Metering and Virtual Flow Computer (VFC) terminology

Accumulator

A measuring device that collects information from virtual flow computers.

Active Ticket

The ticket that is tracking the volume currently passing through the Batch Transfer location.

Alarm Reset

To reset all period alarms, select Alarm Reset.

Alarm States

The alarm state of the detect record. Possible alarm states include:

Normal — Batch Tracking detected the interface at the calculated threshold value and within the configured volume.

Threshold — The densities of two consecutive batches are too close together; Batch Tracking is unable to calculate an appropriate threshold value.

You may be able to correct this condition by entering a smaller deadband value in the Analog Deadband field on the Interface Detect Control dialog. Alternatively, you can disable interface detection for the following batch.

Volume — Batch Tracking detected the interface outside of the configured volume deadband.

Ambient Temperature

The temperature of the surrounding atmosphere.

Audit

This field indicates whether or not any field in the ticket was edited.

Auto Switch

This field indicates whether or not the automatic switching function is activated. If this feature is enabled, the Metering application automatically starts the next ticket in the pending queue when the volume to go on the active ticket reaches zero.

Batch

A specified (batch) amount of product shipped by a customer.

Batch ID

Identifier for a batch.

By default, Batch IDs must adhere to the following standards:

• They must begin with a letter.

• They must be no more than 31 characters in length.

• The only special characters permitted in the Batch ID are the hyphen (-) and the underscore (_).

  If the Batch ID fails to meet these standards, an error message will appear. The standards for Batch IDs can be configured by the Administrator and may be different on your system.

  An Administrator may prohibit duplicate Batch IDs.

Clear Resettable Values

Select Clear Resettable Values to reset the indicated and gross standard resettable counters.

The counters are reset to zero, and the application resumes counting. However, when the resettable counters reach the value displayed in the Rollover field, they are reset automatically.

Completed Ticket

Completed tickets are queued for your verification before they are stored in the Historical database. This applies both to normal tickets and to remote tickets.

Contaminated

This field indicates whether or not the ticket was flagged as contaminated. Indicates a mixing of products that may make sample impure or unsuitable.

Creep Alarm

If the positive creep limit is set, the system will generate an alarm if the tank is declared idle and the tank level increases from the saved level by more than this amount.

If the negative creep limit is set, the system will generate an alarm if the tank is declared idle and the tank level decreases from the saved level by more than this amount.

CSW

Correction factor for the presence of sediment/water in crude oil. This level is never greater than 1.0000.

Current GSV

Current volume corrected to standard temperature and pressure.

Cut Type

Indicates the point in the interface between two batches at which the system declares the detected interface.

• Mid — The detected interface is declared at the midpoint of the interface between the current batch and the next batch

• Head — The detected interface is declared at the beginning of the interface between the current batch and the next batch.

• Tail — The detected interface is declared at the end of the interface between the current batch and the next batch.

Density (weighted average)

The volume weighted average density.

Down Counter

Counts down from the value of the Target volume (original).

Duration

The time in minutes to maintain the meter at the desired flow rate.

When you enter a time, the simulation will proceed using the specified flow rate. When the time has elapsed, simulation ends.

Ending

The ending accumulator reading.

• Ending (accumulator reading) — current accumulator count.

• Ending (pending ticket) — The time at which the ticket is scheduled to end.

End Time

Actual time the ticket was cut.

Est End Time

The estimated time at which the application will pump the scheduled volume of the ticket.

Est Stop Time

Estimated Stop Time.

ETA Target

The estimated date and time at which the target volume will be reached. (The estimate is based on the flow rate shown in the Flow Rate field and the volume shown in the Target Volume field.) This target is non-editable.

Flow Rate

Amount of liquid flowing for a specified amount of time.

Group

The group to which a Batch Transfer or a VFC belongs.

GS Flow Rate

The current flow rate corrected to standard temperature and pressure.

GS Flow Rate (meter simulation)

The desired simulated flow rate.

GSV

Gross Standard Volume (corrected to standard temperature and pressure).

GV

Gross Volume (the indicated volume with Meter Correction Factor (MCF) applied but without corrections for temperature, pressure, and density).

GSVolume to Go

The GSV remaining in the active ticket.

Indicated Volume

The raw, uncorrected volume.

Inhibit

Stop AVEVA Enterprise SCADA from generating an alarm / logs.

