Extech Instruments 407790A-NIST User manual

User Manual

Real Time Octave Band Analyzer

Model 407790A

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Table of Contents

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1. Introduction

Congratulations on your purchase of the Extech 407790A Real Time Octave Band
Analyzer. This auto ranging Type 2 integrating sound level meter features 1/1 and 1/3
Octave Band real-time noise analyses. The 407790A offers five measurement
parameters: SPL (Sound Pressure Level), Leq (Equivalent Continuous Sound Pressure
Level), SEL (Sound Exposure Level), Lmax (Maximum Sound Pressure Level), and Lmin
(Minimum Sound Pressure Level). The built-in memory stores 12,280 data records in
sound level mode and 1024 records in Octave mode. The stored data can be easily
transferred to a PC with the 407790A software and USB cable. This meter permits
choice of , or Flat and Slow / Fast /impulse response times. AC and
DC analog output signals are available for chart recorders and other external recording
devices. Careful use of this device will provide years of reliable service.

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1.1 Instrument Care

Do not attempt to remove the mesh cover from the microphone as this will cause damage
and affect the accuracy of the instrument.

Protect the instrument from impact. Do not drop it or subject it to rough handling.
Transport it in the supplied carrying case.

Protect the instrument from water, dust, extreme temperatures, high humidity and direct
sunlight during storage and use.

Protect the instrument from air with high salt or sulfur content, gases and stored chemicals,
as this may damage the delicate microphone and sensitive electronics.

Always switch the instrument off after use. Remove the batteries from the instrument if it
is not to be used for a long period of time. Do not leave exhausted batteries in the
instrument, as they may leak and cause damage.

Clean the instrument only by wiping it with a soft, dry cloth or, when necessary, with a cloth
lightly moistened with water. Do not use solvents, abrasives, alcohol or cleaning agents

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1.2 Features

The Sound Level Meter complies with the requirements of IEC 61672-1:2003 standard for a
Class 2 instrument. See specifications section for more applicable standards that apply to this
meter.

1/1 octave band analysis from 31.5Hz to 8kHz
1/3 octave band analysis from 25Hz to 10kHZ
Can perform 1/1 and 1/3 octave band analysis simultaneously
4GB Micro SD card
USB interface
Datalogging function
AC/DC signal output available for level and graphic recorder
Comparator output function
External trigger input function
Real time clock with calendar
Main channel (sound meter, analyzer mode)
Sub Channel (sound level meter mode)

The 407790A allows the following quantity measurements.
Simultaneous measurements of all items with selected time weighting and frequency

characteristics.

Sound level Lp
Equivalent continuous sound Leg
Sound exposure level SEL
Maximum sound level Lmax
Minimum sound level Lmin
Percentile sound level LN (L05, L50, L90, L95) calculated from Lp
Frequency rating A, C, Z
Time weighting

Main Channel Fast, Slow, 10ms, impulse
Sub Channel Fast, Slow, 10ms, impulse

Safety Symbol: Complies with EMC

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2. Descriptions

2.1 Meter Description

Refer to the diagram below for the following descriptions.

1. Windscreen

2. Microphone

3. Display

4. Operation keys

5. 6VDC adapter jack

6. DC analog output jack

7. AC analog output jack

8. Comparator output jack

9. Trig IN jack

10. Micro SD card slot

11. Power switch

12. Hand strap

13. USB port

14. Battery compartment

15. Tripod mounting screw

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2.2 Operation Buttons

START/STOP button
Press to start or stop for recording the sound pressure measurement.

PAUSE/CONT button
Press to temporarily pause ( ) a measurement) or resume ( ) measurement.

M button

Press to scroll through and select different processing modes.

LEVEL

Press to select the level range for measurement. The following five settings are available.
20 to 90 dB, 20 to 100 dB, 20 to 110 dB, 30 to 120 dB, 40 to 130 dB.

GRP/ NUM button

Press to switch between graph and numeric display for Octave measurements.

