For what purpose is an HMI commonly used in conjunction with a PLC?

An HMI (Human-Machine Interface) is primarily used to provide a user interface for interaction between operators and machinery controlled by systems like PLCs (Programmable Logic Controllers). It allows users to monitor system status, visualize processes, and interact with the control system in a user-friendly manner.

The HMI translates complex data from the PLC into visual formats, such as graphs and alarms, enabling operators to understand and control processes without needing in-depth knowledge of the underlying programming or automation logic. This ease of access supports efficient operation, quick decision-making, and effective troubleshooting.

While HMIs can indeed play a role in enabling automation tasks, conducting system diagnostics, or storing data logs, these functions are typically secondary to their primary purpose of facilitating human interaction with the machinery. Therefore, the main goal of using an HMI in conjunction with a PLC is to enhance operator engagement through a visual and intuitive user interface.