Casella CEL CEL-440 User Manual

Page 24

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Operation

Press

Display Shows

Comments

5. Save the

new

Calibration

setting

The settings are stored as

the current calibration

!

.

When the calibration check is complete, press

once to obtain a

Measurement screen or twice to obtain the Main menu that gives
access to all settings and stored data.

c-05

dB

13Jan98 11.Ø7

Last Cal.

L

ZF

MENU

Table 1: Calibration Levels

4

Accuracy Microphone

Type

Directional

Response of

Microphone

Acoustic

Calibrator

Calibration

Level

Type 1

Instruments

CEL-250

Free Field (IEC)

CEL-284/2

114.0 dB

Random Incidence (ANSI) CEL-284/2

113.8 dB

Type 2

Instruments

CEL-485

Free Field (IEC)

CEL-282

CEL-284/2

113.6 dB

Random Incidence (ANSI) CEL-282

CEL-284/2

113.6 dB

Note 3: Firmware V 2.0 introduced the ability to include settings from the current

calibration together with settings saved from the calibration made before the run

when a hard copy of the run is printed. This allows calibration settings from both

before and after a run to be included in the printout from the run.

Earlier firmware printed (and included) only the calibration settings current at the

start of (i.e. before) the run.

When no calibration has been performed after a run, the current settings printed

will be the same as those from before the run.

However, if data from a run is printed some time after the run was stored and the

instrument has been re-calibrated in between, the hard copy will include the most

recent calibration settings as current.

Note 4: These levels may also be subject to further correction as follows:

(a) When a traceable calibration certificate is available for the acoustic calibrator

and/or the sound level meter.

(b) To compensate for atmospheric conditions as described in the calibrator

instructions.

Page 24 - CEL-440/480 Operators Handbook

Preliminary Operations

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