SLM 1/1 1/3 button

Press to switch to select the sound level meter display and analysis screen.
(SLM, 1/1, 1/3, 1/1&1/3)

MENU

Press to enter menu screen to setup various menu parameters. Press again to close the
menu.

R button

Start or stop the auto Record process or press to manually store the measurement data

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into memory.

/

Press to move the octave frequency band marker during frequency analysis.

-

+

FREQ WEIGHT TIME button

ponse (Z).

The TIME WEIGHT selects the time weighting function for the main channel. (F, S, 10ms, I)
Fast: 125ms; Slow: 1000ms; 10ms; Impulse: 35ms

Note: The frequency and time weighting for the sub channel can be selected by accessing
the menu screen.

button (Backlight/Enter)
Backlight powers on the display backlight. Press the button again to turn backlight off.
When automatic Backlight Off function is selected from the menu screen, the backlight will
turn itself off automatically after the preset time.

Enter button will finalize a setting of an item in a menu or any other setting.

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2.3 Display Screen

Measur

ement in pr

ogr

ess s

ymbol

Overload indication

y

equency weighting

Under

Memory

Bargraph

range indication

Main channel

Frequency weighting

Time weighting

Main channel level

display

Power
status

Mode of analysis

Manual store full indication

USB link status

Trigger mode

Elapsed time

Comparator ON

Auto store full indication

Store mode

Address

Level range

Sub channel level displa

Sub channel

me weighting

Ti

Fr

Current time

Current date

1.

2. Measurement in progress: When a measurement recording is in progress or during auto store

the symbol flashes. During measurement pause the

3. USB Link Status: Shows if the USB is enabled or disabled.

4. Trigger Mode: Controls the measurement and memory auto store start behavior. Available

modes are: Level 1 (LV1), Level 2 (LV2), EXT (EXT), and time (TIME).

5. Elapsed Time: Displays the elapsed time in seconds during processing and storing memory.

6.

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7.

8.

9. Bar graph: Displays the sound level as a bar graph. (The display is updated every 100ms)

10.
LEVEL button.

11. Under-range indication: When a signal is under-range the UN symbol will appear on the

screen. Use the LEVEL button to decrease the level range setting. If processed data is

12. Overload indication: When a signal overload is detected, the screen will display OV for at

least 1 second. Use the LEVEL button to increase the level range setting. If processed

13.

14.

(10ms), I: Impulse (35ms)

15. Main channel level display: Displays the measured sound level in the main channel.

(The display is updated every second).

16. Sub channel frequency weighting: Indicates the sub channel frequency weighting

characteristic. A: A-weighting, C: C-weighting, Z: Z-weighting (Flat response).
The sub channel frequency weighting can be set from the menu screen.

17. Sub channel time weighting:

(10ms), I: Impulse (35ms)

18. Sub channel level display: Shows the measured sound level in the sub channel.

(The display is updated every second)

19. Power status: When operating the meter on battery power the yellow segments will

decrease as the battery power drains. When the segment starts to flash, replace batteries.

20. Manual store full: When the manual stored memory is full, the MFul symbol is displayed.

The manual data store capacity is 250 sets.

21. Auto store full: When the auto store memory is full, the AFul symbol is displayed. The auto

store capacity is 250 blocks.

22. Comparator ON: When the comparator function has been set to ON and a signal exceeds

the comparator output jack, the indicator Cmp will appear on the display. A signal will
output from the comparator output jack on the side panel (open collector).

23. Current date: Displays the current date

24. Current time: Displays the current time

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2.5 Numeric Display screen

Example for 1/1 OCT, 1/3 OCT, and 1/1 & 1/3 OCT analysis screen are shown below.
Use the and buttons to view a frequency that is not displayed.

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3. Measurement Preparation and Setup

1. Battery installation: Remove the rear battery cover as shown below and insert (4)

size alkaline batteries. Take care to observe battery polarity. Replace the battery cover.

2. Battery replacement: When the battery voltage drops below operating voltage,

battery symbol flashes on the display.

