Pick to Light / Pick to Light
Pick-to-Light consisting of compartment displays on storage compartments, belongs to the paperless picking methods and supports the picker with light when picking and removing the items, products or components. The quantity from the picking or pick list is displayed directly via the Pick to Light instruction on the removal compartment and confirmed on the acknowledgement button.
Pick to Light Procedure and how it works
A Pick-to-Light compartment display is equipped with an eye-catching light that can be seen from afar, an acknowledgement button, numerical display and other function keys. With the acknowledgement button, the order picker confirms the removal directly at the removal tray. The stock change of the quantity is sent back to the merchandise management or warehouse management system in real time and the flashing catch light with the quantity display is switched off immediately. Sometimes the compartment displays also have an alphanumeric display to show the picker additional information besides the quantity of items picked.
Plus and minus correction keys are responsible for correcting the withdrawal quantity in case of shortages or inventory functions. Additional function keys are also available for calling up special functions. Optional sensors can also be used as an alternative to key acknowledgement. They monitor the intervention in the withdrawal station and generate alarms if necessary.
The orders are activated or started via barcode scanner, RFID reader or by pressing a button. Depending on the application, the picking orders can be picked serially or in parallel after activation at the Pick-to-Light system. In the first case: only the acknowledgement of a compartment display switches on the next display on the compartment. In the second case: the Pick-to-Light system switches on all compartments simultaneously.
Connection of the Pick-to-Light system
The flexible connection of the Pick-to-Light system to a higher-level system is crucial for optimal operations. This can be a warehouse management system, warehouse management system or ERP programme. The advantages of a simple and fast interface are essential and have a great influence on many functions in the entire process.
The standard interface of the Pick-to-Light system is realised via TCP/IP socket. Two asynchronous TCP/IP channels are established for data transmission in both directions.
Communication channels to the Pick to Light
The first channel (download) is used for activating and deactivating the displays. Many parameters are included in the telegrams. The second connection channel (upload) is responsible for the acknowledgements, corrections, special messages and error messages.
A receive acknowledgement is sent on each channel. In this way, the data is transmitted quickly and very securely. More details can be found in the article: Standard interface of a Pick-to-Light system.
In many cases, the process must be optimised. We build customised connections for this purpose. Talk to us to find out even more.
A scientific short definition: Pick-to-Light / Pick-to-Light Definition.
Pick-to-Light (roughly "picking by light") is one of the "paperless" picking methods. Instead of a picking list, the items and quantities to be picked are communicated to the picker via a compartment display located directly at the picking compartment.Source: Pick-to-Light - Wikipedia
Pick-to-Light and Pick-to-Light are synonyms that we will continue to use only individually. You can read more about the history in the article: "History and development of Pick-to-Light".
The Pick-to-Light hardware guides the order picker with light and consists of compartment displays, controllers and accessories.
- Controller (communication and power supply)
- Mounting rails with integrated BUS (shown here in yellow)
- Compartment displays with signal lamps (2 x 7 colours), piece count display and an acknowledgement button
- Cabling with 4-core cable between the mounting rails and controller
How is a modern pick-to-light constructed? Where is it best used? Are there also other picking systems?
Fields of application of the professional displays
The following industries have been using our system and supporting picking tasks for many years:
- eCommerce: picking warehouse, replenishment, sorting station in the dispatch warehouse
- Automotive: Batch processing and sequencing of baskets and JIT racks for the assembly lines
- Production: assembly stations, set formation and machine placement
The pick-to-light system is very versatile as a picking method, supports the picker and avoids picking errors. The field of application is large. You can find out more details in the article: Where is Pick-to-Light used?
A Pick-to-Light system is one of the best picking systems, modular and very flexible. Mounting the displays at each picking location is easy and the subsequent conversion options are uncomplicated. Shelves or mobile constructions are ideal for this purpose.
The functions are clearly structured and the light signals are unambiguous. The system supports various barcode scanners, RFID readers and scales. Almost all displays are equipped with several additional keys to correct faulty stock (plus, minus and F-key for special functions). Some displays have only a simple signal lamp and acknowledgement button.
You can find more details in the article: Pick-to-Light System
- Sensor for automatic acknowledgement monitors access to the storage compartment (access monitoring).
- Digital I/O for receiving and transmitting external signals.
- Beep sound
The system is controlled by the LUCA software in real time. The connection to the warehouse management system, material flow and conveyor technology is made via the LUCA-Server, which controls the entire processes.
Sensor for access monitoring at the Pick to Light compartment display
The pick-to-light sensor has an important new function in pick confirmation. A sensor can be optionally installed above or below the display. The sensor monitors the accesses and automatically acknowledges the activities.
The mounting of the sensors must be precisely coordinated. The sensor as a light sensor can measure 15-20 cm without a reflection mirror. With a mirror, the sensor can even be used at 80-100 cm.
Functions during order picking
Paperless picking is based on a pick list with picking orders. The data is transmitted by the warehouse management system and distributed to the appropriate picking areas. There are many variants of how this works.
How does the system work?
The optimal picking processes are very important for a picker, his performance and quality. The picker will be guided quickly and clearly to his storage location with the help of the displays.
Afterwards, he confirms the pick with the acknowledgement button. Picking errors must be reduced to an absolute minimum. In order to design the picking processes correctly, you have to pay attention to some details.
The standard process
At LUCA, there is standard software in which the picking process already fulfils 80% of all the requirements of the pickers. The aim is to minimise the error rate and to accelerate the picking process. Very often, however, the requirements for the system are very specific.
