What a WCS does
A WCS sits between the business logic and the machines:
- It receives a task, such as “store this pallet” or “bring tote 1042 to station 2”.
- It decides how: which aisle, which lift, which conveyor branch, in what sequence.
- It sends commands to the programmable logic controllers (PLCs) that drive the motors.
- It receives status, scans and alarms back and updates the picture.
The core of a WCS is often called the material flow controller. See What is a material flow controller?
What a WCS does not do
A WCS does not decide what the customer ordered or which batch to ship. It does not run cycle counts or reconcile stock with the ERP. Those are warehouse management tasks.
Why the boundary causes problems
When WMS and WCS come from different vendors, every task crosses an interface. Each side has its own stock picture, its own error handling and its own screens. Exceptions, such as a tote that fails a scan, must be resolved in two places.
Kulmen removes that boundary: the same platform that reserves the stock controls the AS/RS, conveyors and PLCs. Read more about machine orchestration.