Inventory Planning with MRP: Process Details

When inventory planning is performed, the system analyzes particular data based on inventory planning settings and existing open documents that may influence the planning. In this topic, you will find information about how inventory planning works in MYOB Acumatica Manufacturing Edition.

Data Used in Inventory Planning

During inventory planning, the system analyzes the following documents:

  • Demand documents (such as a sales order or forecast), which generate demand for items or cause items to be issued from one of the company's warehouses
  • Supply documents (such as a purchase order or transfer order), which cause receiving items in one of the company's warehouses

The extended list of documents and data used in inventory planning is the following:

  • Forecasts on the Forecast (AM202000) form
  • Sales orders on the Sales Orders (SO301000) form that are not processed to completion, including open transfer orders and blanket sales orders
  • Shipments on the Shipments (SO302000) form with items that have not been issued
  • Inventory on hand and unreleased inventory transactions, which include documents on the following forms:
  • MPS orders on the Master Production Schedule (AM201000) form
  • Production orders that are not processed to completion on the Production Order Details (AM209000) form
  • Purchase orders that are not processed to completion on the Purchase Orders (PO301000) form
  • Two-step transfers between warehouses on the Transfers (IN304000) form, if the Multiple Warehouses feature is enabled on the Enable/Disable Features (CS100000) form
  • Kit assembly orders or kit disassembly orders on the Kit Assembly (IN307000) form, if the Kit Assembly feature is enabled on the Enable/Disable Features form

You manage the set of entities included in planing at the warehouse level. For details, see Inventory Planning Configuration: General Information.

Components Used for Inventory Planning

During inventory planning, the system analyzes which components of items to be produced will be needed and suggests creating purchase orders if it discovers any shortage. The system determines the needed components as follows:

  • For production orders, the material details with a quantity remaining are always used.
  • For planned orders, the most recent active revision of the bill of material whose identifier is specified in the Planning BOM ID box on the Manufacturing tab of the Stock Items (IN202500) is used. If this box is empty, the bill of material specified in the Default BOM ID box on the same tab is used.
  • For master production schedule (MPS) orders, the bill of material specified in the order is used.

Additionally, the system uses the effective start date and effective end date specified for each material line in the bill of material to determine if a component is effective at the time when planned orders are generated.

The system selects the active bill of material based on the effective dates of the BOM revision. For example, if a revision exists for a future start date, it will be used for planned orders with a start date on or after this date.

Order of Creating Planning Orders

During inventory planning, the system analyzes the hierarchy of items based on the bills of material assigned to items and starts creating planning orders from the top-level items. It generates low-level codes for each item and component. The top-level items, such as items to be produced, are assigned the zero code. Then the system analyzes the components of the top-level items and assigns them the 1 code. If any of the components is a subassembly, which also should be produced, the system then analyzes its components and assigns them the 2 code. This procedure is repeated until the lowest level of components is reached.

Dates on Supply and Demand Orders Used in Inventory Planning

The system uses the following dates specified in supply and demand documents during inventory planning:

  • Sales orders and transfer orders: The Ship On date in each document line on the Sales Orders (SO301000) form
  • Purchase orders: The Promised date in each document line on the Purchase Orders (PO301000) form
  • Production orders: The Start Date of each operation on the Production Order Details (AM209000) form
  • MPS orders: The Start Date of each operation on the MPS Listing (AM000004) form

Consolidation of Demand Documents

If the Use Days of Supply to Consolidate Orders check box is selected in the Consolidation section of the Inventory Planning Preferences (AM100000) form, the system consolidates items with the same ID from multiple demand documents into a single planning recommendation during inventory planning. (For more information, see Inventory Planning Configuration: System-Wide Settings.) The system uses the earliest requested date from the demand documents of the group as the action date of the planning recommendation.