Metalworking Production and Purchasing Magazine Profiles Warehouse Control Systems

Leading Manufacturing journalist, TR Cutler profiled the vital changing role of warehouse control systems in the current issue of Metalworking Production & Purchasing. According to Cutler, “Defining a Tier 1 warehouse control system (WCS) is necessary for appropriate technology selection. Distributors and manufacturers handling distribution functions are seeking guidelines and criteria to determine if a generic warehouse management system (WMS) sold with a new enterprise resource planning (ERP) will suffice; it will not and here is the explanation. The primary feature of WCS is its control capabilities versus simply a visual interface as provided by a human machine interface application. The primary objective of WCS is to manage the routing of product, work-in-process, and inventory through a network of material handling equipment. Other features of WCS are that it provides a uniform interface for a variety of equipment to the upper level management systems; it is highly modular with the ability to be easily reconfigured to adapt to changing business requirements or layouts; provides both historical and real-time information; and enables real-time control decision based on data-centric information.”

The distinctions between a WCS and a WMS are significant. The role of WMS comprises responsibility for the entire warehouse; material handling automation, and static locations. WMS also acts as a business system focusing on the “business needs” of the warehouse. At the same time, WMS maintains a vast amount of information such as inventory data, customer orders, and historical data. It processes large amounts of data in a non real-time mode to arrive at the daily workload of what is to be processed by the material handling system on a day-to-day basis. WMS employs highly standardized software products that provide well defined services. Customized modifications to WMS can be extremely costly and threaten future upgrades and support.

Machine Controls/programmable logic controllers (PLC) are responsible for a localized area of the warehouse, such as a conveyor segment, machine (crane, carousel, palletizer) and are focused on the mechanization and implementation needs of the warehouse. However, machine controls/PLCs are bit manipulators not data manipulators. They lack functionality to handle data strings and files. Other features of machine controls/PLCs include being able to respond to events in real-time; custom programmed to the warehouse site; and are developed in a technician friendly language (ladder logic), which allows for easier trouble-shooting techniques.

According to Jerry List, vice-president of QC Software (www.qcsoftware.com), “The integration of functionality occurs because the warehouse control systems’ scope encompasses the entire material handling automation. It coordinates the interfaces between the various localized automation controllers, such as conveyors and AS/RS (Automated Storage and Retrieval Systems). The WCS also establishes data management responsibilities in real-time and accomplishes this by working with a subset of data provided by the WMS. Unlike the WMS, the WCS is a modular control system that is custom configured to plant layout; it provides a combination of Supervisory Management screens as well as Diagnostic utilities for the warehouse technicians.” Typically, a WCS is for high volume distribution centers; companies that process thousands or orders per day and utilize conveyor. There are corresponding technology features that must be identified to ascertain Tier 1 WCS standing.

QC Software is the leading provider of Tier 1 warehouse control systems to the warehousing and distribution industries. Since 1996, QC Software, utilizing state of the art technology combined with extensive research, development, and rigorous testing, has developed the QC Enterprise suite of products. Designed to be modular in nature, easily configurable, and platform independent, this highly scalable solution satisfies the needs of any size warehouse.