az-instrument 8930 User manual

8930A, for 23.8mm diameter 8930B, for 13.2mm diameter
8930C, for 12.2mm diameter 8930D, for 7mm diameter

INTRODUCTION
1
This compact sound level calibrator is a
portable, battery operated sound source,
suitable for many portable sound level
meters. When a microphone from a sound
level meter is inserted into this calibrator,
the sound level meter picks up the signal
and displays the signal in dB (decibel) units.
The sound level meter should be adjusted
(if necessary) to match the calibrator's
output signal as closely as possible.
This calibrator provides a stable reference
level across changes in many environmental
conditions. Corrections for variations in
atmospheric pressure are not required.
The system emits the signal through the
microphone cavity. An outer capillary hole
balances the chamber static pressure
protecting microphones from overpressure
due to their insertion.
The generated sound pressure level is
equal to 94dB, 104dB and 114 dB at 1000 Hz
frequency. The 1000 Hz frequency allows
calibrating sound level meters with any
frequency weighting (LIN, A, B, ...), Wi thout
applying any correction factor. The generated
sound pressure level is independent of
atmospheric pressure, users don't need to
adjust the value according to static pressure
over a wide range of values.
It can be conveniently used both in laboratory
and in the field. The 114 dB sound level
allows performing calibrations even in high
background noise environments.
There are total 4 models allow calibrating
different size microphones with
mechanical dimensions compliant with
IEC 61094-1and IEC 61094-4.

Features:
Meet IEC 60942:2018, class 2 standard
Suitable for all sound level meter with
microphone head mechanical compliant
with IEC 61094-1 or IEC 61094-4,
such as 23.8/13.2/12.2 and 7mm
Calibration frequency at 1K Hz with
three level 114dB, 94dB and 104dB
Vivid LED display with stability and
low power indicator
Power up by batteries, easy to carry
around
MATERIAL SUPPLIED
Meter (check if the microphone
cavity diameter meets your need)
2pcs AA alkaline batteries
Operation manual
Hard carrying case
2
POWER SUPPLY
Regular or alkaline battery are both fine
to use in this calibrator.
A complete sound level calibrator
package contains of the following items.
There are total 4 models allow calibrating
different size microphones with
mechanical dimensions.
The battery compartment is in the rear
side of the detector. Open the battery
cover and install 2pcs AA size batteries
in correct polarity and in good contact.
The power LED turn into red color while
measured battery voltage is below 2.2V
. Please change 2pcs new AA batteries
to ensure accurate reading.

3
CAUTION
1. Before operation, leave the calibrator
in stable room temperature for at least
2 hours to make calibrator reach
temperature equilibrium.
2. Make sure the microphone and the
calibrator are correctly aligned during
insertion because the microphone
could be damaged if not inserted
squarely, or if inserted at speed or if
excessive force is used.
3. The calibrator need to be placed on a
flat surface. While measuring, you
should move neither the microphone
nor the calibrator; make sure that the
worktable doesn't transmit vibrations.
4. During calibration, if the environmental
conditions are not respected, such as
-Ambient noise is too large
-Shocks given involuntarily
Wait for the stabilization before resume
the calibration process.
5. This is a very precision instrument and
should be treated with care. Avoid below
and use hard carry case to store and
protect the instrument.
-Physical shocks or drops
-Ingress of dirt, dust and other foreign
objects into the sound cavity
-Exposure to water droplets or
condensation

OPERATION
POWER ON/OFF
5
Press power key briefly to turn on.
The green power and dB LED will flash
for 10 seconds till system warm up time
is completed. If the power LED turn into
red color, it means the power is too low
to operate correctly, please refer to
battery replacement section in page 2
to install new batteries.
Press power key again may turn it off
and remove the microphone from the
calibrator.
The meter switches off automatically
after 20 minutes of inactivity.
ADJUST DB VALUE
The calibrator is default as 94dB.
Press the dB toggle button to toggle
between the 94.0 dB, 104dB and
114dB Level.
Wait for 8 seconds for the output to
stabilize. You will see selected dB
green LED stop flashing to indicate the
system is stable
CHECK READING OF SLM
Refer to above Caution section in page
3 to ensure the calibrator is ready to use.
Carefully insert microphone up to the
stop within the calibrator cavity. The
O-ring will offer some resistance.
Check the detected value on sound
leveI meter display. If the sound level
meter does not match the calibrator's
signal (within specification), adjust it as
explained in manual of sound level
meters.

6
TROUBLESHOOTING
? DB LED keep flashing and running in
cycle and generated sound always
stay the same, no change. Why?
Root cause
Hardware error
Solution
Call for after sales service.
?Why power key is red LED?
Root cause
Battery power is too low to operate
Solution
Change or charge batteries.
? Instrument cannot be switched on.
Root cause
Batteries are depleted.
Solution
Change batteries.
SPECIFICATION
8930
Model
Calibration frequency
Humidity < 90%
60*130*37.5
2pcs AA Alkaline Batteries
Meter/Battery/Manual/paper box
~400g
Storage RH%
Dimension(mm)
Weight
Standard Package
Battery
LED indicator 1Green/Red: ready/low power 3 Green:114/104/94dB
Battery life time
25~ 90% RH
Operating RH%
Total distortion
1000Hz
50 hours typical
Stabilization time 10 Seconds
+/-0.4dB
<3%
Frequency accuracy +/-1.7%
Sound pressure level 94dB 104dB 114dB
Sound pressure accuracy
Ambient condition influence
Temperature and humidity influence : < 0. 4 dB @ 0…40 °C and 25…90%RH
Static pressure influence:< 0.1 dB @ 65…10 8 kPa
Stability levels
Short-term stability (<60s): ±0.15 dB
Stability after 1 year with normal use: ±0.35 dB
o
0~40 C
Operating temp.
o
-20~50 C
Storage temp.
Microphone head cavity
(dia.mm)
8930A
23.8mm
8930B
13.2mm
8930C
12.2mm
8930D
7mm

7
WARRANTY
The meter is warranted to be free from
defects in material and workmanship
for a period of one year from the date
of purchase. This warranty covers
normal operation and does not cover
misuse, abuse, alteration, neglect,
improper maintenance, or damage
resulting from leaking batteries. Proof
of purchase is required for warranty
repairs. Warranty is void if the meter
has been opened.
RETURN AUTHORIZATION
OTHER RELATED PRODUCTS
Authorization must be obtained from
the supplier before returning items for
any reason. When requiring a RA
(Return Authorization), please include
data regarding the defective reason,
the meters are to be returned along
with good packing to prevent any
damage in delivery and insured against
possible damage or loss.
Other sound level meter:
a.Model 8928 Portable digital sound level
meter, general purpose.
b.Model 8925 Portable digital sound level
meter, general purpose.
c.Model 8921 type II digital sound level
meter, accuracy measuring purpose.
c.Model 8922 type II digital sound level
meter, accuracy measuring purpose.

Accuracy, the Zenith of
Measuring / Testing Instruments !
More products available !
Hygrometer/Psychrometer
Thermometer
Anemometer
Sound Level Meter
Air Flow meter
Infrared Thermometer
K type Thermometer
K.J.T. type Thermometer
K.J.T.R.S.E. type Thermometer
pH Meter
Conductivity Meter
T.D.S. Meter
D.O. Meter
Saccharimeter
Manometer
Tacho Meter
Lux / Light Meter
Moisture Meter
Data logger
Temp./RH transmitter
Wireless Transmitter ..........
2020/6 V01