MRP execution parameters
There are several parameters below in the initial screen of MRP execution transactions like MD01, here, I am summrizing their usages and also introduce how they work with their corresponding customizations.
- Scope of planning.
- Processing key
- Create purchase requisition
- Create MRP list
- Planning mode
- Planning date
- Parallel processing
- Display Material list
- User exit key
- User exit parameter
1. Scope of planning:
It can group multiple plants and MRP areas, so those can be run together by one time execution.
Customization transaction code: OM0E
2. Processing Key:
NEUPL: Regenerative planning, all materials whose MRP type is not ND are planned.
Technically speaking, the materials who have planning file entries in transaction MD21.
NETCH: All materials whose MRP relevant objects have been changed and that actions changed the stock requirement situation are planned.
Technically speaking, the materials who have the indicator NETCH get set in the planning file entry are planned, this is for improving the MRP
NETPL: Only materials which had MRP-relevant change in the planning horizon since the last planning are planned and requirements in the planning horizon
Planning Horizon of NETPL:
For plant: Customization transaction, OPPQ > Planning Horizon
For MRP group: Customization transaction, OPPR > Planning Horizon
3. Create Purchase requisition:
- Purchase requisitions
- Purchase requisitions in opening period
- Planned order
Opening period: MRP creates planned orders first internally, if the planned orders whose opening date is earlier than today or the same, then they are converted to purchase requisitions.
The scheduling margin key is entered in the material master, and the opening period can be defined in the customization below for the schedule margin key.
This can be maintained in several places below and they have priorities for total planning (MD01/MDBT or MS01/MSBT or MD40/MDBS) .
1 MRP group (Other execution parameters can also be maintained here.)
3 Initial screen
4. Planning Mode:
1 Adapt planning data (Normal mode) – Only process the changeddata
2 Re-explode BOM and Routing – Read the BOM and routing again for the existing proposals
3 Delete and recreate planning data – Completely delete the MRP data and create again
planning mode 3 is not suggested for better performance unless it is really necessary, mode 1 and 2 is generally sufficient in business.
6. Planning Date:
This is only valid for time-phased planning. In time-phased planning, we can run materials on specific date only, e.g. every Tuesday, the next date to be run is recorded in the planning file entry of that material in transaction MD21. Therefore, the material is planned when its date of planning file entry is the same as the planned date entered in the initial screen of MRP execution transaction.
7. Parallel Processing:
To improve the performance, the materials can be divided into several groups and run on multiple dialog work processes in parallel. The maximum number of work processes and destination instances can be defined in the customization transaction OMIQ. Please make sure that the instance exists in the transaction SM59 and is configured correctly.
If an MRP job is scheduled in parallel on background by transaction SM37, the work processes occupied can be monitored in transaction SM66 below when the job is running.
The program RMMRP000 which is running on background work process (Type BTC) is the main program of MRP, this only divides and distributes the materials to several dialog work processes (Type DIA and programs start with SAPLM61*), RMMRP000 doesn’t run materials actually. It shows the status ‘Stopped’ (Sometimes ‘On hold’) but it doesn’t mean that the MRP job is stopped or is held because the materials are running on other dialog processes and it is just waiting for the result from them so shows those kinds of statuses. Thus, if you’d like to make a trace for performance analysis, the dialog work processes should be traced instead of the main program RMMRP000.
8. User exit Key, User exit Parameter:
User exit M61X0001 can be implemented to exclude some materials from planning, the user exit key and parameters can be entered, those are transferred to the user exit to identify what materials should be excluded. E.g. the parameter can be the MRP controller or MRP group or material group etc.
The user exit contains 2 function modules below. The 2 function modules should be programmed with the same source codes if the user exit is active because one is for non-parallel processing and another one is for parallel processing.
The user exit key and parameter are the importing parameters of the function modules as showed in the screen shot below, so they can be transferred to the function modules, and can be excluded by writing own source code there based on the parameters transferred.