3. AC adaptor connection: Insert the adaptor in the DC 6V jack on the side panel. When the AC

adapter is connected, the meter will be powered from the adapter even if batteries are

installed.
Notes:
To prevent the risk of damage, use only the factory supplied AC adapter.
To prevent the risk of battery leakage, remove the batteries from the meter when the meter is

not in use.

3.1 Setting the Date and Time

Date and time information is stored with each record saved. Set the date and time as follows:

1. Press power switch ON and wait until the measurement screen appears.

2. Press the button. The menu list screen will display.

3. Press the + / - button to D) Date setting (Y/M/D) and then press the enter

button.

4. Press the +/ - button to set the value. Press button to confirm.

5. Continue pressing the above buttons to scroll through and set each option for date and time.

The meter will continue to scroll through setup for date Y/M/D and then the time settings

h/m/s.

6. When the settings are correct, press the button to exit the setting mode. The clock will

start running with the new settings.

7. Press MENU button to return to the measurement screen.
Note: The clock has an error of about 1 minute per month. Before taking measurement, be sure

to check and set the time if required.

Date

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Time

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3.2 SD Memory Card

Measurement data can be stored on a removable SD memory card for later use.
Note: Power OFF the meter before inserting or removing the memory card.

Use only a 4GB micro SD card. Removing SD card or powering the meter off while data is storing
to the card can cause internal data to be destroyed.

1. Insert the card taking care to observe the correct orientation. Push the card in carefully,

until it is properly sealed.

2. To remove, push the card. The SD card with pop out and can be removed.

3.3 Setting the Backlight Auto Off time

1. Press the to turn the backlight on or off.

2. Press the key to bring up the menu list screen.

3. Use the + / - key Backlight Auto Off then press the key.

4. Use the + / - key to select the automatic turn off time then press the key. Options

are: 30 seconds, 1 minute, 3 minutes or OFF (without automatic turn - off function).

5. Press key to return to the measurement screen.

To turn the backlight off before the automatic turn - off time, press the key.

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3.4 Sub Channel Settings

To access the sub menu setting press the following buttons.

1. Press the MENU button to enter the menu list screen.

2. Use the + / - buttons G). Sub Time Weight then press button.

3. Use the + / - button to select the desired time weighting

F, S, (10ms) or I (Impulse 35ms), then press button.

4. Press the + / - buttons H). Sub Freq Weight then press button.

5. Press the + / - buttons to select the desired frequency weighting A, C or Z, then press

button.

6. Press button to return to the measurement screen.
Note: There is no frequency analysis function for the sub channel. Only the all - pass value is

measured.

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3.5 Selecting the Lmax/Lmin type

Band - (Band maximum/band minimum):

The analysis result applies to the point where the level for each frequency band was maximum

or minimum within the sampling period.

AP - (All-pass maximum/all-pass minimum):

The analysis result applies to the sub channel all-pass and band-pass level values taken at the

point where the all-pass level in the main channel was maximum/minimum within the

sampling period.

AP (S) - (All-pass maximum/all-pass minimum):

The analysis result applies to the band-pass level values (excluding the sub channel all-pass

levels) taken at the point where the all-pass level in the main channel was

maximum/minimum within the sampling period. The sub channel all-pass level is taken at

the maximum/minimum point within the sampling period, independently of the main

channel level.

1. Press the button to enter the menu list screen.

2. Use the + / - buttons I). Lmax/Lmin Type then press button.

3. Use the + / - buttons to select the desired Band, AP or AP (S) type then press button.

4. Press button to return to the measurement screen.

This setting is effective in SLM mode and Octave band analyzer mode.

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3.6 Comparator Output Operation

The comparator output is an open collector output that can be used to control external

equipment.

1. Press the button to enter the menu list screen.

2. Use the + / - buttons J). Comparator then press button to display the

ON/OFF setting.

3. Press the + / - buttons ON then press button.

4. Press the

then press button. (Setting range 25 to 130dB, 1 - dB steps)

5. Follow the above steps to select 2). Comparator Band et the band to desired level then

press button

6. Press the button to return to the measurement screen.

+

- buttons again to select 1). Comparator Level et the desired level

AP

AP

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AP

AP

AP

AP

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Comparator signal output continues for 0.5 seconds after the signal crosses the threshold level

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3.7 Trigger Mode Setup and Operation

A measurement can be initiated by one of three triggers: time trigger (time-controlled
triggering), level trigger (sound level controlled triggering), and external trigger (triggering by an
external signal).

