Digital Measurement Metrology 8926 User manual

Model: 8926
INSTRUCTION MANUAL
Analog Sound Level
Meter
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1-866-960-9400
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Digital Measurement Metrology, Inc
TM

1
CONTROLS and INDICATORS
-6
-2
+2
+4
+6
0
-4
Good
OFF
BAT
120dB
110dB
100dB
90dB
80dB 70dB 60dB
SOUND LEVEL METER
MAX
ASF
C
1
2
10
3
4
5
6
7
8
9
1. Microphone
2. OFF / Range Selector
3. Max Hold button
4. A /C weighting selector
5. dB indicating scale
6. Fast / Slow selector
7. Cal.(Calibration) Adjustment ( side )
8. Output Jack ( side )
9. Battery Cover ( Rear )
10. Tri-pod mount ( Rear )
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Digital Measurement Metrology, Inc
TM

2
The Analog Sound Level Meter is a
versatile device which measures sound
level in any acoustic environment. The
meter will enable you to easily measure
sound or noise levels that are loud or soft,
high or low-pitched, broadband, intermittent,
or in factories, schools, offices, airports,
sound studios, theaters, auditoriums,
automobiles, and in the home. This
precisely calibrated meter features a large,
easy-to-ready analog indicator and is
battery powered for convenient, portable
use.
INTRODUCTION
IMPORTANT NOTE
Continuous high pressure levels (>
100 dB) can permanently damage your
ears. Always set the volume accordingly
when testing. Continuous high pressure
levels can permanently damage your
loudspeakers.
Remember noise levels above 85 dB will
harm hearing over time. Noise levels
above 140dB can cause damage to
hearing after just one exposure.
The meter is calibrated before ex-factory
,using a standard accoustic calibrator
which generate "94dB" output .
We would recommend you to re-calibrate
the meter with a cycle one year .
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1-866-960-9400
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Digital Measurement Metrology, Inc
TM

Points of Reference measured in dBA or
decibels :
0 The softest sound a person can
hear with normal hearing
10 normal breathing
20 whispering at 5 feet
30 soft whisper
50 rainfall
60 normal conversation
110 shouting in ear
120 thunder
NOISE LEVELS IN
ENVIRONMENT FACT SHEET
HOME
50 refrigerator
50 - 60 electric toothbrush
50 - 75 washing machine
50 - 75 air conditioner
50 - 80 electric shaver
55 coffee percolator
55 - 70 dishwasher
60 sewing machine
60 - 85 vacuum cleaner
60 - 95 hair dryer
65 - 80 alarm clock
70 TV audio
70 - 80 coffee grinder
70 - 95 garbage disposal
75 - 85 flush toilet
80 pop-up toaster
80 doorbell
80 ringing telephone
80 whistling kettle
80 - 90 food mixer or processor
80 - 90 blender
80 - 95 garbage disposal
110 baby crying
110 squeaky toy held close to the ear
3
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RECREATION
40 quiet residential area
70 freeway traffic
85 heavy traffic, noisy restaurant
90 truck, shouted conversation
95 - 110 motorcycle
100 snowmobile
100 school dance, boom box
110 disco
110 busy video arcade
110 symphony concert
110 car horn
110 -120 rock concert
112 personal cassette player on high
117 football game (stadium)
120 band concert
125 auto stereo (factory installed)
WORK
40 quiet office, library
50 large office
65 - 95 power lawn mower
80 manual machine, tools
85 handsaw
90 tractor
90 - 115 subway
95 electric drill
100 factory machinery
100 woodworking class
105 snow blower
110 power saw
110 leafblower
120 chain saw, hammer on nail
120 pneumatic drills, heavy machine
120 jet plane (at ramp)
120 ambulance siren
125 chain saw
4
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Digital Measurement Metrology, Inc
TM

5
SPECIFICATION
Ranges:
Range Setting (Usable range):
60dB (54 to 66), 70dB (64 to 76),
80dB (74 to 86), 90dB (84 to 96).
l00dB (94 to 106), II0dB (104
to 116), 120dB (114 to 126)
Resolution: Analog Continuous
Accuracy: 3 dB at 94 dB sound
level at lkHz
Frequency weighting: A and C
Meter response: Fast and Slow
Microphone type: Electret
Condenser
Analog output: AC: 0.707Vrms
Power: Meter powered by 9V
battery ;120 hour battery
life
Dimensions/Weight: 2.7x7.1x1.4"
(68 x 180 x 36mm) / 5.1 oz. (160g)
54 to126dB in 7 ranges
referenced to 0.00002
ubar
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Digital Measurement Metrology, Inc
TM

WEIGHTING A / C
When the A/C Weighting Switch is set to
A, the meter primarily measures frequencies
in the 500 to 10000 Hz range, which is
the area of greatest sensitivity to the
human ear. When set to C Weighting, the
meter measures uniformly over the
frequency range of 32 to 10000 Hz, giving
an overall sound level indication.
METER OPERATION
6
OFF
BAT
120dB
110dB
100dB
90dB
80dB 70dB 60dB
MAX
ASF
C
A-weighting takes into account the
typical human ear response, reducing
the frequency response of the SPL
meter to the 500 - 10,000 Hz range,
where our ears are mostly sensitive.
B-weighting measures the whole range
from 32 to 10,000 Hz.
or HiFi-measuring
purposes, we would suggest to use the
wider set up.
C-weighting is f
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Digital Measurement Metrology, Inc
TM

FAST (F) AND SLOW (S)
RESPONSE
The S and F Switch sets the meter's
response time.
In the Slow position, the measurement
is damped and indicates an average
sound level. The Slow response in
most commonly used for workplace
and environmental noise studies.
In the Fast position, the meter reacts
rapidly to any change in the sound level.
Set the meter to "F" if the noise to be
measured consists of short bursts, or
if peak values are to be observed.
MAX HOLD
Maximum Hold permits the user to
freeze the meter's maximum reading
by locking the pointer at the sound
level peak. Hold down the MAX.
button to activate MAX. Hold. Release
the button for normal operation.
To measure a peak sound level , set the
F/S switch to F(Fast), and make sure of
the MAX button .
7
OFF
BAT
120dB
110dB
100dB
90dB
80dB 70dB 60dB
MAX
ASF
C
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1-866-960-9400
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Digital Measurement Metrology, Inc
TM

SETTING THE RANGE
There are seven setting range from
60dB, 70dB, 80dB, 90dB,100dB,110dB
to 120dB , start with the highest range
setting (120 dB) and work downward in
range using the Rotary Switch until there
is significant deflection of the meter's
pointer. See an example setting range
select from 60dB to 120dB .
MAKING A MEASUREMENT
First , set the F/S switch , then next set
the A/C switch , set the range switch as
above , start with the greatest range
setting of 120dB if you are not sure the
sound level range , then decrease the
range step by step , until the meter
pointer is comfortably within a particular
range.
For example , if the range switch is set
to 90dB , and the meter pointer indicates
-2dB ,then SPL is 90-2=88dB .
8
OFF
BAT
120dB
110dB
100dB
90dB
80dB 70dB 60dB
MAX
ASF
C
OFF
BAT
120dB
110dB
100dB
90dB
80dB 70dB 60dB
MAX
ASF
C
-6
-2
+2
+4
+6
0
-4
Good
SOUND LEVEL METER
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1-866-960-9400
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Digital Measurement Metrology, Inc
TM

LOW BATTERY INDICATION
Place the Rotary Select switch to the
'BAT' position and observe the analog
pointer for status of the battery voltage.
When you see the analog pointer
located on "GOOD" in green area , it
means the battery power is good ,
when you see the pointer located at
the red mark area , it indicates a weak
battery, replace with a good battery .
Remove power to the meter whenever
it is not being used to preserve battery
life.
-6
-2
+2
+4
+6
0
-4
Good
SOUND LEVEL METER
-6
-2
+2
+4
+6
0
-4
Good
SOUND LEVEL METER
OFF
BAT
120dB
110dB
100dB
90dB
80dB 70dB 60dB
MAX
ASF
C
Power is good
Power is weak
9
Always handle the meter carefully, do not
hold the meter directly between you and
the sound sources, as this might produce
an error of several decibels in the fre-
quency range above 100Hz . Position
the meter so an imaginary line between
you and the meter is perpendicular to a
line between the meter and the sound
source . To get the most accurate read-
ings , point the microphone toward the
sound source when possible .
www.dmm.ca
1-866-960-9400
PRECISION IS OUR VISION
Digital Measurement Metrology, Inc
TM

REPLACE BATTERY
Always remove power to the instrument
whenever it is not being used to preserve
battery life.
The meter supplied with a 9 volt battery,
to replace with a new battery ,first lay the
meter facedown on a clean ,flat surface.
Remove the battery cover by using a
screwdriver , observe polarity and replace
a new battery , then close the battery
cover by screwdrive.
TRIPOD MOUNTABLE
You can mount the meter on a camera
tripod with standard thread to reduce
hand noise and minimize the effects of
sound reflected from your body. This is
an auxiliary testing equipment .
Tri-pod mount
position
10
Battery compartmeny
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1-866-960-9400
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Digital Measurement Metrology, Inc
TM

11
WARRANTY
The meter is warranted to be free from
defects in material and workmanship for
a period of one years from the date of
purchase.
This warranty covers normal operation
and does not cover batteries,misuse,
abuse, alteration, tampering, neglect,
improper maintenance, or damage
resulting from leaking batteries.
Proof of purchase is required for
warranty repairs.
RETURN AUTHORIZATION
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
shipment and insured against possible
damage or loss .
A phono-type output jack is provided
on the meter for connection to external
test equipment. It outputs an AC
voltage (0.707V RMS maximum),
which is a linearized representation of
the analog scale reading.
Connect this output jack to a datalogger
,chart recorder, etc. for logging
purposes.
ALALOG OUTPUT
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Digital Measurement Metrology, Inc
TM