Slotting in SAP Extended Warehouse Management (SAP EWM) is the process of putting goods in a warehouse in a way that ensures the most appropriate storage and picking of goods. Slotting uses a variety of data to determine suitable optimal putaway control parameters. These parameters describe the storage section in which the product is to be stored, the properties that the storage bin is to have, and the putaway strategy that is to be used. These parameters are listed below:
- Product master
- Storage requirement data
- Packaging data
- Demand forecast data
Slotting helps in determining the most optimal putaway parameters that ensure placement of goods in suitable bins in the warehouse. It determines suitable putaway parameters such as storage type, storage section, and bin type for placement of goods.
Configuration Steps for Slotting
To use slotting in SAP EWM, you first need to configure related objects. This process requires you to complete seven steps as shown in Figure 1.
Configuration steps in SAP Extended Warehouse Management (EWM)
Step 1. Create a Condition Table
Condition tables are used for different applications, for example, packaging specification determination, printing warehouse orders, and slotting. In this article I explain how to create a condition table for slotting.
In a condition table you specify the combination of fields that should form the individual condition record. The number of fields used for a condition table is limited to 10. In the example discussed in this article, I have selected two fields, Warehouse Number and Warehouse Product Group, to form condition records. These fields are used later in the article for Condition Record Maintenance.
To create a new condition table in SAP EWM execute transaction code SPRO and follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Condition Table > Edit Condition Table for Putaway Control Indicator.
In the screen that appears, enter the name of the Condition Table (ZCON_TAB) and a Description (Condition Table for Putaway Control). Select the CONLG_NUM and CON_MATGNR fields from the list of available fields and move them to the right by clicking the arrow button highlighted in yellow as shown in Figure 2.
The main screen of the condition table
(Note: The condition table can contain as many fields as needed. For my example, select fields for Warehouse Number and Warehouse Product Group.)
In the same screen, you can see both the fields are now available on the right side (Figure 3). Save and activate the table by clicking the activate icon and then clicking the save icon.
Activate the condition table
After activation, at the bottom of the same screen you can see that green logs are generated and the status of table changes to Active as shown in Figure 4.
Condition table activated
Step 2. Create an Access Sequence
An access sequence is used to specify the sequence in which the system processes the condition tables when searching for specific condition records. This setting is made specific to the condition type using an access sequence. Each condition table contains a specific combination of fields that the system should look for in the condition records. In the above step, the condition table contains two fields, Warehouse Number and Warehouse Product Group. When the slotting process is executed, the access sequence is used to read the linked condition table (ZCON_TAB). The match is successful if the condition table fields match the input parameters.
To create a new access sequence in SAP EWM execute transaction code SPRO and follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Access Sequence > Edit Access Sequence for Putaway Control Indicator.
In the next screen (not shown), click the New Entries button, which takes you to Figure 5. Enter the name of the Access Sequence (ZAS) and a Description (Access Sequence). Click the Accesses folder.
The access sequence header
In the same screen, enter 1 in the Access field. The value in the Access field is a sequence number. If you define more than one condition table you could enter it as sequence 2. In my example, you define only one condition table, so enter 1 here. Enter the name of the table created in step 1 (ZCON_TAB) and then select the E check box. Click the save icon to save your entries as shown in Figure 6.
Access sequence details
(Note: The E indicator stands for exclusive indicator. That means that the system does not search for a further record after the first access from a record to a condition type in an access sequence has been successful.)
Step 3. Create a Condition Type
A condition type is used to specify the attributes, field combinations, and business meaning of condition records. For example, it can be used to create various condition types for packaging specification determination in warehouse order creation.
To create a new access condition type in SAP EWM execute transaction code SPRO and follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Condition Type > Edit Condition Types for Putaway Control Indicator.
In the screen that appears, click the New Entries button, which takes you to Figure 7. Enter the name of the condition type (e.g., ZPC#) and the Access Seq. (access sequence) that you created in step 2 (ZAS). Other details are proposed by default and are not changed. Click the save icon to save your data.
Condition type details
Step 4. Create the Slotting Procedure
A slotting procedure is used to define which condition types are to be considered and in which order. The system automatically determines which procedure is valid for a business transaction and takes into account the condition types contained within it, one after another.