Level trigger 1: Measurement starts when the trigger level is exceeded and ends after the
measurement time.

The trigger level is valid at any time.
Setting items:
Trigger Slope Type: +, ­Trigger Level: 25 to 130dB, 1-dB steps.
Trigger Band: MAIN AP

Level trigger 2: Single measurement is made when trigger level is exceeded.
The trigger level is valid at any time.
Setting items:
Trigger Level: 25 to 130dB, 1-dB steps.
Trigger Band: MAIN AP 8kHz (1/3 octave bands).

Time trigger: This is a reoccurring trigger timer that starts a measurement after a trigger timer.
The measurement ends after the measurement time.
The trigger timer is valid at all times.
Setting items:
Trigger Time: h:m:s

External trigger: A Measurement starts at falling edge of a logic-level (0 to 5V logic) signal at the
external trigger input. A Pulse width of 1ms or more is required.

The external trigger is valid at all times.

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Trigger Operation - example

1. Sound Level

2. Time

3. Slope + Trigger

4. Slope - Trigger

5. Trigger Level

3.7.1 Trigger Setup

1. Chose trigger operation [off, Level 1, Level 2, External, or Time].

2. Set the Trigger Band: AP or Octave band frequency

3. For Level 1 and 2: chose the Trigger level in dB.

4. External Trigger, chose slope (+ or -)

AP

3.7.2 External Trigger Setting

1. Press the MENU button to enter the menu list screen.

-

2. Use the

3. Use the

4. Press the button to return to the measurement screen.

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+

-

+

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K). Trigger button.

EXT button.

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3.7.3 Trigger Time Setting

This is a reoccurring Trigger that will start a meter recording at a specific Trigger delay time
setting and the recording will stop at the set Measurement time and then start up again at the
trigger wait time.

1. Press the button to enter the menu list screen.

-

2. Use the

3. Use the

4. Use the

5. Use the

6. Use the

7. Use the

8. Press the button to return to the measurement screen.

+

+

+

+

+

+

Hour:Minute:Second then press the button.

buttons to select K). Trigger then press the button.

-

buttons TIME then press the button.

-

-

and buttons to set the value to AP then press the button.

-

buttons 3). Trigger Time then press the button.

-

and buttons to set the value of the reoccurring trigger timer

2). Trigger Band button.

AP

AP

3.7.4 Trigger Level Setting

The Triger can be set to start a meter recording at a specific Trigger dB level setting.

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1. Press the button to enter the menu list screen.

-

2. Use the

3. Use the

4. Use the

5. Use the

6. Use the

7. Use the

8. Use the

9. Use the

Note: For LEVEL 2 trigger, ignore the slope setting and only use the Slope+ trigger.

10. Press the button to return to the measurement screen.

11. Press the R button on the meter to start automatic recording. The meter will start

+

+

button.

+

+

button.

+

+

+

+

button.

recording when the trigger level is exceeded.

buttons K). Trigger then press the button.

-

button to select the desired option LEVEL1 LEVEL2 then press the

-

buttons 1). Trigger LEVEL then press the key.

-

buttons to set the desired trigger level value (25 to 130). Then press the

-

buttons 2). Trigger Band then press the button.

-

buttons to select the desired trigger band then press the button.

-

buttons 4). Slope Type then press the button.

-

buttons to select the desired trigger slope + or Slope-. Then press the

AP

AP

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4. Measurements

All processing functions provided by the meter (Leq, SEL, Lmax, Lmin, Ln) are carried out
simultaneously. For example, when equivalent continuous sound level measurement is selected,
the sound exposure level and percentile level are also determined.

4.1 Sound Level Measurements

1. Press the power button to power on the meter. After the power-on screen displays the SLM

measurement screen will appear.
The measurement parameter settings that were active before the meter was turned off will be

saved.

