Exchange rate adjustment do same for both AX or NAV or even you look into some high end ERP.
It basically adjusts the transactions for change in exchange rate. Unrealized and realized entry are posted for gain and loss.
In AX, You have exchange rate adjustment in GL, AP and AR module.
The difference is GL adjusts exchange rate for all customer vendor and GL transactions while exchange rate adjustment in AP and AR adjusts exchange rate for respective module only.
I request you to please explain bit more about the above sentence.
Assume i have posted a Purchase invoice transaction on 01/07/12 with USD currency - exchange rate 3.75 Where we need to enter the new exchange rate ( 4.15) against the same date (01/07/2012) for adjustment?
Then what is the use of the exchage rate adjustment batch job in the AP ?
( In NAV , Currency form we have two fields like Exchange rate and Adjustment exchange rate . With out reversing the invoice we can update rate in the field of adjustment exchage rate in the currency form , and when we run the currency exchange rate batch job system would consider that value in the field of adjustment rate , post the adjustment entries to customer ledger entry and G/L entry )
The theoretical value (book value) of open vendor transactions in foreign currencies varies over time with fluctuations in exchange rates.
To update the value of your accounts payable, and to conform to the U.S. generally accepted accounting principles (GAAP), you run the exchange adjustment periodic job. By using a new exchange rate, the job revalues the amounts that were open (not settled) on a specified date. The differences between the original posted amounts and the revalued amounts are posted in the ledger and to vendor accounts as unrealized exchange adjustment transactions. Transactions that have been exchange adjusted on a more recent date are not revalued.
Before you run an exchange adjustment for a specific date, you can get an idea of the financial impact of the adjustment by running the exchange adjustment simulation.
Consider the following scenario in Microsoft Dynamics AX 2009 or in Microsoft Dynamics AX 2009 with Service Pack 1 (SP1).
You post an invoice for a foreing customer in a date that uses an exchange.
You settle the invoice in a later date that uses a different exchange rate.
You change the exchange rate for the posting date of the invoice.
You run the exchange rate adjustment by using the posting date of the invoice as the Considered date and the Date of rate.
In this scenario, the exchange adjustment process does not recognize any adjustments, even though there is a difference after you changed the exchange rate on the posting date. The exchange adjustment process does not include transactions that were settled past the Considered date and the Date of rate.
Exchange rate adjustment routine in AR and AP only considers open transactions. As you have settled your invoice that is why you are not seeing effect of exchange rate adjustment event after changing the rate.