Norsonic nor140, Instructional Manual, Page: 81 / 220

63
Norsonic Nor140
Instruction Manual
63
Norsonic Nor140
Instruction Manual
Memory handling
The instrument has a large built-in, non-volatile
memory which can hold large amounts of measured
data and measurement setups. These data can be
transferred to a remote PC for further processing and/
or printed out.
In addition, the data may be stored on a SD-card.
Cards up to 8GB may be used, , but we recommend
Industrial Grade cards up to 2GB since they are faster
and more reliable than the inexpensive standard cards
you can get for digital cameras and cellular phones.
Please note that no file in the system may exceed
the 4 GB limit. This file size is only possible to achieve
with audio recordings, and it corresponds to a record-
ing of approximately 8 hours using 48 kHz sampling 24
bit resolution or 92 hours of 12 kHz 8 bit resolution.
Memory structure
The memory structure of the Nor140 is quite similar to
that of a PC. They both have folders and files. Howev-
er, simplicity is a keyword in the Nor140 memory han-
dling, the folder available for storage has the name of
today’s date and the files are numbered consecutively
in ascending order as they are stored, starting at 0001.
Internal memory size
The available internal memory for storing of measure-
ments is approximately
25 megabytes
. This is a num-
ber which says more or less nothing to most people
since it reveals nothing of the number of bytes required
to store the measured values etc. Let us therefore pro-
vide a few examples.
Example 1.
The internal memory can hold more than
50 000 global measurements with all available global
functions and distribution when frequency analysis has
been deactivated.
Example 2.
The memory can hold more than 12 000
global measurements with all available global functions
and distribution when frequency analysis has been
activated.
Example 3.
The memory can hold approximately
1 2 500 000 samples of L(t) when only one function is
logged (requires the enhanced profile extension). This
corresponds to more than 300 hours logging with 0.1
s resolution!
Example 4.
The memory can hold more than 450 000
samples of L(t) when all 28 functions are logged in
profile (requires enhanced profile and multiple time
constants). This corresponds to more than 125 hours
with a resolution of 1 s.