Understanding Flow Total

The application sums the specified values from assigned points in the analog, rate, gasmeter, or gasquality tables, or a flow total rate from the flowTotalConfig table. The sum of the values is stored in the flowTotalConfig record, which can maintain up to four separate summations simultaneously. Each summation is stored in a calculation element.

Flow Total Data Sources (flowTotalJoin) records link together the points used to arrive at the sums of the flowTotalConfig record's elements.

Note: The system can accommodate up to 500 flow total points, by default. Systems may be installed with a larger or smaller capability.

The module calculates the flow total in a priority order.

Note: There are 65,535 flow total priority levels.

A continually running monitor process totals the flow rate of the contributing points into each flowTotalConfig point at a configured frequency.

Note: Both the minimum frequency and the default frequency is once every 15 seconds. The monitorFlowTotal process contains an option for setting a different execute cycle frequency.

Staling of FlowTotalConfig Points

The system sets a flowTotalConfig point to stale if:

• Any of the contributing telemetered points are:

  • Stale

    OR

  • In manual mode

• The source paths for all calculation elements are either blank or disabled.

• The source path is invalid.

• All calculation elements in the flowTotalConfig record are disabled.

  Note: For the last three stale conditions above, the application also zeros out the calculated values.

Configuration Procedure

The procedure for configuring the Flow Total application is as follows:

1. Create a main flowTotalConfig record to store the point totals, and configure the properties of the calculation elements whose values you want the Monitor process to calculate.

2. Create one or more flowTotalJoin records for the flowTotalConfig record created in Step 1. The number of records created depends on the nature of the calculations you want the Monitor process to perform (refer to Calculation process).