Update tank counters

Tank management uses both periodic counters and continuous counters. Both the Gross Observed Volume (GOV) and the Gross Standard Volume (GSV) changes are counted. The counters for GOV and GSV are as follows:

• hour

• day

• week

• month

• year

The periodic counters are reset when the end of the period occurs. The continuous and periodic counters are reset by the Controller.

The counter calculation depends on the type of flow configured for update:

• If flow in is configured, an update is only made when the tank volume is higher than it was for the previous calculation:

  

• If flow out is configured, an update is only made when the tank volume is lower than it was for the previous calculation:

  

• If a sum of both flows is configured, the absolute value of any level movement is added.

  

• No counter updates are made when the tank is in an Idle state.

On an hourly basis, AVEVA Enterprise SCADA writes the counters for the above time periods into the Historical database.

The counters are kept in the internal fields in the tank.countersGOV and tank.countersGSV integration blocks (for Indicated Volumes [IVs] and Gross Standard Volumes [GSVs], respectively). The resettable counter is reset only on Controller command, or when it reaches the software rollover value. When the hourly, daily, weekly, and monthly rollover occurs (as per the configured TOD), the counter information is sent to the Historical database. When the product in the tank changes, the counters are sent to the tankCounter table in the Historical database and zeroed.