Lutron Electronics SL-4022 User manual

IEC 61672, class 1
SOUND LEVEL METER
Model : SL-4022
Your purchase of this
SOUND LEVEL METE
R
marks a step forward for
you into the field of
precision measurement.
Althou
g
h this METER is a
complex and delicate
instrument, its durable
structure will allow many
years of use if proper
operatin
g
techniques are
developed. Please read
the followin
g
instructions
carefully and always keep
this manual within easy
reach.
OPERATION MANUAL

TABLE OF CONTENTS
1. FEATURES...........................................................
.
1
2. SPECIFICATIONS..................................................1
3. FRONT PANEL DESCRIPTION................................
.
4
3-1 Electric condenser microphone.......................
.
4
3-2 Display.........................................................
.
4
3-3 Time Weighting ( Fast/Slow ) selector.............4
3-4 Max. hold & Instant display selector................4
3-5 Calibration VR (Accuracy adjust VR)................4
3-6 Reset button for Max. hold function................ 4
3-7 A/C weighting selector................................... 4
3-8 Signal output terminal....................................4
3-9 Range selector..............................................
.
4
3-10 Power off/On/Internal calibration selector.......4
3-11 Battery Compartment/Cover.......................... 4
3-12 Range upper/lower indicator..........................4
3-13 Microphone change installation
4. MEASURING PROCEDURE.....................................
.
5
5. MEASURING CONSIDERATION..............................
.
6
6. SIGNAL OUTPUT..................................................
.
7
7. REPLACEMENT OF BATTERY.................................
.
8
8. CALIBRATION .....................................................
.
8
9. FREQUENCY WEIGHTING CHARACTERISTICS
OF A & C NETWORKS...........................................
.
10
10.TIME WEIGHTING ( FAST & SLOW )
CHARACTERISTICS...............................................10

1. FEATURES
* Large LCD display, easy to read.
* Frequency weighting networks ( A & C weighting ) &
Time weighting ( Fast/Slow ) are designed to meet the
IEC 61672 Class 1.
* AC output for system expansion.
* Build in CALIBRATION VR on front panel.
* Changeable condenser microphone for high accuracy &
long-term stability.
* Max. Hold function for stored the maximum value on
display.
* Build max. hold reset switch.
* Warning indicator for over and under load.
* LCD display for low power consumption & clear
read-out even in bright ambient light condition.
* Used the durable, long-lasting components, including
a strong, light weight ABS-plastic housing case.
* Low battery indicator.
2. SPECIFICATIONS
Display 18 mm (0.7") LCD (Liquid Crystal Display),
3 1/2 digits.
Function dB (A & C frequency weighting),
Time weighting ( Fast, Slow),
Max. hold, AC output.
Measurement 3 ranges :
Range 30 - 70 dB, 60 - 100 dB, 90 - 130 dB
Resolution 0.1 dB.
1

Accuracy Frequency weighting ( 31.5 Hz to 16 KHz )
(23± 5 )℃ meet IEC 61672 Class 1, calibrating input
signal on 94 dB, then the accuracy of A/C
weighting is specified as following :
31.5 Hz - ± 2.0 dB, 63 Hz - ± 1.5 dB,
125 Hz - ± 1.5 dB 250 Hz - ± 1.4 dB,
500 Hz - ± 1.4 dB, 1 KHz - ± 1.1 dB
2 KHz - ± 1.6 dB, 4 KHz - ± 1.6 dB,
8 KHz - + 2.1 dB to -3.1 dB,
12.5 KHz - + 3.0 dB to -6.0 dB,
16 KHz - + 3.5 dB to -17.0 dB.
Characteristics of A & C.
A weighting :
The characteristic is simulated as "Human
Frequency Ear Listing" response. Typical, if making
Weighting the environmental sound level measurement,
Network always select to A weighting.
C weighting
The characteristic is near the "FLAT"
response. Typical, it is suitable for
checking the noise of machinery (Q.C.
check) & knowing the sound pressure level of
the tested equipment.
Frequency 31.5 Hz to 16.0 KHz.
Calibrator B & K (Bruel & Kjaer) :
Multi-fuction acoustic calibrator,
model : 4226.
Microphone Electric condenser microphone.
Size of 0.5 inch standard size.
Microphone
Range 30 to 70 dB, 60 to 100 dB, 90 to 130 dB,
Selector 40 dB on each step, with over & under
range indicating.
2

