RF in SAP Warehouse Management, a White Paper By Shashank Shekhar, Deloitte Consulting LLP
Significance of RF in Warehouse Management:
Mobile data entry in the warehouse involves the use of wireless radio frequency (RF) terminals or devices carried by the warehouse staff to record data. The use of bar codes and RF devices has made warehouse operations more efficient. Data entry errors are fewer and the time needed to perform operations in the warehouse has been reduced because the date can be collected by a RF device without requiring manual collection and manual entry of data. The use of RF devices for data collection and transaction processing in warehouse management has been increasing over a number of SAP releases. The modern efficient warehouse uses RF technology and constantly reviews procedures to further adopt the technology to improve operations.
Technical and Functional Landscape of RF environment
Efficient warehouse management processes requires faster data entry and processing for inbound, outbound and internal warehouse operations. SAP transactions can be executed on RF devices that are handheld (terminals, barcode scanners) or forklift mounted. No middleware software is required to connect the devices to SAP.
SAP’s functionality enables real time handling of material flow through RF scanning devices. There are two standard RF devices that can be used with SAP which are
- 1. GUI Devices: uses windows based operating system and this graphical user interface RF device can use a small keypad, touch screen or some other procedure, but the data is always displayed to the user in a graphical manner. The device is connected to the SAP system as any other standalone computer.
- 2. Character based devices: The character based device is not connected directly to SAP but communicates via an interface called SAP Console. The communication between SAP console and the RF device can be achieved using a Telnet server. Two industry standard screen sizes are supported by SAP
A. RF Devices for Forklift: 8 X 40 (8 lines by 40 characters)
B. Portable RF Devices: 16X20 (16 lines by 20 characters)
RF screen for 8X 40 looks like
SAP Console enables RF devices to be run within SAP applications. SAP Console is used as a framework for automatic data collection in a warehouse environment. SAP console translates GUI screens to character based screens that are used on a variety of data collection devices. The SAP console does not contain business logic, database or external functionality. Its sole function is to translate SAP GUI screens in the SAP environment to the character based equivalent. The SAP console consists of four components, which are:
1. RF terminal: The RF terminal which is the Telnet Client receives data directly from the SAP System and transmits the results back to the system. We can scan the information that needs to be recorded, such as storage unit numbers, using a bar code (for example, based on UCC/EAN128 standards), and also use the bar code scan to verify the storage bins.
2. RF Access Point which allows for wireless Ethernet
3. Telnet Server/SAP Console Administrator, which allows each RF terminal to convert to the window machine in character, based mode and supports VT220 terminal emulation.
4. SAP R/3 system that receives the data from mobile terminals
1. RF in distribution environment
Radio Frequency is primarily used in Warehouse Management process in distribution environment as it efficiently handles the huge volumes of transactional data processing requirements and minimizes human interventions. The high volume of warehouse transaction processing requirements in industries like Retail, chemicals, pharmaceuticals, Auto Components can be handled using the RF integration with warehouse Management. The following processes can utilize radio frequency devices:
1. Goods Receipt Processes with shipping notifications
2. Goods Issue Processes for outbound Deliveries
3. Internal Warehouse Processes
4. Stock Transfer Processes within the Distribution Network
5. Physical Inventory Processes for the warehouses within the Distribution Network
2. RF Supported Warehouse Processes: The following Warehouse Management Processes are supported by RF
A. Goods Receipt Processes with RF:
RF supports Goods Receipt Processes with Inbound Delivery. The goods receipt for the inbound delivery can be performed based on the Inbound Delivery number, Handling Unit Number, Staging Area, Shipment Number etc. warehouse workers can perform the following goods receipt-related functions:
- Check all delivery items and report differences
- View and change shipment information
- Print shipping unit labels
- Unload deliveries
- Pack/unpack delivery items
- Generate and confirm TOs for delivery items
- Post goods receipts to Inventory Management
B. Goods Issue Processes:
The goods issue processes are based on the outbound delivery and can be performed for the outbound deliveries identified by Delivery Number, Handling Unit (HU) Number, Staging Area, Shipment Number, Group Number etc.
