Pick-by-Light
Also: Pick by Light, PbL, Lichtkommissionierung, lichtgestützte Kommissionierung, Light-Directed Picking, Pick-by-Light-System, Pick-by-Light-Verfahren
AI-generated
Pick-by-Light is an order picking method in which light modules mounted at storage locations indicate the pick position and quantity, with each pick confirmed by pressing a button or triggering a sensor. The method replaces paper- and scanner-based guidance with visual signals directly at the storage location.
Key facts
- Pick-by-Light guides pickers via light modules directly at the storage location, with no scanner or paper list required.
- The method is particularly well suited to high-frequency zones with a small number of fast-moving SKUs.
- Every storage location requires its own module, which increases investment costs for large assortments.
- WMS integration is more complex than with scanner- or voice-based methods and must be planned at an early stage.
- Put-to-Light operates on the same principle but guides the distribution of items to destination locations rather than their retrieval.
What is Pick-by-Light?
Pick-by-Light refers to a light-assisted order picking method in which electronic display modules are mounted directly at storage locations. As soon as an order is transmitted from the Warehouse Management System (WMS), the corresponding modules illuminate and show the picker the quantity to be retrieved. After retrieval, the picker confirms the pick by pressing a button or triggering a sensor on the module – the system registers the completion and advances to the next step.
Communication between the WMS and the light modules takes place via a bus system or a wired network controlled by controller units. Modern systems also support wireless connectivity. The modules themselves are typically straightforward in design: an LED display for the quantity, a confirmation button, and optionally an error button for reporting discrepancies.
Practical Applications
Pick-by-Light is particularly well suited to warehouse zones with high pick frequency and a manageable number of SKUs per zone – for example, fast-moving items in small parts storage, retail order picking, or e-commerce fulfillment. Since travel distances are kept short and guidance requires no scanning step, picking performance can be noticeably improved compared to paper-based methods. At the same time, error rates decrease because pickers do not need to interpret a list or scan a barcode.
In practice, Pick-by-Light is frequently used in combination with other methods. A typical scenario is pairing it with batch picking: multiple orders are processed simultaneously, and color-coded order displays help assign picks to the correct totes. Put-to-Light operates on the same principle but in reverse: here, the modules guide the distribution of retrieved items to destination locations or shipping containers.
Selection Criteria and Limitations
Several factors play a role during implementation that you should carefully weigh:
- Investment per storage location: Every storage location requires its own module. For large assortments with many slow-movers, the method is often not economically viable.
- WMS integration: Connecting to the existing WMS is technically more complex than with Pick-by-Voice or Pick-by-Scan. Interfaces and data formats must be clarified in advance.
- Maintenance and spare parts: Modules and cabling are subject to mechanical wear. The availability of spare parts and dependency on a single vendor should be secured contractually.
- Scalability: Assortment expansions require additional modules and potentially adjustments to the control infrastructure.
- Ergonomics: The mounting height and readability of the modules affect working conditions, particularly during long shifts.
Compared to Pick-by-Voice, no headset is required, which can be an advantage in noisy environments. Pick-by-Scan offers greater flexibility when storage locations change frequently, but requires a scan per pick. Which method is the right fit depends on assortment size, pick frequency, environmental conditions, and available budget – a blanket recommendation is not possible.
Related terms
- Akustische Kommissionierung
Acoustic order picking is a paperless picking method in which warehouse employees receive pick instructions via voice and confirm each step using spoken responses. Both hands remain free throughout the actual picking process.
- Augmented Reality
Augmented Reality (AR) overlays the real environment in real time with digital information such as text, graphics, or 3D models. In intralogistics, AR primarily supports picking, maintenance, and the onboarding of new employees.
- Automatiklager
An automated warehouse is a fully or partially automated storage system in which the receipt, retrieval, transport and management of storage units are carried out without manual intervention, using conveyor technology, storage and retrieval machines, and a higher-level control software.
- Automatisches Kleinteilelager (AKL)
The Automated Small Parts Warehouse (AKL) is a fully automated storage system for totes, trays and small parts, in which storage and retrieval operations are performed without manual intervention by stacker cranes or shuttle systems.
- Barcodescanner
A barcode scanner is an optical reading device that captures printed barcodes and converts them into machine-readable data. It is used in intralogistics for the seamless identification of goods, load carriers, and storage locations.
- Batch-Kommissionierung
Batch picking is a method in which multiple customer orders are consolidated into a single pick run. This allows the picker to travel one route while simultaneously covering positions from different orders.
- Beleglose Kommissionierung
Paperless picking refers to the assembly of orders in the warehouse without paper pick lists, where all instructions are transmitted digitally via terminals, displays, voice, or optical signals.