SAP What is # 1 - What is "Last lot exact" ?

You can find the "Last Lot exact" parameter within the Lot size key in the Customizing.
Use IMG path -> MM -> CBP -> Planning -> Lot-Size Calculation -> Define Lot-Sizing Procedure to navigate to the Lot size parameter in SAP.

In the configuration of the Lot size key "EX", I have "SET" the Last Lot exact field. (I am just fine tuning the Standard Lot Size key of "EX" with Last Lot Exact for demonstrating this concept). You should copy the "EX" lot size to a self-defined Lot-Size Key that begins with "X", "Y", or "Z"; eg: X1 if you need it.

From SAP的学习和考试 Learning & Examination

Assume the following Material Master MRP setup using the Lot size key "EX" (with the Last lot exact parameter) and a rounding rule of 200. (see below).

From SAP的学习和考试 Learning & Examination

Notice that the first two planned order in the Stocks Requirement List is rounded to 200 (according to the Rouding value). However, the LAST LOT is at 50.

From SAP的学习和考试 Learning & Examination

CONCLUSION: The "Last Lot Exact" feature results in the last lot in the MRP calculation with ZERO Available Qty.

APPLICATION: Especially useful in End-Model Calculation where there is an agreement with the supplier to supply the exact quantity when model ends.

CAUTION: Does not apply to all Lot-Sizing Procedures.
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