The instrument displays a new screen:
➢
Check that the reference value
Ref
: is equivalent to the value of the used
calibrator and to the value of free-field correction (C.Cl) (0.0 dB for the sound
level meter).
➢
Put the operating calibrator on the microphone.
➢
Put the cursor with the arrow keys on
LCF.
The instrument automatically adjusts the gain of the chain to get the coincidence of the
displayed levels in
Ref
and
LCF
.
➢
Once the measurement is stabilized,
“Cal.”:
press
OK
key to validate.
The correction value of the gain and the calibration date are memorized and visible for the next calibration.
➢
Press
Esc
key to quit this function.
Modification of the reference value:
The reference value preset during the manufacturing process shows that we use calibrator with rated value of 94 dB at 1000 Hz.
If the proposed reference is not the one of the available calibrator, follow the instruction below:
➢
Move the cursor on
Ref
. With arrow key adjust to the desired value dB per dB with the scrolling knob key .
This new value is memorized until the next change.
This new value must be set between 70 dB and 130 dB.
13.4Maintenance
The sound level meter conception allows a reduced maintenance which consists in changing batteries and cleaning the instrument with
a slightly cloth. A particular attention must be paid to the microphone sensor, which is the element the most sensitive of the
metrological chain.
13.5Regular checking
Like most measuring instruments, it is strongly recommended to regularly control and calibrate the sound level meter. Return to the
manufacturer each year will provide necessary metrological traceability.
13.6Replace the battery by a batteries pack
In case of impossibility to load the battery, it is sometimes unavoidable to replace it by a batteries pack. The batteries life will decrease
from 8 to 10 hours in continuous operating.
➢
Turn off the sound level meter.
➢
Remove the battery (do not forget to disconnect the cable).
➢
Connect the battery respecting its insertion direction (mechanical keying of security).
➢
Slide the battery into the housing.
➢
Close the back hatch.
53
Direction for use and maintenance of the sound level
meter
Ref : dB
C.Cl dB
LCF dB
Corr. dB
CALIBRATION
94.0
0.0
94.0
0.5
05/10/2011
Ref : dB
C.Cl dB
LCF dB
Corr. dB
CALIBRATION
94.0
0.0
94.0
0.5
05/10/2011
Cal.
Note :
This correction can not exceed
+/- 1.5 dB (class 1) or +/- 2 dB (class 2)
. If the correction exceeds
+/- 2 dB
, the coincidence values in
Ref
and
LCF
is not obtained. Reasons of this difference shall be
identified (defective microphone, level value of the calibrator not adapted...).
