Account determinations are separated via processing keys that the system uses for different transactions.

OB40 - Define Tax Accounts

• Double click on the Process key (the first screen is the rules).  Once you set the rules, it cannot be changed unless all the account determinations are first erased.  For certain rules, the indicator that are greyed out as it cannot be maintained.
• Click the Accounts button for the Accounts Assignment Screen.
• Click the Posting keys for assign the Posting keys (Debit/Credit).
At the Posting keys screen, the note "Posting keys are independent of chart of accounts" means that if it includes more than one chart of accounts, the debit/credit posting keys set here will be valid for all the charts of accounts.