Understanding Tank Dip Readings

Use the Tank Dip Readings program to record the physical stock (dip) levels in the tanks. The system uses the dip readings to calculate tank volume, which is necessary to process operational reconciliations.

After you record the readings, the system checks these factors to calculate volume:

• Gross dip reading against the tank height and the tank reference height.

• Water dip reading against the gross dip height.

• Dip temperature against the minimum and maximum temperatures set for the tank.

• Density temperature against the minimum and maximum temperatures set for the tank.

For Liquefied Petroleum Gas (LPG) products, the system uses the vapor pressure and temperature to calculate the liquid equivalent of the vapor portion of the product. It then adds this liquid amount to the liquid volume which it calculates from the dip reading to calculate the total volume of product in the LPG tank.

The system retrieves existing tank levels from the Bulk Product Transaction File table (F41511). You can change this information and enter dip readings to record the current stock levels. You cannot change the tank levels that appear after the reconciliation process has begun.

If no previous readings exist for a particular tank, the system updates the tank status to inactive.

You can record transactions for the tank before an initial dip reading. If the initial reading is not before the transaction dates, the system treats the transactions as retroactive (that is, before the last reconciliation) and does not include them in the reconciliation.