GHM DeltaOHM HD2010UC, Operating Manual

Page: 76 / 134

HD2010UC
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V4.2
sponse, it’s necessary to set the specific parameter Menu >> Calibration >> Shield >> WME.
With this setting applied, HD2010UC sound level meter with HD WME protection, fully com-
plies to type 1 specifications according to IEC 61672 standard; in such configuration, when used
in vertical position, the sound level meter is able to measure accurately environmental noise from
above (0° incidence) like for example the noise generated by aircraft overflights.
When parameter Menu >> Calibration >> Shield is set to WME and microphone acoustic re-
sponse ( menu Calibration >> Mic.Resp.Correction) is set to RI, it’s applied a frequency spectral
correction to obtain a flat frequency response in a diffuse field. Using this setting the
HD2010UC sound level meter with HD WME outdoor protection mounted in vertical position, is
suitable for measurements of environmental community noise due to noise sources on the ground
(road traffic noise, railway noise…).
For more information on spectral correction applied to HD2010UC sound level meter when
used with HD WME outdoor protection, please refer to UC52 microphone user manual.
Self-generated Noise
The intrinsic noise, measured replacing the microphone with the capacitive adapter,, ,is shown in
the following tables according to the different frequency weightings, either for
RMS level or
peak level measurements:
Input Gain
[dB]
Intrinsic noise [dB]
LpA LpC LpZ LpkC LpkZ
0
50 49 53 61 65
10 40 39 43 51 55
20 31 32 36 45 48
30 26 30 33 43 45
40 24 29 33 43 45
Linearity range
The lower limit of the linearity range, was calculated as the maximum between the upper limit
decreased by 80dB and the self-generated noise increased by 7dB. The upper limit is equal to
141dB with a input gain equal to 0 dB and decrease by 10 dB for every 10 dB gain increment.
The linearity range is almost independent of frequency in the 31.5 Hz … 12.5 kHz interval, and
it is shown in the following table according to the input gain:
Input Gain [dB] Parameter
Lower Limit
[dB]
Upper Limit
[dB]
0
LpA 60
141 LpC 60
LpZ 60
LpkC 68
144
LpkZ 72
10
LpA 50
131
LpC
50
LpZ 50
LpkC 58
134
LpkZ 62
20
LpA 40
121 LpC 40
LpZ 43
LpkC 52
124
LpkZ 55