All PLCs must have what to operate?

To operate effectively, a Programmable Logic Controller (PLC) requires a user-developed project. This project consists of instructions and logic that the PLC must follow to perform its intended tasks, such as controlling machinery, processing data, or managing automated systems. Without this tailored programming, the PLC would lack the specific parameters and commands necessary to operate within a given application.

The user-developed project includes the application logic created using programming software, typically adhering to standardized programming languages such as ladder logic, structured text, or function block diagrams. This customized code enables the PLC to respond to inputs, execute control actions, and communicate with other devices in the system.

While other components, such as vendor documentation and network access, may facilitate the operation and integration of the PLC into a broader system, they do not define the fundamental operating logic of the device itself. Thus, the essential requirement for a PLC to function is indeed the presence of a user-developed project.