Casella CEL CEL-414 - Manual (Page 5)

These instruments are a re-interpretation
of the classic full specification sound
level meter.
The CEL-266/3, CEL-275/3, CEL-414/3
and CEL-493/3 satisfy the requirements
of IEC 651: 1971 Type 1I for precision
impulse sound level meters (and ANSI:
S1.4-1983, Type S1 when used with an
“R” type random incidence microphone).
The CEL-266/3, CEL-275/3 and CEL-
493/3 also satisfy the requirements of
IEC 804 Type 1 for integrating sound
level meters.
The CEL-328/3 and CEL-383/3 satisfy the
requirements of IEC 651: 1971 Type 2I
for impulse sound level meters, ANSI:
S1.4-1983, Type S2 for sound level me-
ters and (except for CEL-328/3E) also IEC
804 Type 2 for integrating sound level
meters.
All of these instruments and versions can
measure sound pressure levels in the
range from 20 dB(A) to 140 dB(A) at fre-
quencies between 3.5 Hz and 20 kHz
with the microphone supplied, and up to
70 kHz with a suitable microphone.
When used with the CEL-4391 Attenu-
ator Pad (supplied) the CEL-493/3 is able
to measure sound levels up to 150 dB(A).
The instruments use modern microproc-
essor and component integration to pro-
viding all the traditional measurement
facilities in a compact and easily handled
unit.
Well proven concepts and methods have
been employed in their design and con-
struction so that the most commonly
used acoustic measurements can be per-
formed. They provide a continuous indica-
tion of the instantaneous sound pressure
level SPL in both analog and digital for-
mats on a liquid crystal display. Displays
showing the measurement duration and
maximum value may also be selected.
The CEL-266/3 and CEL-328/3 contain 10
built-in octave filters with centre frequen-
cies between 31.5 Hz and 16 kHz. These
filters satisfy the requirements of IEC
225 and ANSI S1.11-R1975 Class 2.
With the exception of the CEL-414/3 and
the CEL-328/3E, all versions also calcu-
late the equivalent continuous level L
eq
(plus L Tm3 and L Tm5 , or L OSHA and L DOD )
and the sound exposure level SEL at the
same time. The CEL-328/3E calculates
only the octave filtered L
eq values.
This Operator’s Handbook covers all of
the instrument types and versions shown
below.
CEL
Type
European
Versions
American
Versions
Oct.
Filter
A B
I/face
C D
I/face
E
328/3
Type 2
X X X X
383/3
Type 2
X X X X
266/3
Type 1
X X X
275/3
Type 1
X X X X
414/3
Type 1
X
493/3
Type 1
One single version, with European
software plus a built-in interface
The CEL-493/3 plus B and D instrument
versions have a built-in CEL low power
interface, which allows them to be con-
nected to one of the data logger/printers
1. INTRODUCTION
General CEL Sound Level Meters Handbook - Page 1