Casella CEL Indoor air quality monitor - Manual (Page 39)

Specification
Dynamic Range 70 dB
Typical Frequency Range Within +0.5 and -3 dB
between 10 Hz to 25 kHz
Measurement Ranges A LO 30 - 100 dB(A)
A HI 65 - 135 dB(A)
C LO 30 - 100 dB(C)
C HI 65 - 135 dB(C)
Accuracy ±1 dB
Microphone Type CEL ¼ inch pre-polarised electret
Time Weightings F (fast) 125 ms
S (slow) 1 s
I (impulse) 35 ms rise time
1.5 s decay
MAX (hold) Holds readings of
F, S & I with
<1 dB/5 min
decay.
DC Output from 3.5 mm 3 pole
coaxial socket in bottom of the
instrument case between ring
and ground Log signal: nominal 25 mV/dB
(offset by approx. 4 to 5 V) and
not exceeding 6 V
AC Output from 3.5 mm 3 pole
coaxial socket in bottom of the
instrument case between pin
and ground Conditioned signal: 7.25 V RMS
for FSD
Operating Temperature -10 to +50
o
C
Storage Temperature -20 to +60
o
C
Sensor Specifications
Page 39 of 42
MICROTHERM indoor air quality &
WinIaq Application Software - User Manual