Inhibit Alarm

• Inhibit Alarm (target volume) — To Inhibit the alarm when the meter reaches its target volume.

• Inhibit Alarm (volume) — To inhibit the alarm when the volume remaining before the target volume is less than the warning volume.

• Inhibit Alarm (warning time 1) — To inhibit the alarm when the estimated time remaining before the target volume will be reached is less than warning time.

• Inhibit Alarm (warning time 2) — To inhibit the alarm when the estimated time remaining before the target volume will be reached is less than warning time 2.

Inhibit Log

• Inhibit Log (target volume) — To inhibit logging an event when the meter reaches its target volume.

• Inhibit Log (volume) — To inhibit logging an event when the volume remaining before the target volume is less than the warning volume.

• Inhibit Log (warning time 1) — To inhibit logging an event when the estimated time remaining before the target volume will be reached is less than warning time 1.

• Inhibit Log (warning time 2) — To inhibit logging an event when the estimated time remaining before the target volume will be reached is less than warning time 2.

Inhibit Record

Inhibits the currently selected record.

Level

Current level in a tank. The level is converted to a gross volume using a volume conversion table (strapping table).

Maint. To Normal

Manually stopping a ticket sends the active ticket to the unverified queue and identifies the next ticket from the pending queue as a maintenance ticket. Maint. to Norm. will change the ticket’s status from maintenance to normal.

Maintenance Ticket

When a ticket is stopped manually, the system sends the current ticket to the unverified queue and identifies the next ticket as a maintenance ticket and is designed to record any accidental volume flow not assigned to a regular ticket. Any subsequent movement of a commodity through the Batch Transfer is added to this ticket.

MCF

Meter Correction Factor.

Meter Correction Factor

A factor used with a meter to correct for ambient conditions. The factor for a fluid-flow meter to compensate for such conditions as liquid temperature change and pressure shrinkage.

Meter ID

The configured meter ID of this accumulator. Typically, the name of the rate point.

MTR Config

The current configuration of the meter:

Receipt — A receipt meter (also called a lifting meter) introduces liquid into the pipeline.

Delivery — A delivery meter removes liquid from the pipeline.

Enroute — Liquid simply flows through an enroute meter; there is no change in the amount of commodity in the pipeline.

Node

Name of the node at which the detector is located.

NSV

The Net Standard Volume (the same as GSV, but with sediment and water volume removed).

Obs Density

The observed raw density reported from the field. Depending on the field device, it may be fully or partially corrected.

Obs Pressure

The raw pressure reported from the field.

Obs Temp

The raw temperature reported from the field.

Percent Complete

Indicates the percentage amount of target volume accumulated on the ticket (non-editable).

Pipeline

The name of the pipeline associated with a Batch Transfer.

PMC Name

The Physical Meter configuration name.

Press Factor

The Pressure Correction Factor for the meter.

Product Group

The name of the product group for which this meter correction factor is valid.

Pumpable Volume

The volume of space remaining in the tank. The current standard/indicated volume in the tank is subtracted from the configured maximum safe tank volume to calculate the volume to fill. If the volume in the tank is greater than the maximum safe volume, the volume to fill is negative.

Rate of Change Alarming > Enabled

When Rate of Change Alarming > Enabled is selected, an non-persistent alarm may be generated when the Rate of Change (ROC) of the tank volume exceeds specified limits.

Rate of Change Inhibit

Inhibit will suppress AVEVA Enterprise SCADA from generating a non-persistent alarm when the ROC of the tank volume exceeds the specified limits.

Filling ROC Limit (Units/Hr)

The filling ROC limit. If the flow rate exceeds this limit, the tank will then be in an ROC Alarm state.

Emptying ROC Limit (Units/Hr)

The emptying ROC limit. If the flow rate exceeds this limit, the tank will then be in an ROC Alarm state.

Remaining Volume

The volume of space remaining in the tank. The current standard/indicated volume in the tank is subtracted from the configured maximum safe tank volume to calculate the volume to fill. If the volume in the tank is greater than the maximum safe volume, the volume to fill is negative.

Reset

To clear all editable fields.

Reset Accumulation Counters

The resettable counter is reset only on your command or when it reaches the software rollover value. This will reset the counter to zero.

