In PlanetTogether, Material Requirements Planning (MRP) is an automated process that compares the demand for materials and finished goods to the existing on-hand and planned supply to create jobs and purchase orders to satisfy those demands. In the MPS/MRP Optimize feature, the system will create jobs and/or purchase orders and then schedule them according to the optimization settings defined.
Setting Up MPS/MRP Optimized Settings:
- MPS/MRP Cut-off Duration: Only inventory requirements for a specified duration will be considered to generate jobs and/or purchase orders during the MRP process. Shorter-term MRP Cutoff dates are preferred in situations where demands further in the future do not need to be included in the schedule to improve performance. The cut-off duration options are:
- Short-Term: When this option is selected, the system will only look at the inventory adjustments made within the short-term span defined in the System Options.
- Planning Horizon: When this option is selected, the system will look at the inventory requirements found within the planning horizon defined in the system options.
- No Cutoff: When this option is selected, the system will look at the inventory adjustments of the entire schedule.
- Specific Duration: Selecting this option will prompt the user to select a time span from a drop-down menu that will appear on the right. The user can select a time span from 0 minutes to 2 years in which the system will look at inventory adjustments to create new jobs and/or purchase orders.
Note: When the clock is advanced, the MRP Cutoff Date is extended by an amount of time equal to the clock advance duration to preserve the "horizon." If Personalized Optimize Settings are used, then these are not altered during clock advances.
- Update Sub-Job Need Dates: Sub-jobs are jobs that are created to fulfill material requirements for successor jobs. The need dates for those jobs can be specified using the following options:
- Use System Options: The MPS/MRP tab of the System Options can automatically reset the sub-job need dates based on the parent jobs when the schedule changes.
Note: setting up the sub-job need dates using the system options will override changes made in the MPS/MRP Optimize tab. To use the MPS/MRP Optimize tab options, make sure that you select “Disabled” for the Set Sub-Job Need Dates field of the system options.
- To earlier of JIT and scheduled start date: The need date of the sub-job is set to the earlier of its JIT start date or its parent job’s scheduled start date.
- To JIT date: The need date of the sub-job is set to the JIT start date of its parent job.
- To Start Date: The need date of the sub-job is set to the scheduled start date of its parent job.
- To bottlenecked Operation start date: The need date of the sub-job is set to whichever operation is causing a bottleneck.
- Use JIT Dates
- JIT Compress: The JIT Compress function will shift operations towards their JIT time while preserving their sequence to reduce early production and accommodate high future capacity loads. If this box is checked, the MRP will run JIT Compress after each optimization and cause MRP to generate lower-level supplies based on the JIT schedule of the jobs that consume them.
- Net Change: Only run MPS/MRP on the inventories that have changed since the last run. This reduces the time required for MRP to process and preserve jobs and purchase orders previously created for inventory plans that have not changed since the last MRP run. Inventories for items are excluded from the Net Change MRP run unless one or more of the following have changed for that item or one of its parent items:
- Sales Orders
- Transfer Orders
- On-Hand Inventory
- Safety Stock
- Safety Stock Priority
- Jobs created, deleted, or changed in quantity (producing or consuming the item)
- Consume Forecasts: If selected, running MRP will cause forecasts to be consumed (reduced) before the main MRP logic is executed.
- Generate Jobs to satisfy demand and material requirements: When checked, MRP will create sub-jobs to create materials to supply demands.
- Preserve these Jobs during Generation: There are benefits to preserving some stability in production and purchase plans in most situations. For example, once jobs are released to the shop floor, it can be problematic to have them be deleted by MRP and replaced with new jobs. In addition, once a purchase order has been placed to a vendor, it may not be possible to change or cancel it. Therefore, the jobs checked will not be deleted by MRP when generating new jobs to satisfy demand and material requirements:
- Released: Jobs that are released will be preserved if this box is checked.
- Planned: Jobs that are planned will be preserved if this box is checked. Conversely, unchecking this box can allow Firm jobs to be scheduled before planned or estimated jobs.
- Firm: Firm jobs will be preserved if this box is checked.
- Estimate: Jobs that are estimated will be preserved if this box is checked. Unchecking this box allows Firm jobs to be scheduled before estimated or planned jobs.
- Starting in the Plant Stable: Preserve jobs that have any activity scheduled to start within the Plant Stable Span.
- Previously Generated Jobs: Jobs that MRP previously generated are preserved.
- Anchored: Preserve job if any activities are anchored to a scheduled time.
- Locked: Preserve job if any activities are locked to a resource.
- Printed: Preserve jobs that have been printed.
- CTP Jobs: Preserve if the job was created from a CTP (Capable To Promise).
Note: The following are always preserved:
- Jobs that are started
- Jobs that have DoNotDelete=true
- When running a Net Change MRP, jobs that produce inventories are not included in the Net Change MRP process.
- Purchase to Stocks that are either Firm or Closed.
- Generate Purchase Orders to satisfy demand and material requirements: When checked, MRP will create purchase orders to buy materials as needed based on the item and inventory planning fields.