HBK 4231, User Manual

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Influence of Ambient Temperature
12 Sound Calibrator Type 4231
User Manual
3.2 Influence of Ambient Temperature
Under normal conditions, the influence of changes in ambient
temperature on the sound pressure level produced by the calibrator is
so small that you can ignore it.
You can see the effect of ambient temperature changes in Fig.3.2.
These are mainly caused by variations in the reference microphone’s
sensitivity. The electronic compensation corrects for the main
influence of temperature on the microphone’s nominal sensitivity, and
the deviation is caused by the variation from this nominal value.
Fig.3.2 Typical calibration uncertainty at 101.3 kPa due to variation in ambient
temperature
930278/5
0.05
0
– 0.05
Calibraon
Deviaon
in dB
Calibraon
point
– 0.045
0 10 40 30 50 – 10
IEC 60942
Specificaon range
0.045
20
Ambient
temperature
in °C