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Warehouse Management System

Programmable Logic Controller (PLC) vs Warehouse Control System (WCS)

Programmable Logic Controller (PLC) vs Warehouse Control System (WCS)

Some of the abilities of a programmable logic controller are similar to those of a warehouse control system software. However, they are too limited in volume of commands. Lacking a database, a PLC can only be directed for a limited number of actions. Meanwhile, a centralized WCS can feed information to devices more slowly, on a time-dependent basis. A PLC cannot meter commands like a WCS. It cannot store many commands because the database is too small.

A centralized WCS has more human-like intelligence that can orchestrate different machines simultaneously throughout a daily cycle by gathering and metering more real-time information. A WCS has this capacity due to its database size.

Combining WMS, WES and WCS

With a centralized, agnostic warehouse control system software, the need for separate WMS and WES lessens. Warehouse stock control software can be an involved task to implement. The best solution is a comprehensive package. A business can buy a package performing all three functions. Better yet, it can be a modular package. Components could be added as new needs arise. A modular WCS would be suited to the diverse needs of a distribution environment, a manufacturing environment or a corporation’s warehouse. Beyond being adaptable to the type of center, a modular WCS can scale as the business develops.

With modular options, the software expenditure can become commensurate with business needs. Why should a company pay for a comprehensive software solution when it only uses 70% of it? That vendor is over-solving their client’s software problems and needs. In effect, they are charging for unused functionality.

New ERP or ERP Expansion Considerations

When weighing options for improving control and leverage over automated equipment, many people consider ERP-based options. They think the best route would be to start moving into unused portions of their existing ERP. Many operators believe their existing ERP has additional functionality for automation that could be useful or consider upgrading it. However, an ERP is often lacking in quality warehouse control system software.

A simple WCS connected to an ERP may produce narrow results. When a WMS  is involved with the ERP, the information delivered is broader. It’s not limited by what is stored in that device.

Warehouse Control System Software Data Flow

The flow of data and commands between warehouse control system software to different locations varies depending on the type of connection. When it flows down to a device, time is a priority. Meanwhile, when interfacing to an ERP, time is not of the essence.

Data Between a WCS and a Device

An advantage of warehouse control system software sending a command to a device is that a response can return immediately. The device can quickly affirm when it will complete the task. This can happen on the scale of a millisecond. It happens in real time, using a web service, a web API or a TCP/IP interface. Faster response times keep many types of actions moving forward in a distribution center or warehouse. Databases don’t allow for a real-time interface.

Data Between a WCS and an ERP

When interfacing to an ERP, real-time interactions are not a priority. An ERP system doesn’t care when the designated action occurs. It could take place in the next 30 seconds or five minutes later. When a WCS interfaces to a device, time is a priority. The result is that a WCS provides the level of necessary responsiveness. An ERP isn’t as sensitive to time.

Cloud or Local Warehouse Control System Software

It’s important to consider whether warehouse control system software or its components should reside in the cloud. Guaranteeing responsiveness is a vital part of location considerations. Those with experience in WCS operations warn of the challenges of securing real-time interface to that piece of machinery. There are instances when dark fiber can guarantee a high level of response. In that case, a WCS that resides in the cloud can work well. However, guaranteeing real-time response with cloud-hosted databases remains a major challenge for a lot of companies.

In many cases, some components end up being housed in the cloud, while others remain local. This hybrid situation can keep operations running smoothly. Components that do not depend on a sensitive, millisecond response time can be stored in the cloud. Meanwhile, on-premises machinery interfaces can better guarantee the faster travel of information. Speed is the key.