Extech Instruments 407764 User manual

User's Manual
EXTECH
:iMSTRUMEMTS
Datalogging Sound Level Meter
Model 407764
Range; 30dB to 130dB
4-digit LCD Display with 0.1 dB resolution
A and C Frequency Weighting
RS-232 PC Interface with
16,000 point datalogger and
Date / Time Stamp
Auto-Ranging
SLOW
A/C
MAS
Introduction
Congratulations on your purchase of Extech's Datalogging Sound Level Meter. The meter Is
capable of performing all your noise measurements needs in addition to it's capabilities for data
acquisition (direct data storage to a PC) or datalogging (data storage to Internal memory for
later download). Data storage enables the user to save data, analyze data and generate
reports. This professional meter, with proper care, will provide years of safe reliable service.

Specifications
Applicable Standards
Accuracy
Frequency range
Measuring level
Frequency weighting
Microphone
Display
Bargraph
Sampling rate
Memory size
Datalogging sample rate
Time weighting
MAX
Level ranges
Auto range
Linearity range
Alarm function
AC output
DC output
Power supply
Battery life
AC adapter
Operating temperature
Operating humidity
Storage temperature
Storage humidity
Memory size
RS-232 Interface
Dimensions
Weight
Accessories
IEC651 Type 2, ANSI 81.4 Type 2
±1.5dB (under reference conditions)
31.5Hz-8KHz
30- 130dB
A and C
0.5" Electret condenser microphone
4-digit LCD
Resolution: 0.1 dB
Display period: 0.5 sec.
50dB scale (1dB steps). Display period: 50mS; Auto-ranging:
10OdB scale, 2dB steps
50mS
16,000 records / 255 sets (non-volatile memory)
1 to 86,400 seconds per record
FAST: 125mS, SLOW: 1 sec.
Maximum reading held
30-80dB, 40-90dB, 50-1 OOdB, 60-110 dB, 70-120dB, 80-130dB
(Total of 6 ranges)
30to130dB
50dB
OVER indicator for readings higher than high limit.
UNDER indicator for readings lower than low limit.
0.707 Vrms at Full Scale
Output impedance approx. 6000
lOmV/dB
Output impedance approx. 1000
Four 1.5V 'AA' batteries
Approx. 30 hrs continuous operation
Voltage: 6VDC
Voltage Ripple: < lOOmVpp
Supply Current: > lOOmADC
Socket: Pin Ground
Casing: Positive
External Diameter: 3.5mm
32 to 104°F (0 to 40°C)
10to80%RH
14 to 140°F (-10 to 60°C)
10to80%RH
16,000 data records with Date and Time Stamping
Baud rate: 9600bps
10.4 X 2^ x 1.4" (265 x 72 x 35mm
Approx. 11.5 oz. (358g) including battery
Batteries, carrying case, screwdriver, windscreen, 3.5mm plug, RS-232
cable Id 2^n gender changer, Windows™ ccnrpatible software.
Safety symbols
CE
Meter is protected throughout by double insulation or reinforced
insulation.
Complies with EMC
Model 407764 Version 1.3 October 2001

Meter Description
B
1. Microphone
2. Display
3. Power switch
4. Level range control switch
5. MAX hold switch
6. Frequency weighting switch
7. Response time select switch
8. AC output terminal
9. DC output terminal
10. CAL (calibration) pot.
11. Extemal DC 6V power
12. RS-232 interface connector
13. Battery cover
14. Tripod mounting screw
15. Wind-screen
(Figure 1)
sue me ma
to-im
RS-232
V-
' '
-J
Display Description
1. Range selection
2. Date information
3. SPL; Instantaneous sound pressure level
4. Low-Battery
5. MAX: Maximum SPL value is held
6. Data recording
7. Measurement value
8. Memory full
9. Units ,
10. Frequency weighting (A/C)
11. TIME function
12. 50dB level (Bargraph)
13. Over range
14. SLOW time response
15. FAST time response
16. Under range
-8S
© (0 ©
11 SI
i§
c
d
(Figure 2)
>001
Model 407764 Version 1.3 October 2001