2. Use the FREQ WEIGHT TIME button to select the Main Channel frequency weighting

3. Use the FREQ WEIGHT TIME button to select the Main Channel time weighting characteristic.

For normal sound level

4. Use the LEVEL buttons to set the dB level range. Choose a setting in the middle of the

display range of the main channel bar graph indicator.

OV UN setting.

5. The Main channel and Sub channel level indicators display the currently measured sound

pressure levels. The reading is updated once every second.

6. The button can be used to stop and resume the updating of the level indication.

In sound level meter mode, the bar graph indication will stop during pause.

In the pause condition, a pause symbol ( ) appears on the display.

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4.2 SEL, Leq, Lmax, Lmin, LN Measurements

3. Use the FREQ WEIGHT TIME button to select the time weighting characteristic. For normal

sound level measurements

4. Use the LEVEL buttons to set the level range. The main channel bar graph indicator should be

in the middle of the range.

OV UN

-

+

-

+

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symbol

Important: During measurement, the LEVEL button, FREQ WEIGHT TIME button, TIME

WEIGHT and SLM/RTA function are disabled. Be sure to complete all settings before

starting the measurement.

symbol

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4.3 Sound Level and Octave Band Analysis Measurement

1. With the power ON wait until the SLM measurement screen appears on the display.

2. Use the button to select the desired 1/1 OCT, 1/3 OCT or 1/1 & 1/3 OCT band or

SLM measurement screen.

3. Use the FREQ WEIGHT TIME button to select the frequency weighting characteristic. For normal

4. Use the FREQ WEIGHT TIME button to select the time weighting characteristic. For normal sound

5. Use the LEVEL buttons to set the level range.
Select a setting in which the main channel all-pass value indicator is in the middle of the range.

OV UN

6. The level indicator displays the currently measured Sound band level.
Use the button to toggle the measurement screen between graph and numeric display.
If the graph display is selected, use the and buttons to move the cursor to the desired

frequency band.
In the 1/1 & 1/3 OCT numeric display, frequencies that are currently not displayed can be called up

with the and buttons.
To stop or resume updating the band level indication press the button. When

pause is selected, a pause symbol ( ) appears on the display.
Important: During sound band measurement, do not press the key or other parameter

symbols will be displayed.
The sound band level is being displayed when there is no character string after the basic

indicator.
LAF: Sound band level is being displayed.
LAeq: Sound band level is not being displayed.

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4.4 Sound Band - Leq, SEL, Lmax, Lmin and LN Analysis Measurement

1. Power on the meter and wait until the SLM measurement screen appears.

2. Use the button to select the desired 1/1 OCT, 1/3 OCT or 1/1 & 1/3 OCT band or

SLM measurement screen.

3. Use the FREQ WEIGHT TIME button to select the frequency weighting characteristic. For

4. Use the FREQ WEIGHT TIME button to select the time weighting characteristic. For normal

measurements

5. Use the LEVEL buttons to set the level range. Select a setting in which the main channel

all-pass value indicator is in the middle of the range.

OV UN

-

+

-

+

symbol flashes

Important

During measurement, the LEVEL button, FREQ WEIGHT TIME button, TIME WEIGHT

and SLM/RTA functions are disabled. Be sure to complete all settings before starting the

measurement.

12. When the measurement is completed, the symbol disappears.
If OV displayed, the processed data includes data where the sound level signal caused an

overload condition.

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UN sound level signal

caused an under-range condition.

(SEL)

E

13. Press the button to cycle through the Lp Leq L

Lmin L05 L10 L50 L90 L95 measured value on the screen.
Pressing the button switches the measurement screen between graph and numeric

display.
In graph display, use the and buttons to move the cursor to the desired frequency band.
In the 1/1 & 1/3 OCT numeric display, frequencies that are not displayed can be called up with

the and buttons.
The button can be used to stop and resume the updating of band level indication. In

the pause condition, a pause symbol ( ) appears on the display. (The pause interval is not

included in the measurement time.)
During measurement, you can use the key to check the measured values as currently

calculated.

