Field help (POHCCE1) 

During the entry of an order line, the analytical dimension types are initialized according to the POP Default dimensions code.

If the order line originates from a document line, the analytical dimension types are loaded by the analytical dimensions on the source document line. If analytical dimension types are not specified on the source document, an attempt to initialize these analytical dimension types is made according to the Default dimensions code.
When an analytical dimension is used for project management tracking, any modification of the project code on the document line leads to the dimension code being reset based on the Default dimensions setup.
According to the setup of the transaction, the analytical dimensions can be modified.The different analytical dimensions entered in the order line will be transferred to the receipt or to the purchase invoice control. STOP