Measurement Preparation
• Read the following safety information before attempting to operate the meter
• Use the meter only as specified or the meter's built-in protection may be impaired.
Maintenance & Cleaning
• Service not covered in this manual should be performed by qualified personnel
• Periodically wipe the case with a dry cloth. Do not use abrasives or solvents.
Battery Replacement
When the battery voltage drops to a critical level, the £3 symbol appears on the LCD.
Replace batteries as soon as possible after the battery symbol appears. The batteries (4 AA)
are located in the rear battery compartment. Remove the single Philips head screw (center
rear) for access to the batteries.
Measurements
Default Configuration
1. The meter's default configuration is as follows: 40 to 90dB, 'A' Frequency Weighting, and
'FAST' Response Time
2. The LCD will reflect the meter's configuration.
Measurement Considerations
3. Use a windscreen to cover the miaophone in windy conditions.
4. Calibrate the meter often, especially if the meter has not been used for a long time.
5. Do not store/operate the meter in high temperature/humidity for long periods of time.
6. Keep the meter and the microphone dry.
7. Avoid severe vibration when using the meter.
8. Remove the battery when the meter will be stored for long periods of time.
Frequency Weighting
Change the Frequency Weighting by pressing the 'A/C button. The 'A' or 'C icon will display
on the right-hand area of the LCD.
Note: With 'A' weighting selected, the meter responds like the human ear (boosting and
cutting the noise amplitude over the frequency spectrum - see Appendix). 'A' weighting is
used for environmental measurements, OSHA regulatory testing, law enforcement, and
workplace design. Select 'C weighting for flat response measurements (no boost or cut). 'C
weighting is suitable for the sound level analysis of machines, engines, etc. Most OSHA
related testing is performed using 'A' Weighting and SLOW Response Time settings.
Response Time
Change the Response Time by pressing the 'FAST/SLOW' button. The 'FAST or 'SLOW'
icon will display on the upper area of the LCD.
Note: Select FAST to capture noise peaks and noises that occur ve|y quickly. In FAST mode,
the meter responds in 200ms. Select the SLOW Mode (meter responds in 500ms) to monitor
a sound source that has a reasonably consistent noise level or to average quickly changing
levels. Selection of Fast or Slow is determined by the application and any directives or
standards related to that application.
Auto/Manual Range
Press the LEVEL button up arrdW to scroll through the following ranges: 30-80dB, 40-90,
50-100dB, 60-110, 70-120, 80-130 and 30-130dB (auto). The display will reflect the range
for each button press.
Notes: Use Auto Range when the noise source is relatively steady. Use one of the Manual
ranges may be required if the dB levels are changing over a wide range.
Model 407764 Version 1.3 October 2001

\A)
ter
nd
;ay
Operation
1.
2.
3.
4.
Power the meter and select the desired Response Time (Fast or Slow) and Frequency
Weighting (A or C).
Select the desired range.
Hold the Instrument comfortably in hand or position on tripod. Point the microphone
toward the noise source, the sound pressure level will be displayed on the meter's LCD
display.
When MAX (maximum hold) mode is selected by pressing the MAX key, the instrument
captures and holds the maximum noise level reading on the display. Press the MAX key
again to clear the MAX reading.
Calibration
Note that a Sound Level Calibrator is required. Set up the meter as listed in Step 1 below.
To calibrate the meter;
1. Display: SPL (dBA)
Response Time: FAST
Disable the MAX function
Range: 70 to 120dB.
2. Insert the microphone carefully into the sound
level calibrator.
3. Power the calibrator and adjust the Sound Level Meter's
CAL potentiometer (as shown in figure at right) to match
the Calibrator's output.
4. Typically, a Sound Level Calibrator will supply 94dB
or 114dB at 1KHz. Adjust the Sound Level Meter's CAL
potentiometer for a 94dB or 114dB LCD display
(Figure-3)
'C
W'
de,
tor
ng
or
30.
ige
jal
Analog output
The 407764 has two analog output jacks located on its right side; one for AC and one for DC.
For DC, the meter transmits 10mv / dB. For AC the full scale value Is 0.707V. The output
impedance is 600a for AC and 100f2 for DC.
The supplied 3.5mm stereo mini-plug can be used to assemble a cable to connect to either of
the meter's analog output jacks. When using a stereo plug, like the one supplied, short the Tip
and the Ring (see diagram below). Ground (negative) connects to the Sleeve while the
positive signal is taken from the Tip/Ring. For mono plugs, ground connects to the Sleeve
while the positive signal is taken from the Tip. The meter output can then be transmitted to a
chart recorder, datalogger, or other data storage device.
(Figure 4) ,
Sleeve Tip
Sleeve Tip
ono
Stereo
Ring
K)1
Model 407764 Version 1.3 October 2001

DataLogging
The internal memory of the meter can store up to 16,000 reading in up to 255 recording
sessions (called sets). Prior to beginning data storage, the meter's real time clock and the
datalogger's sample rate must be set using the supplied software. The clock is set in the
Control Panel window and the sample rate is set in the Logger window.
1. Set the real time clock (if required).
2. Set the sample rate (if required).
3. To record data, press & hold the RECORD key for 3 seconds until the "RECORD"
symbol flashes once per second on the LCD. Press the Record key again to stop
recording data.
4. If the recording memory is full, the "FULL" symbol will appear on the LCD.
5. To clear the recording memory press and hold the RESET key and power the meter.
The LCD will show the "dEL" icon letting the user know that the datalog memory has
been cleared.
6. To Download or Record data via a PC refer to the PC Interface section below.
(figure 5)
PC Interface
Connecting the Meter to a PC
Refer to Figure 5. Connect the 9-pin male connector to the Sound Level Meter, and connect
the 9-pin female connector to the 9-pin C0M1 PC port. If C0M1 is used by the mouse,
connect the 25-pin female connector to the 25-pin COM2 PC port (you'll need to use the
included 9- to 25-pin adapter).
PC Requirements
486 IBM compatible PC or better
One 3.5" high density disk drive
Available serial port.
4M Bytes H.D. storage space
EGA or VGA monitor
Windows 95, 98,2000 NT Operating System
3-button or 2-button Microsoft compatible
mouse. At least a 486 PC is recommended
for displaying all software windows with a
fast sampling rate (such as 1 second). If a 386/25 PC is used, you can only open one
window (LIST, GRAPH, ANALOG) at a time when using fast sampling rates.
m
^3 1
(olololo^
1
Installing the Windows Application Program
Follow the instructions on the disk for installation.
Model 407764 Version 1.3 October 2001

Software Control Panel Description
The Control Panel (Figure 6)
g HANLL_Ver. 2.3
sovubleveluetek
ANALOG
106.4
<-RESET->
13:19:58 1 Sec
SAVEAS IQ^nii: PC SAHPLDC
EXIT
GTARTRECORDINC
:t
METER SIMULATION
The left side of the Control Panel window provides a replica of the meter's front panel and
display.
MAX: Hold and update maximum value
A/C A/C weighting selection
reset Reboot and dear the data memory
F/S Fast/Slow selection
REG Enable datalogging
LEVEL Set range
DATA ACQUISITION CONTROLS and DISPLAYS
MIN:
MAX:
TIME:
SAMPLING TIME
PC SAMPLING:
<-RESET->:
SYSTEM TIME SET:
SAVE AS:
OPEN FILE:
FILE NAME:
START RECORDING:
STOP RECORDING:
EXIT
Displays the minimum value recorded
Displays the maximum value recorded
Displays the Real Time CloGk=€etting
Display of data acquisition sampling rate (Fig 7)
Opens data acquisition sampling rate selection box. (Datalogging
sample rate is set in the MEMORY "Logger" window)
Resets thee MIN and MAX stored readings
Sets the meter's dock to the value of the pc clock
Opens the data file storage window (*.dat)
Opens the data file retrieve window (*.dat) (Fig.8)
Displays name and location of data acquisition file
After opening a file, click to start recording.
Stop recording and close the file
Close program
(Figure-7)
Selecting the datalog sample rate
Input Sanipiing Time
Enter the SAMPLING
TIME in seconds
|1 <- K- G5)
X]
OK
Cencel |
(Figure-8)
Opening a datalog file (*.dat)
Fie Dame:
Urtfie$oI|ype:
lOetaFlesr.dall
Eolders:
c:V..NeMtechW)undm'^
OK
J
Bc:\
B PROGRA-1
fe EXTECH
to SOUNDM-1
T]
Caned
Ne^Ifork...
J
r Bead only
"3 n
Diiyet:
3
01
Model 407764 Version 1.3 October 2001

