Virtual Flow Computer (VFC) alarm and event summary

Jump

(Non-persistent)

Alarm generated when a VFC accumulator observes a jump in the delta values coming from the associated rate point.

"Virtual flow computer ‘<VFC name>’: accumulator jumped by <jump value> <volume unit> over <jump duration> seconds (<number of bad readings> intervals)."

Spike
(Non-persistent)

Alarm generated when a VFC accumulator observes a spike in the delta values coming from the associated rate point.

"Virtual flow computer ‘<VFC name>’: accumulator spiked by <spike value> <volume unit> over <spike duration> seconds (<number of bad readings> intervals)."

Bad Delta Violation
(Persistent)

Alarm generated when a VFC accumulator observes several bad delta values coming from the associated rate point. The number of bad delta values needs to exceed the configured number of maximum bad delta values allowed in order for this alarm to be generated.

Pulse input and Pulse&Analog rate input:

"Virtual Flow Computer '<VFC Name>': Accumulator '<Accumulator Name>' has violated the number of allowed bad deltas. Please see event log for details."

Analog input rate input:

"Virtual flow computer ‘<VFC name>’: accumulator flowrate <flowrate reading> violated maximum flow rate <maximum flowrate> over <number of bad readings> intervals"

"Virtual flow computer ‘<VFC name>’: accumulator flowrate <flowrate reading> (magnitude <absolute flowrate reading> violated maximum flow rate <maximum flowrate> over <number of bad readings> intervals."

Return-To-Normal

(Non-Persistent)

Alarm generated to clear the Bad Delta Violation persistent alarm.

"Virtual flow computer ‘<VFC name>’: accumulator is back to normal state."

Meter Factor Configuration Alarm

An alarm and event are generated when the virtualflowcomputer record automatically creates a mtrfact record with the default meter factor value (1.0). The mtrfact record is created when an appropriate mtrfact could not be found for use in conjunction with the associated accumulator.

Meter Factor for Rate: <rate name> and Product Group: <product group name> does not exist. Created default meter factor.

Invalid Accumulator Configuration

Event generated when a VFC accumulator is removed from processing due to invalid configuration (Input Rollover less than Maximum Reasonable Flowrate, or less than 1).

Accumulator: <accumulator name> has an invalid configuration and will be not be processed until the misconfiguration is resolved.

Catch Up Event

An event generated when a positive-only VFC accumulator receives a negative volume increment from its associated rate telemetry, indicating that a specific volume has already been accounted for.

No alarm is generated for this event.

Unexpected drop in accumulator positive-only VFC accumulator telemetry of <Volume><Unit Profile>. Accumulator entering catch-up state and ignoring volume increment.

Reset Weighted Average Density (WAD) Event

Event will be generated after the WAD is reset.

Accumulator <Accumulator Name> had a reset detected on weighted average density from <Previous Weighted Average Density> to <Reset Value> by <User> at <System>.

Reset Weighted Average Temperature (WAT) Event

Event will be generated after the WAT is reset.

Accumulator <Accumulator Name> had a reset detected on weighted average temperature from <Previous Weighted Average Density> to <Reset Value> by <User> at <System>.

Reset Weighted Average Pressure (WAP) Event

Event will be generated after the WAP is reset.

Accumulator <Accumulator Name> had a reset detected on weighted average pressure from <Previous Weighted Average Density> to <Reset Value> by <User> at <System>.

Invalid Top of Day configuration

This persistent alarm is generated when an invalid Top of Day is configured for the VFC record (it can be an invalid GroupTOD or an incorrect Top of Day hour).

The alarm will be generated at the next Top of Hour.

Virtual flow computer '<VFC Name>' configuration error. A valid Top of Day should be set or it should have a Group with a valid Group Top Of Day. Until this issue is resolved, Top of Day aggregation will use midnight as default hour.

Invalid Top of Day configuration

(Return-to-normal)

This Return-to-Normal alarm is generated when the invalid Top of Day configuration is resolved.

The alarm is generated as soon as the problem is resolved.

Virtual flow computer ‘<VFC name>’: Top of Day configuration error has been resolved, Top of Day aggregation is using configured hour.

Virtual Flow Computer Periodic Aggregation Reset Event

This event is generated when the periodic aggregation counters are reset manually.

Virtual flow computer '<VFC Name>' hourly, daily, monthly, and yearly periodic aggregation reset. Indicated volumes: <Hourly Indicated Volume>, <Daily Indicated Volume>, <Monthly Indicated Volume>, <Yearly Indicated Volume> <Volume Unit>. Gross standard volumes: <Hourly Gross Standard Volume>, <Daily Gross Standard Volume>, <Monthly Gross Standard Volume>, <Yearly Gross Standard Volume> <Volume Unit>. Masses: <Hourly Mass>, <Daily Mass>, <Monthly Mass>, <Yearly Mass> <Mass Unit>.

Virtual Flow Computer Total Aggregation Reset Event

This event is generated when the total aggregation counters are reset manually.

Virtual flow computer '<VFC Name>' periodic aggregation total reset. Indicated volume: <Indicated Volume Quantity> <Volume Unit>. Gross Standard Volume: <Gross Standard Volume Quantity> <Volume Unit>. Mass: <Mass Quantity> <Mass Unit>.

Accumulator Periodic Aggregation Reset Event

This event is generated when the accumulator periodic counters are reset.

This event happens automatically when the parent VFC periodic aggregation is reset.

Accumulator '<Accumulator Name>' hourly, daily, monthly, and yearly periodic aggregation reset. Indicated volumes: <Hourly Indicated Volume>, <Daily Indicated Volume>, <Monthly Indicated Volume>, <Yearly Indicated Volume> <Volume Unit>. Gross standard volumes: <Hourly Gross Standard Volume>, <Daily Gross Standard Volume>, <Monthly Gross Standard Volume>, <Yearly Gross Standard Volume> <Volume Unit>. Masses: <Hourly Mass>, <Daily Mass>, <Monthly Mass>, <Yearly Mass> <Mass Unit>.

Accumulator Total Aggregation Reset Event

This event is generated when the accumulator total counters are reset.

This event happens automatically when the parent VFC total aggregation is reset.

Accumulator '<Accumulator Name>' periodic aggregation total reset. Indicated volume: <Indicated Volume Quantity> <Volume Unit>. Gross Standard Volume: <Gross Standard Volume Quantity> <Volume Unit>. Mass: <Mass Quantity> <Mass Unit>.

Orifice Meter Failed to Calculate Alarm

This persistent alarm is generated when an accumulator configured as an orifice meter fails to calculate volume, flow rate, or mass values. For the duration of this alarm, the flow rate will be 0 and volume and mass fields will no longer update.

Virtual Flow Computer '<VFC name>': Accumulator '<Accumulator Name>' failed to calculate volumes, flow rates, and mass. Please see error log for details.

Orifice Meter Failed to Calculate Return-To-Normal

This non-persistent alarm is generated to clear the Orifice Meter Failed to Calculate persistent alarm.

Virtual flow computer '<VFC Name>': Accumulator '<Accumulator Name> ' is back to normal state.