To create a new slotting procedure in SAP EWM execute transaction code SPRO and follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Determination Procedure > Edit Determination Procedure for Putaway Control Indicator. In the screen the system displays, click the New Entries button, which takes you to Figure 8.
The slotting procedure header
Enter the name of the Procedure as ZSP and the Short text as Slotting procedure. Click the Elements of Determination Procedure folder.
In the field under the LvNo (level number column) enter the 1. In the field under the Ctr (counter) column, enter 1, and in the field under the Condition Type column, enter ZPC# (Figure 9). You created the ZPC# condition type in step 3. Click the save icon. The level and counter denote the sequence for the determination procedure. For example, there can be several counters within one level.
Slotting procedure details
Step 5. Assign the Slotting Procedure to a Warehouse Number
Before assigning the slotting procedure created in step 4 to a warehouse number, you need to create a warehouse. To create a new warehouse number, execute transaction SPRO and follow menu path Extended Warehouse Management > Master Data > Define Warehouse Number. In the screen the system displays, click the New Entries button, which takes you to Figure 10.
Warehouse created and saved
Enter the number of the warehouse (ZEW2) in the Warehouse No. field and a Description (Enterprise Warehouse 2). Click the save icon.
Now to assign the slotting procedure to the new warehouse you just created, follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Determination Procedure > Assign Determination Procedure. In the new screen, click the New Entries button, which takes you to Figure 11.
Assignment step complete
Enter the usage as PU (Warehouse Parameter Determination), the warehouse number ZEW2 you created, and the slotting procedure as ZSP, which was created in step 4. Click the save icon.
Step 6. Create a Condition Maintenance Group
A condition maintenance group is used to bundle condition tables and types for condition maintenance together. To create a new condition maintenance group in SAP EWM execute transaction code SPRO and follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Settings for User Interface > Create Condition Maintenance Group. In the screen that appears, click the New Entries button, which takes you to Figure 12.
The condition maintenance header
Enter the name of the maintenance group (Z_SLOT) and a description (Slot Condition). Click the Condition Maintenance Group: Detail folder. This action displays the screen shown in Figure 13.
Condition maintenance details
In Figure 13, enter the Counter (1), Usages (PU), Condition Table (ZCON_TAB), Condition Type (ZPC#), and Description (Condition Maint. Group). Click the save icon to save your data.
After you click the save icon, the system generates the logs showing that all the configuration steps are successfully completed, as shown in Figure 14. Click the enter icon (the green checkmark).
Condition maintenance success logs
Step 7. Assign the Condition Maintenance Group to the Maintenance Context
After defining the condition maintenance group, you need to specify condition maintenance groups for a context. Context defines the situation or circumstance under which the condition maintenance group is used. For my example, assign a general condition maintenance (GCM) context to the condition maintenance group (Z_SLOT).
(Note: SAP provides other contexts, such as TAX_ENGINE, that are used under business scenarios related to finance. For basic condition records and condition maintenance group, the context GCM is used.)
To register the condition maintenance group in SAP EWM, execute transaction code SPRO and follow menu path Extended Warehouse Management > Good Receipt Process > Slotting > Condition Technique > Settings for User Interface > Register Condition Maintenance Group.
In the screen that appears, enter the maintenance context GCM and click the enter icon as shown in Figure 15.
The maintenance context header
In the next screen (not shown), click the New Entries button to go to Figure 16. Enter the name of the Group (Z_SLOT) and a Description (Slot Condition). Click the save icon to save your entries.
Condition maintenance context details
Condition Record Maintenance
After the configuration shown in the above section is complete, you need to maintain the condition records. Condition records are where specific values for the condition table are maintained. In step 1 in the “Configuration Steps for Slotting” section, the condition table contained two fields, Warehouse Product Number and Warehouse Product Group. You need to maintain the values for these two condition records. The condition record is the place in which you maintain the values for materials or services to calculate in the business process or whose values are involved in the data process of the business. Execute transaction code /SCWM/GCMC to display the screen shown in Figure 17. Enter the name of the maintenance group (Z_SLOT) and then click the execute icon. This action displays the screen shown in Figure 18.
