....................................................................................6
Inserting the batteries ................................................................6
Using the 1/2-inch microphone adapter NC-75-022 and
the 1/4-inch microphone adapter NC-75-S11 ..............................8
Attaching the hand strap VM-63-017.......................................10
Using the soft case NC-75-011 .................................................11
Calibration ....................................................................................12

x
Reference ......................................................................................17
Sound level meter and analyzer calibration value..................... 17
Sealing mechanism..................................................................21
Electromagnetic compatibility .................................................23
Specications ................................................................................27

1
Outline
The NC-75 is a 1 kHz, 94 dB sound calibrator conforming with JIS C 1515:2004
Class 1 (IEC 60942:2003 class 1) specications. While being compact, lightweight,
and easy to use, the unit meets the performance requirements for calibrating precision
sound level meters.
A reference microphone is integrated in the unit, which eliminates the need to
compensate for differences in calibration sound pressure level caused by differences
in the equivalent volume of various microphones. 1-inch, 1/2-inch, and 1/4-inch
microphones made by Rion as well as microphones made by other manufacturers
that meet the IEC 61094-4 size specications are supported for calibration.

2
JCSS calibration
The sound calibrator NC-75 has undergone full JCSS calibration and provides
traceability according to the requirements of the Japan Measurement Act, Article
134 for Specied Standard Instruments (National Measurement Standard). This
means that calibration results obtained with this sound calibrator have credibility
on the national level. The JCSS Calibration Certicate supplied with this product
is proof of this fact. JCSS is operated by an accreditation body (IA Japan) which is
a signatory to the Asia Pacic Laboratory Accreditation Cooperation (APLAC) as
well as the International Laboratory Accreditation Cooperation (ILAC) in an MRA
(Mutual Recognition Arrangement). Calibration certicates bearing the ILAC MRA
compliant JCSS symbol are recognized by countries throughout the world that are
APLAC or ILAC signatories.

3
Controls and features
LED
1/2-inch microphone adapter
NC-75-022
1/4-inch microphone adapter
NC-75-S11(option)
Strap hole
Battery cover
Case
Coupler
Power switch
Rear panel
Soft case
NC-75-011
Hand strap VM-63-017

4
Controls and Features
Coupler
The microphone to be calibrated is inserted here.
Battery cover
Separate from the case by simultaneously pressing the two sections marked
PUSH. (See illustration on page 6.)
Case
Two batteries (Alkaline batteries LR6 or Ni-MH secondary batteries) are
inserted here.
LED
Lights up when the power switch is set to ON.
Power switch
Serves to turn the unit on and off.
1/2-inch microphone adapter NC-75-022
Use this adapter when the outer diameter of the microphone is 1/2 inch.

5
Controls and Features
1/4-inch microphone adapter NC-75-S11(option)
Use this adapter together with the 1/2-inch microphone adapter NC-75-022
for microphones with an outer diameter of 1/4 inch.
Hand strap VM-63-017
Attaching this strap to the strap hole and wrapping the strap around the
wrist when carrying the NC-75 reduces the risk of dropping the unit.
Strap hole
Use this hole to install the supplied strap VM-63-017.
Soft case NC-75-011
This case is designed to protect the unit and reduce the risk of damage
from water, dust, vibrations, shocks etc.

6
Preparations
Inserting the batteries
1. Open the case by pressing the sections marked PUSH and pulling
the battery cover off the case.
PUSH
Press the PUSH sections on
both side and open the case.

7
Preparations
2. Insert two batteries
(Alkaline batteries LR6
or Ni-MH secondary
batteries) with correct
polarity.
3. Snap the battery cover onto the case again.
Important
-Before inserting the batteries, check the
correct + and − orientation as shown above.
The polarity is also marked inside the battery
wells.
-Do not mix old and new batteries.
-Do not mix different types of batteries.
-Always remove the batteries when not using
the unit.
-Dispose of used batteries in accordance with
local laws and regulations.

8
Preparations
Using the 1/2-inch microphone adapter NC-75-022 and
the 1/4-inch microphone adapter NC-75-S11
1/2-inch microphone
adapter NC-75-022
1/4-inch microphone adapter
NC-75-S11(option)
1/2-inch
microphone
adapter
NC-75-022
If the outer diameter of the microphone is 1 inch, remove the 1/2-inch microphone
adapter and the 1/4-inch microphone adapter.
If the diameter is 1/2 inch, use the 1/2-inch microphone adapter NC-75-022.
If the diameter is 1/4 inch, use the 1/2-inch microphone adapter NC-75-022
and the 1/4-inch microphone adapter NC-75-S11 together.