Rate table

Rate records are used to represent a rate or accumulated quantity. Rate records are located in the rate table and are configured using the rate Row Edit dialog box.

In addition to basic accumulated quantities rate records can be configured for:

• Conversion of a raw telemetry rate value into a value in engineering units (EGUs).

• A first order smoothing filter applied to the raw rate value.

• The application of scaling factors to a telemetry pulse input representing an accumulated quantity (for example, m3 or kWh).

• A rate calculated from the quantity increment over time, taking into account accumulated quantity rollover.

• An accumulated quantity calculated from a rate multiplied by the time period during which the rate was constant.

• A software accumulated quantity calculated from a telemetry accumulation, but with a rollover of one million rather than the telemetry rollover value. This is not reset when power failure at the remote causes the telemetry accumulation to reset to 0.

• Complex alarm and event processing on the rate value or on the telemetry pulse input.

• Historical data collection of the current rate by exception and at periodic intervals.

• Current and previous primary and alternate quantities (for example, rate integrations).

• Current and previous primary and alternate average rate.

• Attachment to an Application Calculation Engine (ACE) routine for calculations or control.

From the Controller interface, a rate record can be manually overridden with a value or enabled to use the telemetry/calculated rate value. Also, a rate record’s alarms can be inhibited or enabled and its alarm limits changed. For more information on controlling points and field devices, refer to the AVEVA Enterprise SCADA HMI Controller documentation.