Firm and Planned Requirements
On supplier schedules, item requirements can be either firm or planned. Requirements designated as firm are:
• Not replanned when Schedule Update from MRP is run
• Visible to MRP as scheduled supply, like discrete purchase orders
Requirements designated as planned are not considered sources of supply by MRP and may change when MRP is rerun. The schedules you send to suppliers can contain firm requirements only, planned requirements only, or a combination of both.
The schedule update process automatically applies a status of firm to item requirements that are:
• Within the number of firm days (firm interval) specified on the associated scheduled order line
• Within the schedule days specified on the scheduled order line
Schedule Update from MRP only designates shipping schedule requirements as firm. It does not designate item requirements on planning schedules as firm, even when planning schedule active dates are within the schedule firm interval. However, you can manually designate detail line quantities as firm on individual planning schedules, if required.
Any unreceived firm requirements from one release are automatically carried forward to the next release during schedule update. These quantities are maintained as a prior cumulative requirement.
Planned orders outside the firm days period are approved, but maintained as planned requirements. This means that they are not seen by MRP as sources of supply and can be replanned. When you rerun MRP, it plans or replans orders for scheduled requirements that are now within its planning horizon. Executing Schedule Update from MRP adds the new and updated planned orders, designating as firm any requirements that now fall within the Firm Days period.
If requirements change, you may need to manually adjust firm quantities in Supplier Shipping Schedule Maint (5.5.7.7) or Supplier Planning Schedule Maint (5.5.7.6).
• When increased demands create additional requirements within the Firm Days period, MRP creates planned orders in that period. When you regenerate the schedule, the system does not select any planned orders falling within the firm period covered by a schedule. The warning message Order not selected displays in the report.
• When requirements decrease due to decreased demands, MRP sees the supply as excessive and produces action messages.
You can avoid rescheduling problems due to fluctuations in short-term MRP data by setting Firm Days to zero on scheduled order lines. When Firm Days is zero:
• Firm requirements are not generated or carried forward from one release to the next.
• The system sets Prior Cum Req equal to Prior Cum Received.
• Each schedule release is based on the most recent MRP planned-order data available.
Use a positive number in the field if you have an agreement with this supplier that requirements will not change within a specified time period.
Important: To avoid schedule discrepancies between printed bucketed schedules and the actual required schedule, firm days should never exceed the number of days specified in the Schedule Days field.