HMI
(Human Machine Interface) The user interface in a manufacturing or process control system. It provides a graphics-based visualization of an industrial control and monitoring system. Previously called an "MMI" (man machine interface), an HMI typically resides in an office-based Windows computer that communicates with a specialized computer in the plant such as a programmable automation controller (PAC), programmable logic controller (PLC) or distributed control system (DCS). Contrast with OI. See PAC, PLC, DCS, GUI and user interface.
In the Office
Typically located in an office, an HMI offers the same rendering capability found in today's graphical user interfaces. Designed by RCK Controls, this is a partial screenshot of an HMI used in the recovery filter operation at the Georgia Aquarium in Atlanta. (Image courtesy of Opto 22.)