Algorithm Makes Trends property
The
Make Trends property determines if an algorithm generates a constant value or a trend. These blocks have a Make Trends property: Interval Count, Value Duration and the four constant blocks, Boolean, Enum, Numeric and String. All default to false, which configures each block to return a constant value.
Figure 64. Algorithm illustrating Makes Trends property
When a Makes Trends property is false on the algorithm Property Sheet, the framework does not process any trend requests. A value of true allows the framework to process both value and trend requests using the algorithm.
TIP: Since analytic requests can be configured as either value or trend requests when the
Makes Trends property is set to true, if a trend request (chart or table) result is empty (no data displayed), verify that Makes Trends is not set to false on the algorithm Property Sheet.
Some algorithm blocks, like a Numeric Constant, do not map to a history in the station’s database. These blocks may provide a value when the algorithm processes a trend
request, but the block does not actually output a trend to pass to downstream linked blocks. If you link this type of block’s
output to the input of a downstream block that requires a trend, you must set the Makes Trends property true.