Paternosterregal

What is a paternoster rack?

A paternoster rack is a dynamic storage system in which shelf compartments, trays or bins are continuously circulated via a revolving chain drive. On demand, the drive rotates until the required storage compartment reaches the retrieval opening — the so-called access window. The principle resembles that of a paternoster lift: the compartments circulate in a closed loop, vertically or horizontally, without any operator needing to enter the rack itself. The system therefore follows the goods-to-person principle, reducing travel distances and error rates in picking.

How does a paternoster rack work in practice?

The system is controlled via an integrated terminal or a connection to a warehouse management system. When an operator enters an item request, the controller calculates the shortest path — i.e., whether the target compartment is reached more quickly by moving forwards or backwards. The system stops automatically at the retrieval opening. Light curtains or safety flaps prevent unauthorized access during movement. Many systems use pick-by-light displays at the access window to indicate which position within the tray is to be picked. This reduces search times and supports paperless picking. Inventory data can be managed directly within the system or transferred to a higher-level inventory management solution, enabling replenishment processes to be triggered automatically.

Paternoster racks are commonly used for small parts, tools, spare parts or archival materials. They are particularly well suited where high room heights are available but floor space is limited. Unlike static shelving or block storage, a paternoster rack makes full use of the available room height, as zones that would otherwise be difficult to access also serve as storage space.

What should be considered when selecting a system?

Before investing, the following points should be systematically evaluated:

• Load capacity and compartment configuration: Maximum compartment load, overall load capacity and flexible compartment heights must match the product range. Heavy bulk goods or large-volume items may preclude their use.
• Access safety: Operator protection through safety technology (e.g., light curtains, door interlocks) is a regulatory requirement in many industries and should be assessed independently of the manufacturer.
• System integration: The connection to an existing warehouse management system or ERP is a key factor in determining whether inventory data is available in real time and replenishment can be automated.
• Maintenance and spare parts supply: Carousel mechanisms are subject to mechanical wear. Maintenance intervals, manufacturer response times and spare parts availability are critical selection criteria.
• Space requirements and design: Vertical paternosters require sufficient clear room height; horizontal variants require more floor space. Both designs also differ in their fire protection concepts, which must be taken into account during planning.

Whether a paternoster rack is economically superior to alternative automatic storage systems — such as a vertical carousel or an automated small-parts warehouse — depends on the specific product mix, access frequency and structural conditions. A reliable comparison therefore always requires a site-specific analysis.