You are going to create a measure for the expected output of the Boiler. The Boiler has been designed to produce 14.5 metric tons per hour.
Drag the “Hourly” icon from the Flow Zone onto the “Steam” metric.
Rename the new Manually Entered measure to “Steam Production Rating”. Notice the icon indicates the Measure Type (i.e. manual).
Double-click the new measure and edit the general properties as follows:
Expand the “Retrieval” section. Notice that the “Retrieval” section is different for a Manually Entered Measure compared to a Retrieved Measure. A Manually Entered Measure is configured to have a “Default Value”. Just like an hourly Retrieved Measure, Flow will generate an hourly time period for an hourly Manually Entered Measure. The value for each of these time periods depends on the “Default Value” setting.
Let’s discuss the “Default Value”: options
- Set to previous value – Flow will set a new time period’s value to the value of the measure’s previous time period. An “Initial Value” setting tells Flow what the first time period’s value will be set to. This option is useful for calculation factors you may want to change over time, but not too frequently.
- Set to 0 – Flow will set a new time period’s value to 0.
- Set to null – Flow will set a new time period’s value to a null (empty) value. This option is useful when creating a measure for an instrument or value that needs to be inserted manually by a person every time period (e.g. daily electricity reading from an external meter).
- Set to measure value – Flow will set a new time period’s value to the value of another Flow measure at the same point in time. This option is useful when you need to, for example, set an hourly measure’s value to that of a weekly measure.
For your new “Steam Production Rating (tons/hr)” measure, set the “Default Value” setting to “Set to previous value” and the “Initial Value” setting to 14.5 as follows:
Deploy the new measure and confirm that it is running and producing a value of 14.5 tons/hr every hour: