G/L Account Determination 
Use this window to define default G/L accounts for transactions created in SAP Business One.
Each of the window's four tabs contains the definitions for G/L accounts related to a specific area of the business activity: Sales, Purchase, General, and Inventory.
To open this window, choose 
Administration 
Setup Financials G/L Account Determination 
.
Recommendation
For more information, go to the Education tab of the SAP Business One Customer Portal and take the following training: Financials Prepare for Financials Start Using Financials
View the Default Accounts for Automatic Posting (G/L Account Determination) .
End of the recommendation.