What does the term “HMI-PLC communication” encompass?

The term “HMI-PLC communication” refers specifically to the interaction that occurs between the Human-Machine Interface (HMI) and the Programmable Logic Controller (PLC). This communication is vital for operational control, as it involves the exchange of data and commands between these two systems. The HMI serves as the user interface, allowing operators to monitor and control the processes managed by the PLC. Through this communication, operators can send commands to the PLC to start or stop operations, modify machine settings, and retrieve status information, which is essential for effective monitoring and control of industrial processes.

The other options focus on areas that, while important in automation, are not directly related to the interaction between HMI and PLC. Calibration of sensors pertains to ensuring measurement accuracy, storage of operational data relates to how the PLC retains information for future reference and analysis, and firmware updates are associated with enhancing the software capabilities of HMI devices rather than the communication protocols between HMI and PLC.