Time Fast - t= 200 ms, Slow - t = 500 ms,
Weighting * "Fast" range is simulated the
(Fast & Slow) human ear response time.
* "Slow" range is easy to get the avg.
values of vibration sound level.
* The "Fast" & "Slow" response
range are designed to meet IEC 61672
Class 1 requirement.
Calibration * Build in external calibration VR on front
panel.
* Calibrated via external SOUND
CALIBRATOR.
* Calibrated via internal 94 dB/1 KHz
generator.
Output Signal AC output - AC 750 mVrms corresponding to
each range step.
Output 3.5 mm Dia. phone output terminal is
Terminal provided for connection with analyzer,
level recorder, tape recorder.
Operating 0 to 50 ( 32 to 122 ).℃℃℉ ℉
Temperature
Operating Less than 80% RH.
Humidity
Power Supply DC 9V battery x 2 PCs, 006P, MN1604 ( PP3 )
or equivalent, heavy duty or alkaline type.
Power Approx. DC 17 mA.
Consumption
Weight 450 g/0.99 LB .
Dimension 260 x 87 x 36 mm ( 10.2 x 3.4 x 1.4 inch).
Standard Instruction Manual ................. 1 PC.
Accessories Calibration screw driver........... 1 PC.
Hard carrying case ( CA-06 ).... 1 PC.
Optional 94 dB Sound Calibrator, model : SC-941.
Accessories 94/114 dB Sound Calibrator,
model : SC-942.
3

3. FRONT PANEL DESCRIPTION
Fig. 1
3-1 Electric condenser microphone
3-2 Display
3-3 Time Weighting ( Fast/Slow ) selector
3-4 Max. hold & Instant display selector
3-5 Calibration VR (Accuracy adjust VR)
3-6 Reset button for Max. hold function
3-7 A/C weighting selector
3-8 Signal output terminal
3-9 Range selector
3-10 Power off/On/Internal calibration selector
3-11 Battery Compartment/Cover
3-12 Range upper/lower indicator
3-13 Microphone change installation
4

4. MEASURING PROCEDURE
1)Slide the " Power off/On selector " ( 3-10, Fig 1 )
to the " On " position.
0 = Off, 1 = On
2)For the instant display reading, slide the " Max. hold
& Instant display selector " ( 3-4, Fig. 1 ) to the "
Instant " position. General application always select
the " Instant " function. For the " Max. hold " function,
please refer the 4-7, page 6.
3)Slide the A/C weighting selector ( 3-7, Fig. 1 ) to
"A" or "C" position for sound level measuring.
NOTE :
a. The characteristic table of A, C weighting,
please ref. page 9.
b. The characteristic of A weighting is simulated
as the "Human Ear Listening" response.
Typically, if making the environmental sound
level measurement, always select the A
weighting typically.
c. The C weighting characteristic is near the
"FLAT" response. Typically, it is suitable for
checking the noise of machinery (Q.C. check)
& knowing the real sound level of the tested
equipment.
4)Determine proper measuring range by selecting
the " Range selector " ( 3-9, Fig. 1 ) to minimize the
tolerance of readout. When left corner of LCD
show " " indicator, ( 3-12, Fig. 1 ), it shows the▲
dB range selection is upper or lower setting. Slide
range selector to other range for measuring.
5

5)According on various measuring sound source,
select the " Time weighting selector " ( 3-3, Fig. 1 )
to " F " or " S " position.
Typically select the " Time weighting selector " to
" F " position.
6)Hold the instrument in hand and point the
microphone at measured noise source, the sound
level will be displayed on "dB" ( decibel) unit.
7)Max. hold
During the sound level measurement, if intend to
hold the maximum ( peak ) value on display, slide
" Max. hold & Instant display selector " ( 3-4, Fig. 1 )
to the " Max. hold " position.
Note :
a. During the operation of " Max. hold function ",
push " Reset button for Max. hold function " ( 3-6,
Fig. 1 ) once a while will reset the max. peak value.
b. If not use the " Max. hold " function, it should
select the " Max. hold & Instant display selector "
( 3-4, Fig. 1 ) to the " Instant " position.
5. MEASURING CONSIDERATION
1)Please should select the proper weighting selector (A
weighting or C weighting). The A weighting selector will
be engaged normally.
2)Please select proper measurements range to minimize
the tolerance of readout.
6

