Svantek SV 971A, Руководство пользователя

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SV 971A User Manual
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confirm the calibration results. A measurement cannot be in
progress while the automatic calibration is being performed.
Note: SV 971A has two different dynamic ranges
– Normal and Low. In the SLM functions
(Level Meter, 1/1 Octave, 1/3 Octave, RT60 and STIPA) both ranges can be used for
measurement, but in the SEM functions (Dosimeter
, 1/1.&Dose , 1/3.&Dose)
– only Normal
(see Chapter 4.6 and 11.4 ). But in case of calibration, it does not matter which function and
which range is selected.
In the Simple user interface, the Calibration list
comprises positions enabling calibration with the use of
the sound calibrator (
By Measurement ), checking and
erasing previous calibration records ( Last Calibration ,
Calibration History , Clear History ), adding current
calibration results to the logger file ( Post Calibration ).
<ENT>
In the Advanced user interface, there is additional position in the Calibration list
- Auto Calibration , which allows you to switch on/off the auto calibration
function.
Note: It is advised to perform calibration of the instrument each time before the measurements
begin. A single calibration at the start of each day is usually sufficient for most regulations.
Note: The calibration factor is always added to measurement results and measurement range
limits of all measurement functions.
Note: The recommended factory calibration interval is 12 months for instruments to be
confident in their continuing accuracy and compliance with the international codes. Please
contact your local Svantek distributor for further details.
Note:
It is possible to perform so called “By Sensitivity” calibration by setting the calibration
factor with the use of special command
– see Appendix A.
3.2.1 Calibration
– By Measurement
To calibrate the instrument:
1. Set the calibration level ( Cal. Level )
– see Appendix C, Chapter C.1, par.
Calibration.
2. Attach the sound calibrator (SV 36 or equivalent 114 dB/1000 Hz) carefully
over the microphone of the instrument.
Note: It is also possible to use an electro-mechanical pistonphone, which generates a signal
(ca 124
dB) or different type of acoustic calibrator dedicated for ½” microphones. It is also
necessary to switch the instrument Range to the Normal level.
3.
Switch on the calibrator (if the used calibrator doesn’t have auto run function)
and wait ca 30 seconds for the tone to stabilise before starting the calibration
measurement.
4. Start the calibration measurement by pressing the <Enter> or <Start> key.
The calibration delay time is set to 3 seconds. While waiting for the start of the
measurement the
Delay is counting down on the display.