Use the settings in this group to configure the settings for a Meter. The Tank Volume application makes it possible to convert flow from a meter into accumulated volume. It's possible to enable creating transactions automatically, by monitoring changes in the meter's flow rate, or manually, via a control parameter.
Meter Transactions - Configuration Parameters
Enable Meter
Select this option to enable the Meter. When a meter is disabled all data will be cleared and no registers will be read, although status registers will still be written.
This is the register that holds the flow from the meter as a floating point value. The next register will also be read. The flow should always be positive. Values of flow of less than 0 will be clipped to 0.
Use this setting to configure the units for the flow meter. All accumulated volume will be in the same units as the flow rate. For example, if the flow rate is in m3/hr, the volume will be in m3. If the flow rate is in gallon/hr the accumulated volume will be in gallons. If the flow rate is in m3/day, the accumulated volume will be in m3.
Use settings in this group to configure the Tank Volume application to automatically determine when a meter transaction has started or stopped.
Use the Enable Flow Transactions setting to allow a transaction to be started automatically when flow rate increases above the value of Start Transaction Flow. When this setting is not selected transactions will not be started automatically.
Use the Start Transaction Flow value to configure when to start a transaction. When the instantaneous flow rate is greater than the value of the Start Transaction Flow parameter, a new transaction will be started.
Use the Stop Transaction Flow value to configure when a transaction is complete. When the flow rate is less than the than the value of Stop Transaction Flow the transaction will be complete, but only after the Transaction Complete Time has expired. If the flow rate rises above the Stop Transaction Flow value before the Transaction Complete Time expires, the transaction will continue to accumulate volume until the flow rate falls below the Stop Transaction Flow value again.
Manual transactions are always enabled for meters, as long as the Enable Meter option is selected. Use the meter's associated Stop Start Trans control parameter to start or stop a transaction manually.
A transaction that is started automatically can be stopped manually. A transaction that is started manually can be started automatically, but only if the Enable Flow Transactions setting is enabled.
The Tank Volume application tracks the total daily accumulated volume through the meter. The daily accumulated volume can be found in the Volume Tday status parameter. Use the Contract Hour setting to choose the hour at which this values rolls over daily. To roll over at midnight, select 0 for the Contract Hour.
When the Enable Flow Transactions parameter is selected, and meter transactions are started and stopped automatically, the Transaction Complete Time must expire after the flow rate falls below the Stop Transaction Flow value before the transaction is completed.
This setting has no effect on transactions that are stopped manually.
Use these settings to configure what happens when a transaction is complete. Select the En Transaction Register option to allow the application to set the Transaction Register when a transaction is complete. This can be used to trigger user logic or to trigger the Datalogs application to log a set of registers.
This register will not be cleared by the Tank Volume application. It must be cleared in user logic. The Datalogs application will clear the register if the register is used to trigger logging.
The status values in the Last Trans registers will be stable when the coil is set. If logging is desired, log the Last Trans values.