Lmax

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5. Storing Data to Memory

The meter can store measurement data in the internal memory or on a micro SD card. There are three

different ways of storing data, as listed below.

Manual:

In this mode, the operator stores the measured sound level data and processed value data into the

memory manually.

Press the record button to cause the current sound level and processed values derived from

the measurement, as well as the measurement parameters and time of recording to be recorded

in a single measurement.
Memory capacity: max. 250 data sets
Manually stored data can be recalled by the meter.

Auto 1:

Sound level meter mode

Continuous store of main channel and sub channel all-pass values as 1 set, at preset record

interval times.

Octave Analyzer mode

Continuous store of main channel sound level Lp values for each band and all-pass values, sub

channel all-pass values as 1 set at preset record interval time.

Auto 2:

Sound level meter mode

Continuous store of main channel and sub channel all-pass values as 1 set at preset

measurement integrate time.

Octave Analyzer mode

Continuous store of main channel sound level Lp values for each band and all-pass values, sub

channel all-pass values as 1 set at preset measurement integrate time.
Automatically recorded data can be retrieved using the supplied software.

5.1 Manual Memory Storage

-

+

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-

+

-

+

-

+

Note: When address 250 is reached, the MFul symbol will be displayed and no more data can be

stored.

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5.2 Recalling Manually Stored Data

-

+

-

+

-

+

/

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5.3 Erasing Manually Stored Data

-

+

-

+

AP

AP

AP

AP

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5.4 Auto 1 Memory Storage

-

+

-

+

-

+

-

+

-

+

-

+

-

+

-

+

LEVEL

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5.5 Auto 2 Memory Storage

-

+

-

+

-

+

-

+

-

+

-

8. Press the

1 second to 23h59m59s, then press the key.

11. Set the other measurement parameters (trigger mode, sub channel etc.) as required, using

the button to select settings.

12. Press the button to return to the measurement screen.

13. Press the button to start the measurement. If a trigger has been set, measurement will

start when the trigger conditions are met.

+

+

+

and the buttons to set the desired measurement integrated time from

-

-

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5.6 Erasing Auto Stored Data

-

+

-

+

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6. Software Download and Installation

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7. Sound Pressure Level - Technical notes

1. The decibel (dB)
The range over which the human ear responds to sound pressure (noise) is extremely large; in

Pascals (Pa) it is 20 Pa (the threshold of hearing) to 100 Pa (the threshold of pain). The

measurement of sound pressure has been made more convenient by the use of the decibel,

which is logarithmic. However, decibels are non-linear and therefore cannot be added

together. A simple rule is that doubling the amplitude of the noise under test causes the

level to rise by 3dB.

2. SLM-sound level meter: Instantaneous sound pressure level (SPL) is used for spot checks to

establish instantaneous noise levels. SPL is defined by the logarithmic equation:

SPL (in dB): 20 log

Where P = rms measured sound pressure level
P0 = rms reference sound pressure level (20 Pa)

3. Leq-level equivalent (continuous): Leq is used to assess the rms average noise level over a

preset period of time, often the starting point of a noise assessment. To take a Leq

measurement the period of time over which it is to be made must be selected. The longer

the period of measurement time, the more accurate the Leq reading will be, a typical

period is 8 hours (the length of a working day).

4. SEL Sound exposure level (LE)

P

10

0

P

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8. Calibration

Calibrating the 407790A requires an acoustical calibrator such as the Extech Model 407766 or

407744 that can provide 94.0dB or 114dB at 1kHz.

1. Set the power switch to the OFF position.

2. Press and hold the

3. Insert the microphone into the opening of the acoustical calibrator.

4. Switch the calibrator ON (1kHZ 94dB or 114dB)

5. Use the

6. Press the button to store the calibrated value.

7. Switch the calibrator and sound meter OFF.

8. Remove the calibrator from the microphone very slowly to avoid damaging the

microphone.

+

+

-

-

(adjust range from -12.8 to 12.7dB).

