Casella CEL CEL-281 - Manual (Page 65)

(yellow key: enables results to be calculated with different
threshold levels)
This key is active only while %Dose, Projected %Dose or L AVG
values are being displayed.
Pressing this key shows the current threshold level on the main
display, while pressing the key again selects the next valid level
from a series of up to five threshold levels for use in the calcula-
tion.
Then pressing the relevant working area key again returns the
display to whichever parameter was being inspected, so that
the results calculated with the new threshold level can be seen.
Refer to Table 1 in Section 2.2 for details of valid threshold lev-
els. These may include 70 dB, 75 dB, 80 dB, 85 dB and 90 dB.
3.4 Memory Functions
The CEL-281 memory is made up from a 32 k EPROM which contains
control and processing programs, and a 32 k RAM that stores noise infor-
mation.
The most recently used values of the following parameters and data will
be stored while the instrument is switched OFF, and are available for
use or display as soon as the instrument is switched ON again.
Dose Q,
L
AVG Q,
Threshold value,
Criterion value,
Frequency weighting (A or C),
Earliest stored time and date that 200 Pa level was exceeded,
Latest stored time and date that 200 Pa level was exceeded,
Calibration coefficient,
Occurence of overload,
Over range count,
CEL-281 Operator's Handbook - Page 57
How It Works