Omron CX-Supervisor, Руководство пользователя

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Data Log Editor SECTION 11 Data Logging
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The functionality of the Items is determined by their expression. If the
expression is a single point name, the item is shown as the same type as the
point as configured in the point editor, i.e. memory, input, output or input/
output. If the expression contains calculations, constants and/or multiple point
names, the item is shown as a script calculation.
11-2-2 Adding/Editing Data Set Properties
The Add/Modify Data Set properties dialog box opens when either the Add
Data Set or the Edit (an existing Data Set) option is selected from the menu.
11-2-2-1 Data Set Properties
The Data Set Name field enables the Data Set to be referenced with a
meaningful description both in the Workspace view, and also from the script
language. It also forms the prefix for the file name. A maximum of 26
characters is allowed.
The Period fields allow a period to be entered in Hours, Days, or Months and
defines the period of data to be grouped into a single file. For example, if the
Period is set to 1 month, any data logged for the current month is saved to the
same data file, even when the system is stopped and restarted. When logging
spans a Month boundary the data file is closed, and a new file started and
given sequential file name. This allows easy archiving and backup of the
logged data. The start of a new data file is always synchronised to a natural
boundary, e.g. for months - the 1st of the month, for days - 24.00 hours and for
hours - on the hour.
The No. Of Files to Keep entry determines the maximum number of data files
that are to be kept. When the number of files kept has reached the value
entered, as each new file is created the oldest file is deleted. For example, to