Programmable Logic Controller (PLC)

Definition

A PLC is an industrial computer that reads sensors, runs control logic, and drives actuators to automate machinery and processes with high reliability and deterministic timing.

Examples

• A bottling line uses a PLC to read photoelectric sensors, count bottles, and coordinate conveyors and fillers.
• A water treatment plant PLC adjusts pump speeds and valve positions based on level and flow sensors.

Discover 🔎

PLCs are the workhorses of industrial automation. Built to survive harsh environments, they provide predictable, repeatable control for motors, valves, heaters, and other field devices. Operators interact with PLC-controlled processes through HMIs, while engineers program and maintain PLC logic using vendor tools. In many facilities, dozens to thousands of PLCs coordinate production, safety, and quality.

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