Rockwell Automation 9301 Series RSView32 Users Guide - Manual (Page 236)

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RSView32 User’s Guide
2. Click a button to specify a log trigger and fill in any additional
information. See the topics below for information on the different
types of log triggers.
Logging periodically
Periodic logging is used to take a snapshot of all tag values at a
particular point in time. You can use the dBASE IV (narrow), dBASE
IV (wide), or ODBC storage format for periodic logging. For periodic
logging to dBASE IV files, the dBASE IV (wide) file format is most
efficient for storing the data.
1. Click Periodic.
2. In the Interval field, type a time and click a time unit to specify
how often tag values will be logged. All tags in the model will be
logged each time this interval expires.
Do not set the interval faster than the scan class rate, OPC ® update
rate, or DDE poll rate, or you will log redundant data. For
information about scan classes, see “Scanning for new tag values”
on page 2-17. For information about update rates see “Scanning
for new tag values” on page 3-17.
You can change the periodic log rate at runtime, as described on
page 7-43. However, the runtime change affects the current data
log session only. When you stop and restart the model, RSView32
uses the log rate you set up here.
Logging on change
On-change logging is used to log only tags whose values have
changed, when the change occurs. You can use the dBASE IV
(narrow), dBASE IV (wide), or ODBC storage format for on-change
logging. For on-change logging to dBASE IV files, the dBASE IV
(narrow) file format is most efficient for storing the data. The dBASE
IV (wide) format is not recommended because records are logged for