How to avoid suggestions (WOS/POS) while resources (WOF/POF) cover the requirements (SOF)?

1 minute read time.

In Enterprise planning workbench,  MRP will keep suggesting a new purchase order (PO) and cancel the existing PO. It fails to give an 'advance' suggestion, or suggestion to increase the quantity on the existing PO, which is expected behavior based upon experience with other MRP systems. For companies with simple products MRP can be managed by working through the details manually, but in a complex environment with large multi-level BOMs and many components, the requirements are going in every direction and it's almost impossible to get to the bottom of the suggestions.

Let's take a look at one scenario and how to fix it.

- GESITF: Manufactured item’s production LT = 30 days

- Reorder policy setup

- ADPVAL: General parameter LATSUGDAT in STO/REA is set to “First possible date + Lead time”.

- GESPCB: Requirements parameters setup with 30 days backward and forward LT for WOF.

- GESSOH: Generate a SO for QTY of 5 and the requirement date “04/18/19”.

- FUNMRP: Run MRP

- FUNDBENCH: Convert the WOS into a WOF.

- FUNMRP: Run MRP


- FUNDBENCH: MRP suggests to cancel the WOF and delay the WOS instead of suggesting to advance

Solution:

- To avoid suggestions while resources cover the requirement, increase the replanning horizon in order to include the production lead time of the products.

- This setup permits to have a good MRP message and to not have a new suggestion (WOS).

  •               We are running 6.5 and we are having trouble with replanning rules.   As a simple example we have a firm WO, an SO, and 2 PO’s.   We move the SO date out farther, and we get a suggestion by MRP to move the WO date out, but the raw materials that the WO needs as reflected in the PO’s we are not getting any messages to move them out no matter what we do with the replanning parameters.  Of course we would like to see the message to move them out so that we don’t purchase ahead of when we need the materials.   Our rules are set up for simulation.  Is there something else we need to do to make sure that the replanning explodes down to the materials?