Apr 16, 20235 min read

Radio Frequency in SAP ERP Warehouse Management System

Updated: Apr 22, 2023

Radio Frequency in Warehouse Management

Mobile data entry in the warehouse management involves the use of wireless radio frequency (RF) terminals or devices by warehouse persons to record data.
Warehouse efficiency increased by use of barcodes and RF devices.
Data entry errors will minimize. The uses of RF device for data collection and processing warehouse transactions are increasing day by day.
The modern efficient warehouses using RF technologies and constantly adopting the new technologies to improve warehouse operations.

Technical and Functional Landscape for RF Environment

To manage warehouse operation efficiently required;
Faster data entry process
Warehouse process like, Inbound, Outbound, and Internal Warehouse Operations, SAP transactions can be executed on RF devices for example, Hand Held (terminals, barcode scanners) or fork-lift mounted. No middleware software required to connect the device with SAP.
SAP’s functionality enables real time handling of material flow system using RF scanning devices.

Types of RF Devices

GUI Devices: GUI devices uses window based operating system and the 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 graphical manner. The device is connected to SAP system as any other standalone computer.
Character Based Devices: The character based device is not connected directly to SAP but communicates via interface called SAP console. The communication between SAP console and RF device can be achieved using Telnet server. Two standard screen sizes are supported by SAP

A- RF device for forklift: 8X40 (8 lines by 40 characters)

B- Portable RF device: 16X20 (16 lines by 20 characters)

SAP Console

SAP console enables RF devices to be run within SAP applications. SAP console is used as a framework for automatic data collection in warehouse environment. SAP console translate GUI screens to character based screens that are used on a verity 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.

Components of SAP Console

The SAP console consists of four components

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: RF access point which allows for Wireless Ethernet

3) TELNET Server/ SAP Console Administrator: 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: SAP R/3 System that receives the data from mobile device.

RF in Distribution Environment

Radiofrequency is primarily used in warehouse management process in distribution environment as it efficiently handles the huge volume of transactional data processing requirements and minimized human errors. The high volume of warehouse transactions processing requirements in industries like retail, chemicals, pharmaceuticals, auto components can be handled using RF integration with warehouse management.

Goods Receipt Processes with Shipping Notifications
Goods Issue Processes for Outbound Deliveries
Internal Warehouse Processes
Stock Transfer Processes within Distribution Network
Physical Inventory Processes for the warehouses within the Distribution Network

RF Supported Warehouse Processes

A. Goods Receipt Processes with RF

RF supports goods receipt processes within 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

The warehouse workers can perform the following goods receipt-related functions;

Check all delivery items and report differences

View and changes 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 with RF

The goods issue processes are based on the outbound delivery and can be performed for the outbound deliveries identified by

Delivery number
Handling Unit Number
Staging Area
Shipment Number
Group Number

Using 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, 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.

D. Picking Process for Deliveries

Picking execution is based on transfer orders created in the warehouse management as a part of the delivery processing processes.

E. Physical Inventory

Radio Frequency Devices can be used for inventory counting, enabling a greater degree of accuracy. 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 document

RF Configuration Steps in SAP ERP WM

1) Define Profile

2) Assign Verification profile to Goods Movements Type

3) Assign Barcode type to warehouse number

4) Maintain Barcode specifications

5) Define radiofrequency Queue

6) Define Picking Area

6) Define Door

7) Define Staging Area

8) Assign Areas and Activity to Queue

Custom Development for RF Transaction

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.

Day in the Life flow using RF Technology

Warehouse Management transaction LRF1 is used to monitor the queues of warehouseperson. 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.