3)Please don't keep or operate the instrument at
high temperature & humidity environment for a
long period.
4)Keep microphone dry & avoid serious vibration.
5)For general application of sound dB measurement,
we recommend select the panel switch to the
following position :
3-3 Time Weighting ( Fast/Slow ) selector
Select to " F "
3-4 Max. hold & Instant display selector
Select to " Instant "
3-7 A/C weighting selector
Select to " A weighting "
3-9 Range selector
Select to " 30 - 70 dB " or " 60 - 100 dB ".
3-10 Power off/On/Internal calibration selector
Select to " 1 " ( On ).
6. SIGNAL OUTPUT
1)The instrument is provided an 3.5 mm Dia. " Phone signal
output terminal " ( 3-7, Fig. 1 ) for connecting with
analyzer, level recorder, tape recorder, controller
...etc.
2)Output Signal :
AC output - AC 750 mVrms corresponding to each range
step.
7

7. REPLACEMENT OF BATTERY
1)When the left corner of LCD display show " BAT ", it is
necessary to replace the battery. However, in-spec.
measurement may still be made for several hours after "
Low battery indicator " appears before the instrument
become inaccurate.
2)Slide the " Battery Cover " ( 3-11, Fig. 1 ) & take the
battery away from the battery compartment..
3
)
Replace with 2 PCs 9V battery ( heavy duty type ) and
reinstate the cover.
8. CALIBRATION
The sound level meter is built in the internal calibration
" Calibration VR " ( 3-5, Fig. 1 ) on the front
panel. Please according the following procedures to
calibrate the instrument accurately, if it is necessary.
8-1 Calibrated via external SOUND CALIBRATOR
1
)
Prepare the optional " SOUND CALIBRATOR ", such as
" SC-941 " or " SC-942 ". Power on the Sound
Calibrator & plug calibrator output into the " Electric
condenser microphone " head ( 3-1, Fig. 1 ) of the
Sound Level Meter.
2)Slide the " Range selector " ( 3-9, Fig. 1 ) to " 60 - 100
dB " position.
3)Slide " Time Weighting selector " ( 3-3, Fig. 1 ) to
" F " position.
8

4)Slide the " A/C weighting selector " ( 3-7, Fig. 1 )
to " A weighting " position.
5)Carefully adjust the " Calibration VR " ( 3-5, Fig. 1 )
with " - " screw driver (include accessory ), until the
display read within " 94.0 ± 0.2 " dB.
8-2 Calibrated via internal 94 dB generator The
sound level meter is built in the internal standard 94 dB/1
KHz square wave generator for the purpose to calibrate
come certain amplifier circuit ( not the complete meter
system ). Please according the following procedures to
calibrate the instrument before making operation, if the
instrument not in use for a long time. The calibration
method are similar as above 8-1, but not connect the
external sound calibrator ( SC-941, SC-942... ), the
other should slide " Power off/On/Internal calibration
selector " ( 3-10 , Fig. 1 ) to the " CAL. " position "
Carefully adjust the " Calibration VR " ( 3-5, Fig. 1 )
with " - " screw driver ( included accessory ), until the
display read within " 94.0 0.2 " dB.
Note :
If intend to make calibration
accurately of whole meter, it is
recommended to use the calibrating
procedures of above 8-1 " Calibrated via
external SOUND CALIBRATOR "
9

9. FREQUENCY WEIGHTING
CHARACTERISTICS OF A & C
NETWORKS
Frequency A Weighting C Weighting Tolerance
Charac. Charac. ( IEC 61672
Class 1 )
31.5 Hz -39.4 dB -3 dB ± 2.0 dB
63 Hz -26.2 dB -0.8 dB ± 1.5 dB
125 Hz -16.1 dB -0.2 dB ± 1.5 dB
250 Hz -8.6 dB 0 dB ± 1.4 dB
500 Hz -3.2 dB 0 dB ± 1.4 dB
1 KHz 0 dB 0 dB ± 1.1 dB
2 KHz +1.2 dB -0.2 dB ± 1.6 dB
4 KHz +1 dB -0.8 dB ± 1.6 dB
8 KHz -1.1 dB -3 dB +2.1 dB
-3.1 dB
12.5 KHz -4.3 dB -6.2 dB +3.0 dB
-6.0 dB
16 KHz -6.6 dB -8.5 dB +3.5 dB
-17.0 dB
10. TIME WEIGHTING (FAST & SLOW)
CHARACTERISTICS
T
ime Weighting Max. response Tolerance
Charac. ref. continuous ( IEC 61672 Class 1 )
signal
F ( Fast ) - 1.0 dB + 1.0 dB,
S ( Slow ) - 4.1 dB ± 1.0 dB
* Test under signal on 1,000 Hz/94 dB.
10
0703-SL-4022