DISPLAY SELECTIONS
(Figure-9)
GRAPH
PRWT unn GOT
dB
too -
SMwbw 1 Sw
Total Aoeoidr
^IME
(Figure-10)
LIST
SAVE OlAPH PRINT DOT
Date
iTi-
lvalue iTjpe |Ba( iRange
1 0/U
1
09-10-2001 14:01:59
66.3
A 50-100
2
09-10-2001 14:02:60 63.9 A
50-im
3
09-10-2001 14:02:01 64.7 A
50-100
4
09-10-2001 14:02:02 64.7 A 50-100
5
09-10-2001 14:02:03 64.7 A
50-100
6
09-10-2001
14:02:04
64.6 A
50-100
7
09-10-2001 14:02:05 85.2 A
50-100
OVER
B
09-10-2001 14:02:06 64.4 A
50-100
9 09-10-2001
14:02:07 85.6 A
50-100
10
09-10-2001
14:02:08
64.9
A
50-100
11
09-10-2001 14:02:09 63.8 A 50-100
12
09-10-2001
14:02:10 62.7
A
50-100
13
09-10-2001 14:02:11 63.5
A
50-100 OVER
14 09-10-2001
14:02:12 84.2 A
50-100
OVER
15 09-10-2001 14:02:13 66.2
A
50-100
OVER
1R
(Figure 11)
ANALOG
TIME OF METER
ID CODE
ID CODE
SAMPLING
14:18:37
SET
DATE TIME
Logger Window (memory setup/ data download)
The Logger window sets the sample rate of the meter's internal memory and provides the
cxjntrols to download display and save stored data.
MEMORY: Displays memory size
REMAINING Displays amount of
unused memory
When clicked,
downloads and displays
the meter's date and
time
Numeric Identification
code. Enter the code in
the box and click on the
bar to store the code.
Datalogger sample rate.
Enter the sample rate In
the box (in seconds) and
click on the SAMPLING
bar tastorb the value.
Click on the bar to download the stored data
TIME OF RECORDING Click on the bar to display sets downloaded. Click on a set to
select data for display
NUMBERS OF REC Displays the number of records (data points) in the selected set.
SHOW DATA Display, Save or Graph data from selected set
SAMPLING
NUMBERS OF REC
15
SHOW DATA
0HJ9-10—H;15:51
OmS-l 0—14:17:32
NUMBER OF SETS
8
Model 407764 Version 1.3 October 2001

DATA DOWNLOAD PROCEDURE
1. Click the MEMORY icon in the Control Panel screen.
2. Click the NUMBERS OF SETS button, the number of sets will appear.
3. Click on the TIME OF RECORDING button to view each recorded set.
4. Click on a SET in the TIME OF RECORDING box. The number of records in the set will
appear and the data will be downloaded from meter to PC. Save to disk if desired.
5. Click the SHOW DATA button for details on each record. Figure 13 shows the data list.
Select SAVE, PRINT, GRAPH, or EXIT from the menu choices.
Note: In the example for Figure 12, there are 3 sets of recorded data in memory. Set No. 3
has 15 records. Note: If you need to change the ID CODE or the SAMPLING time, click on
the desired parameter, type the changes and click on the bar.
(Figure-13) - List of datalogged set (Figure-14) - Graph of datalogged set
SAVE nUHT ORAPH EST
\amti
HEC
233
234
235
240
241
243
244
245
DATE
I TIME
99-04-09
99-04-09
99-04-09
99-04-09
99-04-03
99^)4-09
99-04-09
994M-09
99-04-09
99-04-09
99-04-09
99-04-09
99-04-09
08:15:55
08:15:56
08:15:57
08:15:58
06:15:59
08:16:00
08:16:01
08:16:02
08:16:03
08:16:04
08:16:05
08:16:06
08:16:07
l»9.2
69.3
68.2
6Z2
69.9
61.7
60.9
61.5
62.2
70.4
66.3
68.1
64.4
40-90
40-90
40-90
40-90
40-90
40-90
40-90
40-90
40-90
40-90
40-90
40 90
40-90
id
08:12:03
08:14:05 88:16:t
TIME
(Figure-15) - Selecting a range of datalogged records
KANCi:
PROM TO MEN MAX
24G
80
OK
•St.
.001
Model 407764 Version 1.3 October 2001