How can the correct orders be started? Can the completeness of the last order also be checked? Basically, there are two different start methods here:
- Start via a receipt with barcode
- Paperless picking (FIFO or external trigger)
If the delivery notes, cartons or containers are marked with a barcode, barcode scanners can be used in the Pick to Light process. In this case, the displays can also be activated via the delivery note or invoice. RFID technology is also supported.
Simultaneously, Sequentially or Page by Page?
If you have already started the process, the displays on the compartments must now light up. But what is the best way to light them up? All together, one after the other, first one and then the other side of a shelf aisle? Is this batch picking?
Confirmation of withdrawal and end of order
When all items have been picked, the picker confirms the removal at the compartment with the confirmation button. This confirms the pick.
If the quantity is not correct, the correction keys (+/-) can be used to make the quantity corrections. Confirmation of the withdrawal triggers a feedback to the higher-level warehouse management system (WMS). There, the stock changes are carried out in real time.
Support in assembly and production
The work during assembly often consists of many steps. The worker must correctly reach into many containers according to the assembly instructions. An assembly process with assembly instructions on a piece of paper is not optimal. The luminous displays can significantly increase performance and quality.
You can read more about this in the article: Pick-to-Light Assembly
How good is Pick to Light and how much does the system cost?
Performance and quality are opposing parameters. As a result, the more performance is expected, the less quality the picker can deliver and error rates increase. Increasing performance and quality at the same time is not easy with any of the picking methods.
Faster and cheaper. That is the goal. The solution possibility of the control software is not everything. The simple conversion options are also important.
As a leading order picking process, Pick to Light is currently providing us with an excellent example of how performance and quality can increase rapidly. At the same time, operator guidance is improved by the light signals when there is an immediate change in stock. Picking system of a special class.
Performance increases by up to 40%. Due to the targeted support of the accesses to the storage compartment, the quality also increases by more than 15%. This minimises picking errors and teach-in time.
When using sensors, the quality increases by a further approx. 10%.
The ROI calculation and the costs
When planning the system, it is essential to consider the economic viability and the increase in efficiency. The system requires a relatively large amount of hardware, which does not make the procurement of the equipment cheap. The cost of the projects is justified by the effort put into the hardware. As a budget, calculate with 100,- € per storage compartment.
An ROI calculation must show whether the investment is profitable for the company. Get in touch with us. We will help you make the calculations and explain the details. If the demand for power is not particularly high and the storage areas are large, we also supply other technologies as an alternative.
Advantages and disadvantages
- Very low search time of the articles and increase of efficiency and productivity
- The operator has his hands free when picking and great freedom of movement
- Multilingual use with short training time for changing personnel
- Fewer pick errors from wrong items and no missing pickings
- Enables very high performance of the order picker and short throughput times in the workflow
- Fast and accurate quantity correction directly at the storage location and direct feedback of the stock change to the warehouse management system
- Relatively high acquisition costs.
- Difficult to use with free-standing pallets (special construction required).
Supplier and manufacturer
As a manufacturer, supplier and expert in picking solutions, LUCA Logistic Solutions, thanks to the LUCA communication server software, is very flexible and professional. We offer different technologies to achieve an optimal solution for the customer. We have been building our picking systems since 1998.
In logistics and production, pick-to-light is one of the best and most widely used error-free picking systems. The picker intuitively follows the light signals and quantity displays at the pick location and thus minimises his search time (operator guidance through the orders). Numeric and alphanumeric quantity displays show the number of items. In case of stock errors, the correction keys help.
The simple installation, robust acknowledgement buttons and flexible conversion options make the Pick-to-Light system very attractive. Easy connection to any warehouse management system via the LUCA-Server brings enormous advantages. The system can also support permanent inventory very well. Optimal operator guidance through customer orders is the goal.
However, in warehouses with many storage compartments, the price of mounting the displays is quite high. Therefore, it makes sense to use the system for A-items. The picking of B and C items can be supported by other, cheaper technologies and picking systems. Put-to-Light can also be used on the vehicle with WLAN in order to optimise the gripping times, travel times, etc. during picking.
The system is Industry 4.0-capable and leads the way in paperless picking.
What hardware does Pick to Light need ?
For a Pick-to-Light system, the first thing you need are the compartment displays that are mounted at each storage location. They include LED lights, quantity displays and several buttons. Another system component you need are the controllers, which are used to supply the devices with power and data. The last thing to add are the mounting rails, clamps and cables.
If you want to know more details, visit the page: Pick to Light / Pick to Light  - LUCA Logistic Solutions.
What interface does Pick to Light have to SAP?
The SAP interface is not realised directly with the hardware, but via a server. The server communicates with the compartment displays on the one hand and with the higher-level system, e.g. SAP or warehouse management, on the other.
The connection via a server can be designed flexibly with RFC, TCP/IP, databases, etc. Read more about this at: Pick to Light Picking - LUCA Logistic Solutions
Which specifications are required for a request of a Pick-to-Light system?
1. number and types of compartment displays (see: Pick to Light Hardware - LUCA Logistic Solutions)
2. number of mounting rails for attaching the modules
3. total length of the mounting rails
4. layout and functional description
5. entries on the host or warehouse management system
How does Pick to Light work ?
The Pick-to-Light compartment displays light up as soon as a picking order is activated. The indicator light signals the display position from a great distance. The withdrawal quantity is shown on the display.
Correction is made with plus/minus keys if necessary. The picker confirms the removal of goods (pick) at an acknowledgement button.
Many years of experience in paperless order picking