The external system is to perform all warehouse functions and assume responsibility for warehouse management and warehouse control for a specific warehouse.

Scenarios 3, 4 and 5 must be considered in conjunction with an automatic warehouse. This section describes the fourth scenario. You should consider all three scenarios if, in a concrete situation, a decision regarding the use of the WM system in an automatic warehouse is to be made.

In a warehouse complex with many different warehouses (these are different storage types from the point of view of SAP), different storage techniques can be used in the individual warehouses. A warehouse with several manual storage types and one or more automatic storage types would be possible. The automatic storage type is highly automated and very complex with regard to its structure and the storage technique used. Management of this storage type is linked directly to warehouse control, that is, in order to define a goods movement, information on the current status of the warehouse systems is required. A large number of individual communication processes between the WM system and external system would have to be expected in this case. This communication is also very time-critical, i.e. certain events in the warehouse control unit would require an immediate response from the warehouse management system. The asynchronous interface, which is currently used for communication between the WM system and external system, is thus not suitable for such a dynamic warehouse. A system which can handle all aspects of warehouse management and control in one software package would be far more effective for managing this storage type.

Since the automatic storage type only represents part of the warehouse complex and most of the warehouses are managed manually, the WM system can be used for the entire warehouse complex. The WM system manages the entire warehouse complex and distributes the individual stock placement and removal procedures amongst the individual storage types. In manual warehouses, all aspects of warehouse management are controlled by the WM system. The automatic warehouse is regarded as a ‘black box’ by the WM system, i.e. the WM system does not recognize any storage bin stock in the warehouse.

In this scenario, the following functions are performed by the WM system for the automatic warehouse:

• Management of summarized stock for each material

• Initiation and generation of goods movements

• Determining the storage bins for the individual movements

• Generating goods movements within the storage type

• Inventory taking

• Controlling the conveyors

• Controlling the material flow

• Optimizing resources

The automatic warehouse is defined in the WM system as a specific storage type. There are several different ways in which the storage type can be managed by the WM system:

1. The storage type is defined with a fixed storage bin (similar to an interim storage area) and all stock is managed in this storage bin
2. Several storage bins are defined in the storage type which do not, however, correspond to the physical storage bins. Additions to existing stock must be possible in the warehouse with the result that a storage bin is always occupied with one material. The stock for one specific material thus accumulates in one storage bin; a new material is always assigned to a new storage bin. This type of management can be used if you encounter problems blocking the storage bins with option 1.

The storage bin in the WM system has no significance for the external system.

A possible method for distributing the functions between the WM system and the external system for this warehouse is described in the following examples:

WM:

• Communicates with other SAP components such as SD, MM and PP

• Initiates goods movements

• Generates transfer orders

• Sends generated transfer orders to the external system; the material identification, quantity and cause of the movement, but not the storage bin, are of significance

External system: :

• Determines storage bins for stock placement and stock removal

• Optimizes the material flow

• Executes the individual goods movements

• (Reports the goods movements to the WM system

• Executes inventory

• Reports differences to the WM system

• Initiates and executes movements such as stock transfers within the warehouse

WM:

• (Reports confirmed transfer orders)

• Generates transfer orders for the reported differences

The WM system handles communication with the other SAP components for the entire warehouse complex and thus also for the automatic warehouse. When goods are received, the MM system informs the WM system of the pending stock placement. The WM system generates a transfer order with one or more items for the goods receipt. The destination of the stock placement is determined, i.e. the storage type in which the goods are to be placed into stock. If the automatic warehouse is selected for the stock placement, the transfer order items concerned are transferred to the external system with the standard IDoc WMTOID01. The stock placement procedure is then processed further by the external system. The goods to be placed into stock are identified in the external system either by means of the transfer order number and items that have been sent or the storage unit number. It is not essential for this goods movement to be reported to the WM system.

When stock is removed or picked, the scope of the procedure is determined in the WM system and one or several transfer orders are generated. A picking procedure can involve several different storage types in this case as well. All of the transfer order items which are relevant for the automatic warehouse are prepared in the WM system and transferred to the external system with the standard IDoc WMTOID01. The storage bin from which the goods are optimally removed from stock or picked is selected in the external system. If picking is carried out in the external system, the picking procedure should also be reported to the WM system. The data for this must be structured in the same way as the standard IDoc WMTCID01 on the external system side and sent to the SAP system so that the individual transfer order items with the actual quantities can be confirmed in the SAP system.

Any differences that are established in the external system, either by means of an inventory or online, must be reported to the WM system. The standard IDoc WMTOID01 must be generated in the external system for individual material differences and sent to the WM system. A transfer order is generated from the IDoc in the WM system in order to post the difference from the warehouse in an interim record for differences.

The movements within the warehouse do not need to be sent to the WM system as only the summarized stock is managed in here.