Specification 6.1 general – Casella CEL CEL-450 User Manual
Page 63

6.
SPECIFICATION
6.1 General
Standards:
The CEL-450/490 series are self contained sound level meters
designed to comply with the following international standards.
IEC 61672-1 2002-5 (Electroacoustics - Sound Level Meters)
Group “X” instruments, performance class 1 or 2 as relevant to
the instrument model.
IEC 60651 197, IEC 60804: 1985, ANSI S1.4: 1983, ANSI S1.
In addition, for Octave and Third-Octave band versions (B and C
models) the filters comply with:
EN 61260: 1996, Class 0 and ANSI S1.11, Order-3 Type 0C.
Octave Filters: 11 bands with centre frequencies from
16 Hz to 16 kHz (B and C models).
Third Octave Filters: 33 bands with centre frequencies from
12.5 Hz to 20 kHz (C models).
Narrow band filters may also be pre-weighted with A, C or Z
frequency weightings.
Measurement Ranges:
Single 0 -140 dB range: Linear operating range defined by
the self-generated noise of the instrument only.
Peak levels: A, C and Z available to 143 dB.
Dynamic range: Typically 123 dB.
Level Detector: Digitally derived true root-mean-square (RMS)
detection, 0.1 dB display resolution.
Electric Noise Floor:
Noise floor with 18 pF dummy microphone: Typically
16.5 dBA.
Total inherent Noise including microphone thermal
noise at 20
o
C:Typically <18.5 dBA.
CEL-450/490 Operators Handbook - Page 63
Specification