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9. Specifications

level meter

Applicable Standards: ±1dB high accuracy meets Class 2 standards (IEC 61672-2013 and

ANSI/ASA S1.4/Part 1), IEC 61260-1: 2014 Class 2, ANSI S1.11: 2004 Class 2, ANSI S1.43:

1997 Type 2
Measurement functions: Simultaneous measurement of main channel and sub channel.

Frequency weighting and time weighting are set independently for main and sub channel.

Sound level meter mode: All-pass processing for the measurement items listed below is

carried out separately for the main channel and sub channel

Analyzer mode: For the main channel, octave, octave 1/3 or simultaneous octave, 1/3

octave band real-time processing and all-pass processing are carried out.

For the sub channel, only all-pass processing is carried out.

Processing types in each operation mode

Channel Main Sub

AP/OCT AP AP

Sound

mode

Analyzer
mode

Frequency

weighting

Time weighting F/S/10ms/I F/S/10ms/I

Measurement

values

AP/OCT AP, OCT AP

Frequency

weighting
Time weighting F/S/10ms/I F/S/10ms/I
Measurement

values

Lp, Leq, SEL, Lmax, Lmin, L

Lp, Leq, SEL, Lmax, Lmin, L

A/C/Z A/C/Z

N

Lp, Leq, SEL, Lmax, Lmin, L

A/C/Z A/C/Z

N

Lp, Leq, SEL, Lmax, Lmin, L

N

N

Measurement time: 1 to 59 seconds, 1 to 59 minutes, 1 to 24 hours
Microphone: ½ inch electret condenser type (Free field)
Display: Backlit color TFT LCD (320×240 dot matrix)
Update frequency: 100ms
Accuracy:

Measurement Frequency range:

Frequency weighting:
Inherent noise: A-weighting max. 17dB; C-weighting max. 25dB; z-weighting max. 30dB

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±1.0dB (ref 94dB @1kHz)

Octave analysis 31.5 Hz

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8 kHz; 1/3 Octave analysis 25 Hz to 10kHz

to

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Time weighting:

Storage type

Main channel: Fast (125ms), Slow (1000ms), 10ms, Impulse (35ms)
Sub channel: Fast (125ms), Slow (1000ms), 10ms, Impulse (35ms)

Measurement level range:

A-weighting: 25 to 130dB
C-weighting: 33 to 130dB
Z-weighting: 38 to 130dB

Total meter range: 25dB to 130dB (A-weighting, 1kHz)
Linear operating range: 90dB
Level Range: 20 to 90dB, 20 to 100dB, 20 to 110dB, 30 to 120dB, 40 to 130dB
Sampling cycle: 20.8 µS (LN: 100ms)
Trigger function: Controls measurement and memory store start

Level 1: Trigger level (1-dB steps) serves as threshold for starting measurement
Level 2: Single measurement is carried out when trigger level is exceeded
EXT: External trigger connector for logic-level signal with falling edge detection
TIME: Trigger event recurrence interval (trigger time) is set.

Store: Sound level values and processing results are stored in manual store or auto store mode.

Data can be stored in internal memory or on micro SD card.

Manual store: Data for measurement results and measurement start time are stored manually,

in single address increments.

Data store capacity: max. 250 data sets.
Auto store: Measurement results are stored continuously at the preset record interval time (for

Auto 1) or the preset measurement integrated time (for Auto 2), and the measurement
time.

Data store capacity: Memory capacity can be divided to 250 blocks max.
Memory capacity: See Table below (Manual/Auto storage blocks are separate)

Mode

Sound level meter 25087 data sets 29992366 data sets

1/1-octave analysis 16185 data sets 19944162 data sets

1/3-octave analysis 9466 data sets 11942248 data sets

1/1 and 1/3 OCT mode 7839 data sets 9946834 data sets

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Flash SD card

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Data recall: Allows viewing of the manually stored data.
AC output: 1 Vrms
DC output:
External trigger input: Detection of 0 to 5V logic- level signal, falling edge trigger, pulse width

1ms or more

USB: Allows connection to a computer as storage device, or use a communication device for unit

control via communication commands.

