How to
Displaying the History of a Trend Log Record
You show the history of a trend log record, such as the original value as well as edits, through the trend log list.
The trend log list numerically displays the records of a trend log or an extended trend log. The records of the trend log can be processed by a calculation method before they are presented in the trend log list.
The trend log list can only display one trend log at a time and must be manually refreshed to display recently recorded values.
You can manually add records to a trend log list for any type of trend log.
Time Zone Modes in a Trend Log List
In a trend log list, you can present the records of a trend log in different time zones: local time zone, EcoStruxure BMS server time zone, and UTC time zone.
For more information, see Time Zone Modes in a Trend Log List .
Calculation Methods
Use a calculation method to process the records of the trend log before presenting them in a trend log list or a trend chart. The original records in the trend log are not affected by the calculation method. The calculation method is applied to the trend log records grouped by a specific time interval.
For more information, see Calculation Methods .
Period Timestamps in Trend Charts and Trend Log Lists
When a calculated value for a period is presented, the middle of the period is used as the timestamp.
Example:
The calculated value for the period 8:00-9:00 is stamped 8:30. If there is a value at 9:01, the next period is 9:00-10:00, which is stamped as 9:30. The full period may not have passed yet, but the value can be presented even if parts of the period are in the future.
Temporary Trend Log Lists
To display a trend log without creating a new trend log list or trend chart, the trend log can be displayed in a temporary list or chart.
For more information, see Temporary Trend Log Lists .
Floating Point Values NaN, INF, and -INF
In the EcoStruxure BMS software, the floating point values “Not a Number”, positive infinity, or negative infinity may be displayed in the Basic property tab, in a trend log list, or a trend chart.
For more information, see Floating Point Values NaN, INF, and –INF .
In WorkStation, in the System Tree pane, select the trend log list you want to show.
In the Trend log list , right-click a record, and then click Show history .
Click Close .
The dialog box displays all old values and which user that edited the record.
Editing or Commenting a Trend Log Record
Trend Log Lists
Trend Log List Context Menu