The condition record entry screen
In Figure 18, enter the condition type (ZPC#) and then press the Enter key.
The condition record header
After you press Enter, additional columns are populated as shown in Figure 19.
Condition record with additional columns
Fill in the details for other columns as shown in Figure 20 and then click the check icon highlighted in yellow. For my example, enter values in the fields under the WhN (warehouse number) column (ZEW2) and WhsProdGroup (warehouse product group) column (001, ZBIG, and 002). Note these two fields are the condition records that you maintained in the condition table (ZCON_TAB) in the screen shown in Figure 3.
Condition record data entry check
For my example, you also populate the fields under the PACI (putaway control indicator) column for three warehouse product groups as 0010, 0050, and P150. Note that the Status column displays red symbols for the rows in which you have entered data as the system has not yet checked these values. After clicking the check icon (highlighted in yellow), this status changes to green.
In the refreshed screen (Figure 21), all rows are now active and are showing as green. So basically, the rows in Figure 21 indicate that if the warehouse product group is 0001, the system should get the PACI as 0010, if it is ZBIG, it should be 0050, and if it is 0002 then it should be P150. (In Figure 21, PACtrInd stands for putaway control indicator. In other screens in the SAP system, the abbreviation PACI is used for putaway control indicator.)
Active condition records
Master Data Update
In the above section, I defined three warehouse product groups (0001, ZBIG, and 0002) to be used during assignment of the PACI. These three warehouse product groups have three different PACIs defined, so when the slotting process is executed, each PACI is assigned to the correct warehouse product group. Now I assign these three warehouse product groups to three product masters. This helps in ensuring that when the slotting process is executed, the system should determine the suitable PACI to get the correct bin proposal.
Note that in Figure 21, you created three rows and all three warehouse product groups are assigned to the same warehouse (ZEW2). Under warehouse ZEW2, you define three warehouse products, and each of these three warehouse product has one warehouse product group assigned to it. Therefore, when slotting is executed, the system assigns the PACI assigned to each warehouse product group as per the settings in Figure 21 to the corresponding warehouse product to which these warehouse product groups are assigned.
To maintain the warehouse product, execute transaction /SCWM/MAT1. In the screen that appears (Figure 22), enter the product number (T-EW10), the Warehouse No. (ZEW2), and Party Entitled to Dispose (ZEWM). Click the Change button.
The warehouse product header
This action displays the screen shown in Figure 23. Under the Storage Tab, enter the Warehouse Product Group (0001) and then click the save icon. For my example, you have assigned Product Group 0001 to product T-EW10.
Assign Warehouse Product Group 001 to product T-EW10
Follow similar steps to assign the Warehouse Product Group 0002 to product T-EW11 and Warehouse product Group ZBIG to product T-EW12 as shown in Figures 24 and 25, respectively.
Assign Warehouse Product Group 002 to product T-EW11
Assign Warehouse Product Group ZBIG to product T-EW12
Slotting Execution and Results Interpretation
Next, I show you how to run the slotting process. To execute slotting, execute transaction /SCWM/SLOT. In the screen the system displays, click the right arrow (highlighted in Figure 26) to enter all the product names.
The initial Slotting screen
In the Select Single Values tab of the pop-up screen (Figure 27), enter the name of the assigned products (e.g., T-EW10, T-EW11, and T-EW12).
Product entry for slotting
Click the execute icon to display the Slotting screen (Figure 28).
In the Slotting screen, enter the warehouse number (ZEW2) and click the execute icon to display the screen shown in Figure 29. Figure 29 lists all three products and the corresponding warehouse numbers. Select all three rows and then click the execute icon to perform the slotting process.
Products and warehouse numbers listed
At the bottom of the same screen (Figure 30), logs are generated for all three rows.
Slotting results logs
Click any of the rows to display the corresponding log details (Figure 31).
Slotting logs details
In Figure 31, the screen lists logs with green blocks, indicating that slotting was successful.
Note that this is just simulation of the slotting process. To update the results, click the Mode button on top of the screen as shown in Figure 32.
In the pop-up screen (Figure 33) select the radio button option Status Grn/Yellw. Selecting Status Grn/Yellw instructs the system to select and process all rows that have an exception status color of green or yellow. Click the OK button.
