When you apply entries in different currencies to one another, there may be a small rounding difference. In this case, you can have the program completely close the entries and post these small rounding differences. To do so, you must specify the interval that you will accept as a rounding difference for the relevant currencies.
Open the Currencies window.
In the Currencies window, in the Appln. Rounding Precision field, specify the interval that you will accept as a rounding difference for the relevant currency.
When you apply entries in different currencies to one another and the payment entry is in LCY, you can also specify an interval that you will accept as a rounding difference for LCY. You do this in the Appln. Rounding Precision field in the General Ledger Setup window.
Allowing for Application of Vendor Ledger Entries in Different Currencies
Setting Up the G/L Account for Rounding Differences