Power: Four (4) C size 1.5V alkaline batteries
Battery Life: Approx. 2 hours
External DC power supply: 6 VDC, 1A
Operating Temperature/Humidity: -10 to 50oC (14 to 122oF); 10 to 90%RH
Storage Temperature/Humidity: -10 to 60 oC (14 to 140oF); 10 to 75%RH
Environment conditions: Altitude up to 2000 meters
Dimensions & Weight: 34.5 × 10 × 6cm (13.6 (H) x 4.0 (W) x 2.4 ); Approx. 950g (33.5 oz.)

including batteries

Accessories: Four (4) C 1.5V batteries, hard-shell carrying case, CD-ROM, USB cable, 4GB micro SD

card, Windscreen, 3.5mm plug, and AC adaptor

Optional accessories: Microphone extension cable (4.7m (15ft), p/n 407764-EXT), Sound level

calibrator, Tripod

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10. Two-Year Warranty

FLIR Systems, Inc. warrants this Extech brand instrument to be free of defects in

parts and workmanship for two years from date of shipment (a six-month limited
warranty applies to sensors and cables). To view the full warranty text please visit:

Calibration and Repair Services

FLIR Systems, Inc. offers calibration and repair services for the Extech brand

products we sell. We offer NIST traceable calibration for most of our products.
Contact us for information on calibration and repair availability, refer to the contact
information below. Annual calibrations should be performed to verify meter
performance and accuracy. Product specifications are subject to change without
notice. Please visit our website for the most up-to-date product information:

.

Contact Customer Support

Customer Support Telephone
Calibration, Repair, and Returns email
Technical Support

Copyright © 2020 FLIR Systems, Inc.

All rights reserved including the right of reproduction in whole or in part in any form

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Garantía de dos años

FLIR Systems, Inc., garantiza este Instrumento marca Extech a estar libre de

defectos en partes o mano de obra durante dos años a partir de la fecha de
embarque (se aplica una garantía limitada a seis meses para cables y sensores).

Servicios de reparación y calibración

FLIR Systems, Inc., ofrece servicios de reparación y calibración para los

productos marca Extech que vendemos. Ofrecemos calibración rastreable de
NIST para la mayoría de nuestros productos. Póngase en contacto con nosotros
para obtener información sobre la disponibilidad de calibración y reparación,
consulte la información de contacto a continuación. Se deben realizar
calibraciones anuales para verificar el funcionamiento y la precisión del medidor.
Las especificaciones del producto están sujetas a cambios sin aviso. Por favor,
visite nuestro sitio Web para obtener la información de producto más actualizada:

.

Póngase en contacto con el servicio de atención al cliente

Teléfono de atención al cliente -

Correo electrónico de Calibración, Reparación, y Devoluciones:

Soporte Técnico:

Copyright © 2020 FLIR Systems, Inc.

Reservados todos los derechos, incluyendo el derecho de reproducción total o parcial

en cualquier medio

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Garantie de deux ans

FLIR Systems, Inc. garantit que cet instrument de la marque Extech est exempt

de défauts de pièces et de fabrication; deux ans à
compter de la date d'expédition (une garantie limitée de six mois s'applique aux
capteurs et aux câbles). Pour voir le texte complet de la garantie, veuillez visiter

Services

FLIR Systems, Inc. offre des services d'étalonnage et de réparation pour les

produits de la marque Extech que nous vendons. Nous offrons un étalonnage
traçable NIST pour la plupart de nos produits. Pour plus d'informations sur la
disponibilité des services d'étalonnage et de réparation, contactez-nous (reportez­vous aux informations de contact ci-dessous). Des étalonnages annuels doivent
être réalisés afin de vérifier les performances et la précision du compteur. Les
spécifications produit sont sujettes à modification sans préavis. Veuillez consulter
notre site Web pour obtenir les informations les plus récentes sur nos produits:

Téléphone

E- :
Support technique:

Copyright © 2020 FLIR Systems, Inc.

Tous droits réservés, y compris la reproduction partielle ou totale sous quelque forme

que ce soit

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