Slotting results rows selection
After you click the OK button in Figure 33, the system displays the screen shown in Figure 34. Note that in the fields under the Status column, the save icon appears in each of the three product rows of the product. Click the save icon at the top of the screen and then close the screen.
Slotting results saved
After executing the slotting process, you can view the results by executing transaction code /SCWM/MAT1. In the screen the system displays (Figure 35), enter data in the Product Number (T-EW10), Warehouse No. (ZEW2), and the Party Entitled to Dispose (ZEWM) fields. Click the Display button.
The warehouse product master initial screen for product T-EW10
In the next screen, under the Whse Data tab, you can see that Planned Putaway Ctrl Ind. has been updated to 0010. This is because product T-EW10 had the Warehouse Product Group assigned as 0001 and the sequence was maintained in the condition record. If the Warehouse Product Group is 0001, the system should get the PACI as 0010, which is what is present in Figure 36.
Planned PACI updated for product T-EW10
Similarly, the PACI is updated as P150 for product T-EW11 and 0050 for product T-EW12 as shown in Figures 37 and 38, respectively.
Planned PACI updated for product T-EW11
Planned PACI updated for product T-EW12
Note that in Figures 36 to 38, the PACI is updated in the Planned Putaway Ctrl Ind. field in the product master. This is because slotting was not yet activated for any of the product masters. To activate the slotting, execute transaction /SCWM/SLOT and select any one of the rows. For example, select the third row and click the activate icon as shown in Figure 39.
Slotting activated for one product
This action displays the screen shown in Figure 40.
Slotting is active
In Figure 40, you can see that the activate icon is present against the third row, meaning that slotting is active for product T-EW12.
To see the results of this activation, execute transaction /SCWM/MAT1. In the screen the system displays (Figure 41), populate the Product Number (T-EW12), Warehouse No. (ZEW2), and the Party Entitled to Dispose (ZEWM) fields.
The warehouse product master initial screen for product T-EW12
Click the Display button to display the screen shown in Figure 42.
PACI updated for the product master
Select the Whse Data tab in the screen shown in Figure 42. Note that the Putaway Control Ind. field has been updated to 0050.
Common Issues in Use of Slotting in SAP EWM and Resolution
Slotting is one of the key concepts in SAP EWM for optimal storage bin determination. Here is a list of frequent issues encountered during its configuration and use:
- Deletion of product storage types. Sometimes when slotting is used for mass processing of products, the storage types of the product are deleted, which is incorrect behavior. For example, slotting is executed collectively for two product master PROD-A and PROD-B – and activation of slotting is done initially for product PROD-A followed by PROD-B. In the Product Master, the storage type of the first product (PROD-A) may be deleted.
Reason and solution. The reason for this is a bug in standard program behavior. Global variables are not refreshed, which results in this erratic behavior. To correct this activate Business Add-In (BAdI) /SCWM/EX_SLOT_UPD_STORGE_TY.
- Values in the product master are erased on slotting activation. When slotting is run via transaction /SCWM/SLOT and activation is done via transaction /SCWM/SLOTACT, the values in the product master are erased. This error occurs when system logging for slotting is enabled.
Reason and solution. The reason for this is that the slotting log and the slotting user selection parameters were not considered during activation. To correct this, you need to modify the standard ABAP object /SCWM/CL_CONCEPTING_CORE ACTIVATE_MATERIAL. SAP has also provided a solution for this issue via SAP Note 1545916.
- Performance issues in the slotting run. When slotting is executed for a large number of products via transaction /SCWM/SLOT, the system takes a lot of time to execute and update the results.
Reason and solution. SAP has provided multiple improvements in the system in general and for slotting in particular. Ensure that SAP EWM is upgraded to the latest enhancement pack and also that SAP Note 1459635 is implemented in the system.
Another point to remember when using slotting in SAP EWM is that when you use transaction code /SCWM/MON, the Warehouse Management Monitor is a good central place to give a high-level overview of the warehouse situation (Figure 43). It also contains alert monitoring capabilities. It helps in resolving many consistency check issues. For example, before starting SAP ERP Central Component (SAP ECC) and SAP EWM processing, you can use this transaction to check the stock of the material in the required batch and storage bin.
The Warehouse Management Monitor