36 Generate Material Requirements Plans

This chapter contains the topic:

Section 36.1, "Generating Material Requirements Plans."

36.1 Generating Material Requirements Plans

Navigation

From Material Planning Operations (G34), choose Single Site Planning

From Single Site Periodic Planning Operations (G3422), choose MRP Regeneration

Use MRP Regeneration to produce a single facility MRP planning schedule for the items that you select. Alternatively, you can use MRP Net Change to produce a single facility MRP planning schedule. You can generate a material requirements plan for:

A single item
All items
Only items that are affected by transactions since the last generation

When you generate a material requirements plan, the system evaluates selected information, performs calculations, and recommends a time-phased replenishment plan for all selected items.

MRP regeneration uses the same programs as DRP/MPS regeneration. The following summarizes these programs:

Function	Description
MRP Regeneration	MRP Regeneration is a batch program that produces an MRP schedule for all items that are selected in the data selection criteria. When you run MRP Regeneration, the system: Reads the selected forecast Uses data from the MRP inclusion rules to calculate requirements for master planned items Generates a time series and messages for the selected items and components of selected items
MRP Net Change	MRP Net Change is the same batch program as MRP Regeneration. The data selection is further defined to include only the items that you selected on Net Change Review. When you run MRP Net Change, the system: Evaluates selected information Performs calculations Generates a time series and messages for the selected items and components of selected items

36.1.1 Before You Begin

Verify that MRP/CRP has been set up.
Understand the concepts and terms described in Single Level Master Scheduling. See Section 15, "Overview to Single Level Master Scheduling."
Generate a forecast for independent demand items. See Creating Detail Forecasts in the JD Edwards World Forecasting Guide.

36.1.2 What You Should Know About

Topic	Description
Bill of material	MRP uses the bill of material to explode demand to all component items. If a parts list does not exist for a work order, MRP generation uses the standard bill of material to explode demand. You should define a bill of material type M (standard manufacturing bill) for work order headers without a parts lists and for parent planned orders. The MRP generation uses bill type M to sequence items according to how the product is built.
Low level code	The system uses the low level code to determine when to generate a time series for an item. MRP generation explodes lower level demand only for manufactured items. The system does not explode demand to levels below a purchased item, even if that item has a bill of material.
Generation type	You must use generation types 4 and 5 to generate a master planning schedule for MRP items. If the status of MPS is frozen, generation type 5 explodes only the component items of the master scheduled item. Select generation type 4 to explode MPS items and component items.
Frozen orders	If you identify work orders or purchase orders for an item as frozen, the program does not replan any orders for the item. Instead, you receive a frozen order message for that item.
Data selection	To run MRP regeneration, base your selection on branch/plant, category codes, and planning code. The system can process any selection from based-on table fields. To run a net change generation, set the net change flag to 1 to select items that have changed since the last generation of the program.