This is what the help file is saying, hope it helps:
Purchased goods that you pay through a procurement card are received immediately if they are purchased from the store, or later if you order them through E-Procurement. For each purchase, you can enter a purchase requisition or you can import a purchase requisition file from E-Procurement or another application.
The procurement card company sends procurement card statements periodically. The procurement card statement contains the product code, the credit card number, and other details, which are also registered for the purchase requisition. The procurement card statement must be matched against the purchase requisitions and then approved for payment. For purchase payment authorization, you must process procurement card payments in the same way as cost invoices. If you did not enter a purchase requisition earlier, you can still enter the purchase requisitions or you can manually approve the procurement card statement.
A ledger posting is made when you enter the purchase requisition and when the procurement card statement is invoiced. All the purchase requisitions for which no procurement card statements are received for payment can be accrued to a special ledger account. This enables you to control the entire procurement cycle, from a purchase requisition to payment and reconciliation with the general ledger.
Desktop Receiving means that SSA ERP posts expected purchase invoice accrual for the entered purchase requisitions. If you select the Desktop Receiving check box for a purchase requisition in the Purchase Requisitions (tfacp2528m000) session, SSA ERP creates a posting on the Invoices to be Received (GRNI) account when you save the purchase requisition. At period end, the accrued amount of purchase requisitions that are not yet matched to procurement card statements is transferred to the next period.
For procurement card statements with desktop receiving, SSA ERP calculates price differences. You must approve price differences that exceed the defined tolerances. For details, refer to Authorization of price differences and additional costs
If you clear the Desktop Receiving check box, no postings are made when you enter purchase requisitions. At the end of a period, you can use the Post Accrual Journal Entries (tfacp2260m000) session to accrue the purchase requisitions for which you not yet received procurement card statements for payment. After performing the accrual posting, SSA ERP handles the purchase requisition in the same way as a purchase requisition to which you apply Desktop Receiving.
The procurement card company generates a matching line for each procurement card statement line. The matching line contains a combination of matching fields such as the requisition date, the supplier, and the item. For each procurement card company, you can define the format of the matching line used on the procurement card statement lines. The format is based either on separators between the data fields or on the fixed lengths of the data fields.
To define matching lines, use the following sessions:
Matching Criteria (tfacp0112m000).
Matching Fields By Matching Criteria (tfacp0509m000).
If you enter the procurement card definition in the Procurement Cards (tfacp0508m000) session, you must also enter the procurement card company and select the matching code format used by the procurement card company. If you enter a purchase requisition in the Purchase Requisitions (tfacp2528m000) session, you must specify the procurement card that was used to pay for the goods. SSA ERP then builds a matching line for the purchase requisition from the data that you enter and in the format that you linked to the procurement card.
If you import procurement card statements and/or purchase requisitions as an XML file, the file includes the matching lines. It is recommended that you manually check the matching lines and correct them if necessary, before you match the procurement card statements to the purchase requisitions.
Past adjustment lines represent still open amounts of previous procurement card statements that were not paid or that were partly paid. If you enter a procurement card line of the Past Adjustments category, SSA ERP closes the previous procurement card statement. The open amount is paid through the past adjustment line of the current statement.
Excess billing occurs if the quantity of goods invoiced through the procurement card statement exceeds the quantity specified on the purchase requisition. In the Purchase Requisitions (tfacp2528m000) session, you can select how you want to process the excess billing. In all cases, the requisition is set to Posted.