otometrics MADSEN Midimate 622, Руководство пользователя

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12. CALIBRATION
The calibration of the MIDIMATE 622 is stored in a non-volatile memory
EEPROM type, which requires no battery backup. In order to prevent
unintentional alteration of calibration this function must be enabled
separately before any changes can be made to calibration (please refer to
Service Manual). Calibration Stored
in Memory
Calibration should be performed annually by suitably qualified personnel,
using the appropriate equipment.
Your MIDIMATE 622 is dispatched from the factory in Denmark together with
a Test Report (Calibration Certificate). The Test Report specifies which
transducers have been calibrated (i.e. those which have been supplied
together with the instrument), according to which standards, and what
equipment was used for calibration. Results are listed for each transducer at
all standard frequencies.
In general, the instrument is calibrated in dB HL using the stated reference
equivalent thresholds, which are related to sound pressure levels (db SPL =
dB re 20
%
PA), and force levels (dB re 1
%
N).
Note that calibration has only been performed on the supplied
transducers! If you wish to use any other transducer for testing with
the MIDIMATE 622, please contact your local distributor first.
12.1 ERROR CHECK
To ensure accurate measurements, all calibration locations are checked at
power-on time and whenever a new location is accessed, i.e. when changing
frequency or input/output routing. Calibration Check
This means that if any errors are detected by the self-test, the error is
indicated on the display. Furthermore, if a calibration error is detected during
operation of the audiometer, then it is also indicated on the Test Mode display
by blinking “Err” where “dB” is normally displayed. Calibration Errors
12.2 CALIBRATION REFERENCE
After power-up, the audiometer displays the calibration reference currently
valid for the instrument as well as the date and operator ID of the calibration
currently installed. Power-Up
FREE FIELD
Free Field
Fixed output level for all signal sources (must be
calibrated on site).
MIDIMATE 622 OPERATION MANUAL 12. Calibration
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