Calibration Procedure; Erase The Memory - Extech Instruments 407355-NIST User Manual

Calibration Procedure

Note that an acoustical calibrator (such as the Extech 407744 or 407766) is required to calibrate the
407355. Extech Instruments can also calibrate the instrument and provide an N.I.S.T. certificate if
desired.
1. Set the instrument to the Sound Level Measurement Mode (dBA) using the MODE button.
2. Set the response time to SLOW (see the Programming section)
3. Insert the 407355 microphone into the microphone cavity of the calibrator.
4. Turn the calibrator ON for 94.0 dB and adjust the CAL screw on the 407355 so that the LCD
display matches the calibrator output signal.
Note: OSHA regulations consider it good business practice to calibrate before and after each use.
A yearly calibration is recommended to maintain measurement accuracy.

Erase the Memory

If the low battery mark is flashing or all of the Dosimeter survey memory E1 through E5 has been
filled, the datalogging function will not operate.
The memory must be cleared.
Clear memory in a single Event bank:
If data is present in a single bank, the bank ID flashes.
To erase data in a specific bank, press and hold the RESET button until the bank ID stops flashing.
Clear all of the memory in the whole meter:
To clear the memory in the whole meter for SLM data only, turn the meter off then hold down the
RUN key and turn on the meter.
E-EP will appear in the display to indicate that all memory data has been cleared, release the RUN
key.
To clear Dose data, erase each individual bank.
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