In a production environment it may not be preferable that new requirements on the short term can influence production quantities. The length of the term can be determined by the planning time fence. How MRP treats new requirements in this period can be determined using the firming type in customizing for MRP type:

The firming type determines how the MRP run treats requirements in relation to the planning time fence. The time fence is counted by number of workdays from today. This number can be set in the material master (MRP1 tab) or in customizing per MRP group.

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