Casella CEL CEL-414 - Manual (Page 19)

3.8Batteries & Auxiliary
Power Supplies
Caution
DO NOT use any battery with
damaged insulation or
sleeving. DO NOT connect a
charger unit to the auxiliary
socket. If rechargeable nickel
cadmium cells are used, they
must be removed from the
instrument for recharging.
These instruments are designed to oper-
ate with a set of four manganese alkaline
batteries (IEC Type LR6) like those sup-
plied. Depending on duty cycle, this type
of battey can give up to 15 hours of op-
eration. Rechargeable nickel cadmium
cells may be employed, but have a
shorter operating period. Zinc carbon bat-
teries are NOT suitable.
The end of battery life occurs when the
output falls to approximately 3.2 V, at
which point the “LOW BATT” message
is shown on the display. Approximately
30 minutes later the instrument will be
switched OFF automatically. This avoids
discharging the batteries to a point
where they would cause damage if the in-
strument was inadvertently left ON.
Once the automatic switch off sequence
has occurred, the instrument can be re-
started only by replacing the batteries
and operating the ON-BAT-OFF switch.
As a leakage of battery fluid can cause
considerable damage, remove any leak-
ing or unserviceable batteries as soon as
they are discovered. The batteries should
also be removed when the instrument is
to be stored for a prolonged period (or
powered from an external supply). Incor-
rect installation, handling, operation, and
disposal of batteries can be dangerous.
Follow the battery manufacturers recom-
mendations, and if in doubt, seek the ad-
vice of a specialis. When measurements
900086
Potentiometer Range:
Measuring
0
50
40
30
20
10
Rec. No.
Date:
Sign:
dB. Rectifier: Lower Lim. Freq.: Hz.Wr. Speed: mm/sec.Paper Speed mm/sec.
dB
10 20 Hz 50 100 200 500 1 2 kHz 5 10 20 40D
A
Lin A
B
B
C
C
Lin
100
10dB
CEL-266
1kHz
Oct Filter
Typical
Response
Object
Figure 5: Typical octave filter response curve
General CEL Sound Level Meters Handbook - Page 15