407355 Datasheet, PDF (5/17 Pages) Extech Instruments Corporation. – Noise Dosimeter with PC Interface

Operation
Getting Started
1. Power the instrument by pressing the green button.
2. When the unit is turned on, all display annunciators switch on briefly followed by
‘dOSE’, the Criterion Level (Lc), Threshold Level (Lt), and Exchange Rate (ER)
respectively. These parameters are defined in the Noise Exposure related sections of
this manual.
3. If the meter does not switch on when the power button is pressed, check that the
batteries are installed and are fresh. Refer to the Battery Replacement section of this
manual.
4. To turn the meter OFF, press and hold the green power button; the display will count
down from 3dB to 0dB and then switch off.
5. The 407355 can be used as a Sound Level Meter or a Dosimeter.
Sound Level Meter Operation (dBA)
Press the MODE button repeatedly until the unit of measure is dBA (A-weighted decibels).
In SLM mode the meter operates as a Type 2 sound level meter. The 407355 measures
and displays sound pressure levels from 70 to 140dB. Read the measured sound level on
the LCD. For Sound Level measurements < 68dBA the LCD will display dashed lines. For
readings > 115dBA, the headphone icon appears. For readings > 140dBA, the Peak
Detector PK icon appears.
Datalogging
In Sound Level Meter (dBA) mode, the internal memory of the meter can store up to 8800
readings. Press the RUN key to start recording the measured readings. The MEM icon will
appear in the display. To stop datalogging, press the RUN key again. The MEM icon will
no longer be displayed on the screen. To download the data to a PC, refer to the PC
Interface section in this manual.
Note: If the low battery mark is flashing or Dosimeter surveys E1 through E5 have been
saved in memory, the datalogging function will not operate. The memory must be cleared.
To clear memory, turn the meter off then hold down the RUN key and turn the meter on. E-
EP will appear in the display to indicate that all memory data has been cleared.
Dosimeter Operation (Accumulated Noise Exposure - %DOSE)
1. Program the Response Time (Fast or Slow), Criterion Level (Lc), Exchange Rate (ER),
and Threshold Level (Lt) manually (see Programming section) or through the supplied
software (see PC Interface section).
2. Use the MODE button to select %DOSE as the unit of measure.
3. Select an unused Event Bank (E1 through E5) using the EVENT button.
4. Attach the meter to the user’s belt buckle, breast pocket, or where convenient
5. Clip the microphone as close as possible to the user’s ear (shirt collar, for example)
using the lapel clip.
6. Route the cable as to not hinder the working movements of the user.
7. Press the RUN button to begin measuring accumulated noise exposure. The Clock
display icon will switch on.
8. Press the RUN button momentarily to PAUSE the test (PAUSE display icon will switch
on). Press the RUN button again to resume the test (PAUSE icon will switch off).
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407355 Version 2.4 9/07