Reset Periodic Integration Counters

This will reset the hourly, daily, weekly, monthly, and yearly counts to zero.

Resettable Counter Information

Resettable counters can be reset at your discretion.

Revised

This field indicates whether or not the ticket is a revised ticket (a revised ticket cancels out a previous ticket).

Rollover

When the resettable counters reach this value, the application automatically resets the counters to zero.

Scheduled

The scheduled GSV of the active ticket.

Shipper

The pipeline account associated with the ticket.

Shipper ID

The shipper ID for which this meter correction factor is valid.

Split Ticket

Splitting a ticket divides it into two consecutive tickets and is primarily designed to allow a cutoff for month-end accounting.

Strap Type

This field displays the level units used for the strapping table. The strapping table maps total volume to a specific level or increment and is used to convert a tank level reading into a volume.

Switch on Volume

When Switch on Volume is enabled, the Metering application will automatically start the next ticket in the pending queue when the volume to go on the active ticket reaches zero.

Switch Status Pt

If a status point changes in a batching meter, the Metering application starts a new ticket.

Target Eng Units

The target units in which volumes are displayed. This is non-editable.

Target volume

This field allows you to enter the volume you wish to track. As the volume approaches the target volume, AVEVA Enterprise SCADA generates the warning alarms configured in the following fields:

• Warning Time: 1)

• Warning Time: 2)

• Warning Volume

Target Vol Type

This selection allows you to specify whether the volume being tracked is a gross or net volume.

Gross = Uncorrected volume (Ivolume).

Net = Corrected for temperature and pressure (GSvolume).

Task

Name of the pipeline task.

Throughput Limit

This limit is the maximum amount of commodity that can flow through the meter before the MCF will be considered invalid. A zero (0) indicates that there is no throughput verification for the MCF.

Ticket

Meter tickets record volume information about deliveries or injections. There are three kinds of meter tickets:

1. Pending Tickets record information about planned volume transactions.

2. The Active Ticket records volume information about the commodity currently flowing through a Batch Transfer.

3. Completed Tickets record completed volume transactions.

Ticket ID

Identifier of a ticket.

Ticket Status

The operational status of the active ticket.

Ticket Type

The type of ticket (Maintenance or Normal).

Time Limit

The maximum length of time (in days) that this MCF can be used before it is considered invalid. A zero (0) indicates that there is no time limit for this MCF.

Toggle Contam.

Contaminated tickets are typically tickets in which different product types are mixed. The "contaminated" flag will remain set throughout the ticket (that is, until the next ticket is started, either manually or automatically.

Total Flow Rate

The sum of the GS flow rates for all accumulators.

Total GS Flow

The current Gross Standard flow rate: indicated flow rate corrected to standard temperature and pressure.

Total GV

The Total Gross Volume.

Total GSV

The Gross Standard Volume: indicated volume corrected to standard temperature and pressure.

Total Ind.

The uncorrected, raw flow rate.

Units

The units of the ticketed volume.

Up Counter

As volume accumulates on the new ticket, this field counts up to the value in the Target Vol field. This is non-editable.

Update MCF

Select Update MCF to apply the most current Meter Correction Factors (MCFs) to all meters.

Verify

To verify a completed ticket.

Vol. to Go

The amount of scheduled volume left to pump on the current ticket.

Volume

The Gross Observed Volume (GOV) of product in the tank. The GOV is calculated by converting the tank level via a volume conversion table (strapping table).

Volume Type

Use to select whether the volume being tracked is a gross volume or a net volume.

WAD

The volume-Weighted Average Density.

WAP

The volume-Weighted Average Pressure.

WAMCF

The volume-Weighted Average Meter Correction Factor.

Warning Time

This field allows you to enter a warning time in minutes. When the estimated time remaining before the target volume will be reached is less than this warning time, AVEVA Enterprise SCADA generates an alarm. It is possible to enter Warning Times 1 and 2.

Warning Volume

Enter the first warning time. When the estimated time remaining before the target volume is reached is less than this warning time, RealTime generates an alarm.

WAT

The volume-Weighted Average Temperature.

WAOD

The volume-Weighted Average Observed Density.

WACTL

The volume-Weighted Average Temperature Correction Factor.

WACPL

The volume-Weighted Average Pressure Correction Factor.

Mass

The aggregated mass for the Virtual Flow Computer (VFC).