MFG/PRO 9.0 User Guide Volume 3: Manufacturing - QAD.com

Component Effective Dates
MATERIAL REQUIREMENTS PLANNING 249
MRP uses component effective dates to determine which components are
required for a given order due date. Components are active beginning on
the start date specified in the product structure and remain active through
the stop date, the last day a component will be used.
Executing MRP
MRP Processing
MRP reports and inquiries can optionally display item requirements
summarized by week. The beginning day of the week is specified in the
Summary Default field of the MRP Control File. Calculations are based
on this weekly period.
MRP calculates net requirements for items using three variables:
• Gross item requirements are the sum of an item’s requirements from
forecasts, higher level products, customer orders, service items, and
intersite orders. They do not take into account inventory on hand or
scheduled receipts.
• Scheduled receipts for that item, including open purchase orders,
open work orders with a quantity open and a status of R, and intersite
requests for DRP items.
• Quantity on hand from the previous period.
MRP uses these three variables in the following calculation:
Net Requirements = Gross Requirements – Quantity on Hand for the
previous period – Scheduled Receipts
MRP schedules planned purchase orders and work orders to fill these net
requirements. Planned work orders generated by MRP are exploded into
gross requirements for their components. This process continues until
there are no more planned work orders to explode.
Note MRP does not explode product structures for purchased and
distribution items or components with structure code Document.
Ï See “Engineering
Effectivity” on
page 23 for more
information on
how MRP
handles
component
effective dates.