The Difference Between a WCS and a WMS

The Difference Between a WCS and a WMS

The objective of this article is to educate the readers on the differences between a Warehouse Managment System and Warehouse Control System, help you determine if you can benefit from a WCS, and if so, how to get started. What this webinar is not is an opportunity to bash WMS or show that one is better than another. They each have their place in the enterprise. Now lets take a look at:

  • The Role of a WMS
  • The Role of a WCS
  • The relationship between WMS and a WCS
  • An example of a WCS
  • Do you need a WCS?
  • How to explain a WCS

The WMS acts as a planning system for the “needs” of the warehouse, that the ERP system doesn’t handle and wasn’t designed to handle. As the “System of Record for the Warehouse” the WMS maintains and manages a vast amount of information on inventory, and historical data. The WMS processes large amounts of data in a relative real-timemode to arrive at the daily workload of what is to be processed by the material handling systems and labor resources on a day-to-day basis. The WMS manages the non-automated operations in a Distribution Center and is software that is complex codes that link to many processes (both within the WMS and into the ERP System). Customized modifications to WMS can be extremely costly and threaten future upgrades and support. Once you start down the path of customizing a WMS, it is hard to get the benefit of new standard functionality due to cost of upgrades.

Warehouse Control Systems , or WCS; emerged to bridge the gap between higher level information systems, such as Warehouse Management Systems, and the warehouse floor by allocating, balancing, managing, and monitoring tasks executed by various automated material handling systems, equipment and subsystems such as sortation systems, in real time. Using established business rules, and the real time data, a Warehouse Control System synchronizes the activities of multiple automated equipment subsystems, human processes, and material flow, and drives control decisions and exceptions.

  • A WCS provides a simple interface for a variety of equipment to the upper level management systems such as WMS or ERP system.
  • A WCS optimizes equipment utilization
  • A WCS operates within the four walls of the warehouse and the system is typically resident in the facility. Modular in nature, a WCS is easily configurable (not customized) to meet the unique, and ever-changing business process requirements of the warehouse.

Let’s take a look at an example:

    • WMS provides picking assignments. WCS manages the flow of picked totes out to the Sorter.


    • A pack wave of 9-13K units must be completed every 30 minutes in order to stay on schedule.


    • WCS helps to measure performance to schedule for picking (both targeted and actual start / finish time for each pick wave). A daily execution schedule tool was one of the major gaps in the WMS.


    • Managing the execution of packing sorter waves was a large part of the WCS. The WCS controls the movement of waves of pick totes through the conveyor system. A new wave can move forward only when a previous wave has completed.


    • At the dispatch central sorter the WCS decides whether each pick tote can proceed to the packing sorter on an available set of conveyor lanes, or should the tote be sent to the miniload to wait. (Dr’s waiting room).


    • WCS allows the user to control the packing sorter and the conveyor through 1 system and 1 screen. Multiple pieces of MHE (Miniload, dispatch sorter, tote dump sorters and checkpoints, packing sorter) are required to work together to advance a wave.


  • Each 30 minute wave is 9-13K units in 300-500 totes and is sorted to 700 chutes.

Now you ask, “Do I need a Warehouse Control System”. Here are some things to consider or ask yourself:

  • Is your current process is inefficient and it takes too long to get a product out the door?
  • Does your conveyor system have cartons everywhere, but going nowhere fast?
  • Are you creating back orders even though the product is in stock?
  • Are you shipping the wrong products, the wrong quantities or to the wrong location?
  • Is your order profile changing; More orders, Smaller orders, Fewer lines per order?
  • Are you shipping customized orders (Value Added Services, customer specific paperwork, Labeling, Cartonization)?
  • Does your current operation require too many “work-arounds”?
  • Are you unable to measure & track individual and overall productivity?
  • You’re growing fast and can’t handle the volume, without adding more people and more space?
  • Is it getting expensive to keep modifying your WMS system to meet your operational requirements?
  • Is your information flow not automatic?
  • Do your employees travel long distances between actions?
  • Are too many SKU touches are required?
  • Are you picking SKU’s in item number sequence rather than optimized pick path?
  • Are you still using paper for directing activities?
  • Are you adding automation and equipment to your process?
  • Is there a need for a lot of decision points?

There is no magic number, for example, you need a warehouse control systems if 5 or more of these are true. You need to look at the impact of each of these on your business, the improvement and benefits a WCS can provide weighed against the cost.

As a re-cap, lets take a look at the roles of the WCS vs WMS;


  • Good for planning your business
  • Managing non-automated operations
  • Multiple facility management
  • Good at managing the expected
  • Highly standardized, well defined functionality and can be expensive to change


  • Great for executing your business
  • Ideal for controlling automated equipment, human resources and operations
  • Use of real time data and business rules to control and execute activities in your Distribution Center
  • Modular, highly configurable and inexpensive to change.

When it comes down to cost, I highly recommend getting a fixed price from WMS & WCS vendors. Do not accept T&M