Skip to Content

Archived discussions are read-only. Learn more about SAP Q&A

Lot of Lot Size Calculation

Dear Experts,

I am having this the following scenario which I would like to ask if someone has come across on.

We are using EX (Lot for Lot Order Quantity) with the Minimum Lot Size and Maximum Lot Size set as 0.

Original data in MD04 Rec./reqd Qty Available Qty


Stock 0

Production Order (PrdOrd) 459 459

Order Reservation (OrdRes) 459- 0

Production Order (PrdOrd) 53 53

Order Reservation (OrdRes) 53- 0

Production Order (PrdOrd) 105 105

Order Reservation (OrdRes) 105- 0

Everything is fine as the every order requirement has been fulfilled with a Production Order. These Production Orders has been converted from Previous Planned Order

The Production Planning Department then inserts a Production Order at the top of the chain. Which is as follows

Updated data in MD04 Rec./reqd Qty Available Qty


Stock 0

Order Reservation (OrdRes) 1000 1000-

Production Order (PrdOrd) 459 541-

Order Reservation (OrdRes) 459- 1000-

Production Order (PrdOrd) 53 947-

Order Reservation (OrdRes) 53- 1000-

Production Order (PrdOrd) 105 895-

Order Reservation (OrdRes) 105- 1000-

Now we run MD01 again to generate the MRP Requirements and the following is the output generated

MD04 Data after MRP Run Rec./reqd Qty Available Qty


Stock 0

Plan Order (PldOrd) 383 383

Order Reservation (OrdRes) 1000 617-

Production Order (PrdOrd) 459 158-

Plan Order (PldOrd) 459 301

Order Reservation (OrdRes) 459- 158-

Production Order (PrdOrd) 53 105-

Plan Order (PldOrd) 53 52-

Order Reservation (OrdRes) 53- 105-


The SAP system creates a Plan Order at the top of the list. But I would like to ask why the Quantity is 383 instead of 1000 which fulfills the Production Order of quantity 1000 which is newly inserted.


Former Member
Former Member replied


Yes, Rescheduling horizon is where you decide how the rescheduling function will work. This is turn has an impact on the dates and quantities of new planned orders. Rescheduling can be set at the plant level, or at the MRP group level.

This functionality supports the way most companies actually work. Rather than create a brand new planned order within a very short time horizon, they will instead expedite existing production orders. It is a business decision. One does not normally change these settings without first discussing the matter with the manufacturing and purchasing people.

For more info, review online help

and all of the F4 help entries within the rescheduling sections of OPPQ/OPPR.

Best Regards,


0 View this answer in context
Not what you were looking for? View more on this topic or Ask a question