AccuEnergy Acuvim II, Руководство пользователя

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Note:
If the logging timer is disabled, the first recording sector will be erased
when the log is full. Therefore, user should not read the whole log when the
used record numer is near to the max record number. Under this condition,
user should read the "Used Records" field and compare it to the previous "Used
Records" field from the last reading before retrieving the information and
reading the window.
If the current "Used Records" field is greater than the "Used Records" field from
the last reading and if the "Offset" field is less than the difference between the
current and previous "Used Records" field, the first sector has been erased and
the difference between the "Used Records" field should be subtracted from the
recording number.
If the "Offset" field is greater than the difference between the current and
previous "Used Records" field, the "Offset" number should be subtracted from
the recording number.
To avoid this situation, user should read the log before it is almost full.
For example: Data logging 1 has 3 sectors and each has 448 records, and
the total records are 1344. If you press the "Read All" button when the
"Used Records" number is at 1340 and if the first sector is erased before the
information is transferred to the computer, the data stored in this sector is
erased permanently and cannot be retrieved. If the records from the first sector
can be retrieved before it gets erased, the new value of "Offset" will equal to the
original "Offset" field minus the value of the difference between the current and
previous "Used Records" field.
Data logging opration examples
The following example illustrates a data logging opertation. The example
makes the following assumptions:
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