The prerequisite for a successful MRP planning run are correct low-level codes. You have to execute low-level code determination for products, for example:
If the low-level codes of the products in SAP APO have not been previously determined
If bills of material have changed
If planning packages have been created manually or automatically
To determine low-level codes for products, you execute a heuristic for determining low-level codes for these products in the production planning run. The standard heuristic SAP_PP_020 is available in the standard system for this purpose. This heuristic can do the following for products:
Adopt the low-level codes transferred from SAP R/3 to SAP APO
The low-level codes are transferred during the initial master data transfer from SAP R/3 to SAP APO. Later changes in SAP R/3 are not updated in SAP APO. In such a case, you can calculate the low level code in APO via the heuristic.
Perform a cross-location or location-internal determination of the low-level codes based on the supply chain model
In the cross-location calculation of low-level codes, the heuristic takes account of stock transfers, that is, transportation lanes between locations. You can perform cross-location planning in the MRP planning run based on the low-level codes calculated for all locations.
You can display the low-level code of a location product in the planning file. For more information, see the system documentation for the heuristic SAP_PP_020.
Note
To call the system documentation for a heuristic, in Customizing for
Production Planning and Detailed Scheduling
(PP/DS), under
Maintain Heuristics
, select the
Information
icon for the heuristic.
If the product selection for the heuristic contains a product that belongs to a planning package , the heuristic automatically performs a low-level code determination for all products in the planning package. The algorithm first determines the individual low-level code of each product in the planning package. It then sets the low-level codes of the products to the highest low-level code value that occurs in the planning package. This is relevant for planning with product interchangeability, for example.