Trends Guide - SOURCE Optional Values (Using TrendSpec to Produce Ad Hoc Trends)

SOURCE Optional Values

Specify any optional SOURCE values after the SOURCE Mandatory Value in a TrendSpec definition. Remember to include a comma at the end of the mandatory value before listing any of these optional values. Include a comma between each optional value’s definition.

The optional SOURCE values are equivalent to the properties that you can specify using the Edit Source window on a Pre-Configured Trend. For further information on these properties, see Configure a Trace.

The optional values that you can specify within the SOURCE section are:

SOURCE Optional Values
Identifier	Value Type	Comments
AggregateId (Only applicable if the TRACE’s <Data Mode> is ProcessedHistoric.)	Long	Use to specify that algorithm that ClearSCADA uses to process the source’s historic data. The values that you can specify vary, depending whether the TRACE’s Interval identifier is set to PerPixel or a specific time period (see Supported AggregateId Values). Example: AggregateId =10 (results in a trace that depicts the maximum value during each resample Interval.)
Multiplier	Real	Use to define the amount by which ClearSCADA multiplies the data values. The scaled values form the source of the trace. Example: Multiplier = 1.500000 Alsosee Enable Users to Specify Which Traces to Include on an Ad Hoc Trend.
ShowAlarmLimits	Boolean	Use to specify whether alarm limits are displayed within a trend, in addition to the trace that indicates the processed data. By default alarm limits are not displayed. Example: ShowAlarmLimits = True To show alarm limits on a trace. `SOURCE( Point1.Historic',Aggregate = 'Interpolated'), Style = Line, ShowAlarmLimits = True )` If a trace has multiple sources, (see Multiple Source Traces) it is advisable to set the alarm limits to False. Also see Use TrendSpec to Show/Hide Alarm Limits
XOffset (Only applicable if the TRACE’s <Data Mode> is RawHistoric or ProcessedHistoric.)	Integer or String	Use to define a time offset for the trace. If required, use the XOffset to display source values from a different time period to that indicated by the x-axis. Either specify the XOffset as an integer, whereby the value has to be in seconds Example: XOffset = 300 (for the XOffset to be 300 seconds, or 5 minutes) or as a string, whereby the value has to be specified in the OPC Time Format. Example: XOffset = ‘5M’
YOffset	Real	Use to define the position of the trace values on the y-axis. Example: YOffset = 0.200000 Also see Enable Users to Specify Which Traces to Include on an Ad Hoc Trend.