Calibration / Repair Services
Extech offers complete repair and calibration services for all of the products we sell. Fop
periodic calibration, NIST certification or repair of any Extech product, call customer service
for details on services available. Extech recommends that calibration be performed on an
annual basis to insure calibration integrity.
Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts
and workmanship for one year from date of shipment (a six month limited warranty applies on
sensors and cables). If it should become necessary to retum the instrument for service during or
beyond the warranty period, contact the Customer Service Department at [phone] ext.
210 for authorization or visit our website at www.extech.com (click on Contact Extech and go to
Service Department to request an RA number). A Return Authorization (RA) number must be
issued before any product is retumed to Extech. The sender is responsible for shipping charges,
freight, insurance and proper packaging to prevent damage in transit. This warranty does not
apply to defects resulting from action of the user such as misuse, improper wiring, operation
outside of specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fi tness for a specific purpose
and will not be liable for any direct, indirect, incidental or consequential damages. Extech's total
liability is limited to repair or replacement of the product. The warranty set forth above is inclusive
and no other warranty, whether written or oral, is expressed or implied.
s
Support Hotline [phone]
Tech support: Ext. 200; Email: [email protected]
Repair/Retums: Ext. 210; Email: [email protected]
Website: www.extech.com
Copyright © 2001 Extech Instruments Corporation. All rights reserved
including the right of reproduction in whole or in part in any form.
10
Model 407764 Version 1.3 October 2001

Appendix - Typical 'A' Weighted Sound Levels
* For
ice
an
arts
on
3 or
ext.
3 to
be
les,
not
tion
ech
ose
otal
>ive
50 HP Siren (100')
Jet take-off (200')
Riveting machine
Subway (20')
Pneumatic drill (SO')
Vacuum cleaner (10')
Large store
Small office
Residential area (night)
Whisper (5')
Threshold of hearing
130-
110
90
70
50
30
10-
140
120
100 Chain saw
80
60
40
Boiler room
Freight train (100')
Speech (1')
Large Office
Residence
20 Sound studio
001
11
Model 407764 Version 1.3 October 2001

Software Protocol
Data Protocol Baud rate: 9600bps
Bytei
Byte2
Byte3 Byte4
Bytes
02
Status
Function
03
Leading byte
Ending byte
Bit7
Bite
Bits
Bit4
Bits
Bit2
Bit1 BitO
0
Fast C
Normal
Normal
Normal
0
00
30-80
1
Slow
A
Max Full
Rec
0
0
1
40-90
0
1 0
50-100
0
11
60-110
1 00
70-120
1 0
1
80-130
1
1
0
30-130
111
Function Byte3
Bit7
Bite
Bits
Bit4 (xlO^)
Bit3-0 (xlO)
0
Normal
Normal
Normal
00-19
1
OVER
UNDER
BT
Bit7-4(x10") Bit3-0(x10")
0
00-99
1
Command Protocol
1 ^
YY
MM
dd
hh
mm
ss
1 leading byte
year
month
date
hour
mm
sec
W
hiah bvte low byte
leading byte
1 — essss sec
X
high byte low byte
leading byte
1 - essss
ID Code
Version
ID code
Data sets
Last address
Sample rate
2bytes
1 byte
1 byte
1 byte
3 bytes
2 bytes
Get time and date - Output "C" - Receive 6 bytes (YY+MM+dd+hh+mm+ss)
Receive 6 bytes (Sets+YY+MM+dd+hh+mm+ss+Status+Sample
rate+Records)
Get Record - Output "K"+N records"
Receive (YY+MM+dd-thh+mm+ss+Status+Sampling rate+Records+1
record+Z™* record+...+nth record)
Erase Command: "EEE" (3 bytes)
Switch Fast/Slow: "F" (1 byte) ^
Switch A/C: "A" (1 byte)
Switch range: "U" (up), "P" (down) (1 byte)
Set MAX spi; "M" (1 byte)
Stop Recording: 'T' (1 byte)
Start Recording: "S" (1 byte)
12
Model 407764 Version 1.3 October 2001