Casella CEL CEL-63X - Manual (Page 79)

CEL-63x Environmental & Occupational Noise Meter
79 Casella CEL
without the wind screen, then you must set the calibration level to
113.88 dB. You must round this value to 113.9 dB.
o Calibrator level 113.98 dB
o Correction –0.1 dB
o Calibration level 113.88 dB rounded to 113.9 dB
If you use a Cirrus CR:515 calibrator and the certified output from the
calibrator is 94.04 dB, and you intend to use the instrument with the
wind screen fitted, then you must set the calibration level to 94.04 dB.
You must round this value to 94.0 dB.
o Calibrator level 94.04 dB
o Correction 0.0 dB
o Calibration level 94.04 dB, rounded to 94.0 dB
Refer to section 3.4 “ Calibrating the instrument ” on page 13 for instructions to
set the calibration level and calibrate the instrument.
10.2 Response characteristics
Table 7. Casella CEL-63X with CEL-251 Microphone Free Field response with and
without Wind Screen
Nominal
Frequency
Actual
Frequency
0 Degree
Free Field
Response
0 Degree
Free Field
Corrections
Effect of
Wind Screen
0 Degree
Free Field
Response
with wind
Screen
0 Degree
Free Field
Corrections
with Wind
Screen
Expanded
uncertainty
of
Corrections
(k=2)
Hz Hz dB dB dB dB dB dB
250 251.19 -0.2 0.2 0.0 -0.2 0.2 0.16
315 316.23 -0.2 0.2 0.0 -0.2 0.2 0.16
400 398.11 -0.2 0.2 0.0 -0.2 0.2 0.16
500 501.19 -0.2 0.2 0.0 -0.2 0.2 0.16
630 630.96 -0.1 0.1 0.0 -0.1 0.1 0.17
800 794.33 -0.1 0.1 0.0 -0.1 0.1 0.18
1000 1000.00 -0.1 0.1 0.1 0.0 0.0 0.19
1250 1258.92 0.0 0.0 0.1 0.1 -0.1 0.19
1600 1584.89 0.0 0.0 0.2 0.2 -0.2 0.20
2000 1995.26 0.0 0.0 0.2 0.2 -0.2 0.21
2240 2238.72 -0.1 0.1 0.3 0.2 -0.2 0.21
2500 2511.88 -0.2 0.2 0.4 0.2 -0.2 0.21
2800 2818.38 -0.1 0.1 0.4 0.3 -0.3 0.22
3150 3162.27 0.0 0.0 0.5 0.5 -0.5 0.22
3550 3548.13 0.1 -0.1 0.5 0.6 -0.6 0.23
4000 3981.07 -0.2 0.2 0.6 0.4 -0.4 0.23
4500 4466.83 -0.1 0.1 0.6 0.5 -0.5 0.25
5000 5011.86 -0.1 0.1 0.6 0.5 -0.5 0.26
5600 5623.40 -0.3 0.3 0.5 0.2 -0.2 0.28
6300 6309.56 0.1 -0.1 0.4 0.5 -0.5 0.29
7100 7079.45 -0.3 0.3 0.2 -0.1 0.1 0.32
8000 7943.27 0.0 0.0 0.0 0.0 0.0 0.35
8500 8413.94 -0.1 0.1 -0.1 -0.2 0.2 0.38
9000 8912.49 0.0 0.0 -0.1 -0.1 0.1 0.41
9500 9440.59 -0.1 0.1 -0.2 -0.3 0.3 0.44