Using the RF devices, Warehouse Workers can perform the goods issue related activities like view and change shipment related information, print shipping unit labels, pack/unpack delivery items, load deliveries, split deliveries, generate and confirm transfer orders for delivery items, post goods issue to inventory management
C. Put away Processing:
Radio Frequency supports the put away processes and it is based on the Transfer Orders created in warehouse management. Put away can be performed based on the selected storage unit/handling unit, selected by deliveries, selected by transfer orders or cluster
D. Picking Process for Deliveries: Picking execution is based on transfer orders created in the warehouse management as part of the delivery processing processes.
E. Physical Inventory:
RF devices can be used for inventory counting, enabling a greater degree of accuracy and efficiency. New Dynamic Cycle Counting functionality provides a number of features that facilitate cycle count in the warehouse including Physical Inventory counting against inactive inventory documents (while open transfer orders exist for a bin), inventory counting at quant level, creation of inventory documents by RF users and automatic clearing of active and inactive documents.
3. Associated SAP Configuration for RF
a. Configuration for Bar codes: Verification profile is a set of fields that can be verified by the user.
Path: IMG>Logistics Execution>Mobile Data Entry> Verification control> Define Profiles
b. Verification profile can be assigned to movement types used in warehouses that will be subject to bar code scanning.
Path: IMG>Logistics Execution>Mobile Data Entry> Verification control> Assign Verification Profiles to Goods Movements.
c. Define bar codes for warehouse
Path: IMG>Logistics Execution>Mobile Data Entry>Bar Code> Assign Bar Code Types to Warehouses.
d. Maintaining Bar code specifications
Path: IMG>Logistics Execution>Mobile Data Entry>Bar Code> Maintain Bar Code Specification.
e. Defining the Radio Frequency Queue: To assign a range of activities to certain users, functionality called the RF Queue Management must be defined
Path: IMG>Logistics Execution>Mobile Data Entry>Rf Queue Management > RF Queue Definition
Path: IMG>Logistics Execution>Mobile Data Entry>RF Queue Management > RF Queue > Assign areas and activities to queue
Path: IMG>Logistics Execution>Mobile Data Entry>RF Queue Management > RF Queue > Assign processors to queue
4. Reasoning for Developing Custom RF transactions
The following developments take place in warehouse management with RF
1. Making Changes in Standard SAP Transaction using user exits
2. Making Custom Development
In the first case like other SAP modules, changes can be made in the standard SAP transactions to meet the specific business requirements using the suitable user exits. In general the custom RF transactions are developed to merge several RF transactions into one RF transaction in order to optimize and reduce the process steps to be carried out. For example for a goods receipt of an inbound delivery with handling units the GR transfer order should be created, it should be confirmed and put away transfer order should be created for the same. Therefore the GR process includes execution of three standard SAP RF transactions but the same processes can be executed using single custom developed RF transaction.
The custom RF Transaction development includes the following steps:
1. Creation of the executable program
2. Creation of the screen
3. Creation of the function module to access the screen
4. Screen Programming
5. Subroutines to call the screen and check the data coming from the screen
6. Assigning transaction code to the program
7. Assigning transaction code to the RF menu
The custom development should be made considering the workload and the extent to which the automation is required in the warehouse. The average transaction volume, warehouse efficiency and the cost/benefit analysis should be made before deciding on the custom development requirement.
5. Day in the Life flow using RF Technology
Warehouse Management transaction LRF1 is used to monitor the queues of warehouse person. Warehouse supervisors can drag and drop the transfer orders from one queue to other as per the load situation, user absence. The transfer order priorities can also be changed as per the requirement. The monitoring of the queue can be configured per warehouse based on the business requirements by following the given steps:
– Define Queue
– Assign areas and activities to the queue
– Assign processors (users) to the queue
The limitation imposed by the transaction LRF1 restricts more than one user to access the transaction per warehouse. The transaction LRF1 can also be used in conjunction with the SAP Delivery Monitor transaction VL06 for warehouse workload estimating.
6. Change Management Related topics for WM and RF
The following change management related topics should be considered before implementing WM and RF
1. Selection of appropriate RF Device based on the existing business processes
2. Transaction Volume analysis and assessment of custom developments
3. Identifying users and setting up appropriate users profile and assigning users to the RF monitoring queue
4. Users training and Process Documentation