An HMI doesn't do anything — it's a pane of glass onto PLC tags. Every lamp, gauge and button on a WinCC screen is bound to a tag in the controller: the PLC writes, the screen reflects; you tap, the tag changes. Drive the tags on the right and watch the panel on the left obey — exactly as it would on the factory floor.
The left is a WinCC faceplate for one motor. The right is the PLC's tag table. There's no magic in the panel — every element just watches a tag. Toggle "Motor".running, drag the speed, raise the temperature past 80°C and trip the fault. The screen has no logic of its own; it only renders what the controller says.
Tap START on the panel too — it writes "Motor".running := TRUE back to the PLC, and the toggle on the right flips. Binding runs both ways: the screen reads tags to display, and writes tags when you touch a control.
That motor block isn't a one-off drawing — it's a faceplate: a reusable screen object with its own interface, like an FB for graphics. Build it once, then drop it on 30 motors and just point each copy at a different "Motor" instance. Pairs perfectly with the UDTs from the last track.
🖥️ WinCC Unified — the modern, web-based runtime (Unified Comfort Panels & PC). HTML5 screens, scalable, the current direction.
🖲️ WinCC Comfort/Advanced — the long-established panels (Comfort Panels, RT Advanced). Hugely deployed; what most existing lines run today.
An operator says "when temp exceeds 80 °C the motor must stop." Where should that interlock be programmed?