An HMI (Human-Machine Interface) is the operator touchscreen on a machine. Replacing one is different from most parts because the screen runs a project file — so software compatibility matters as much as the hardware.
Stay in the same family for the project
The application running on the HMI was built in the manufacturer's software (Siemens WinCC/TIA, Allen-Bradley FactoryTalk, Pro-face GP-Pro, Weintek EasyBuilder). The simplest replacement is the same brand/series so the existing project loads with minimal changes — switching brands usually means rebuilding the screens.
Match the hardware
- Screen size and resolution: 4", 7", 10", 12", 15".
- Series: e.g. Siemens Comfort vs Basic, Allen-Bradley PanelView 800 vs Plus 7.
- Communication ports: Ethernet, serial (RS-232/422/485), USB — must match how it talks to the PLC.
- Supply voltage: usually 24V DC, and the panel cut-out size.
Have the project file ready
Before swapping, make sure you have a backup of the HMI project — without it, a new panel will be blank. If you don't have it, the program can sometimes be uploaded from the old unit if it still powers on.
Send us the model
Give us the HMI part number (and whether it's discontinued), and we'll source the same model or advise the manufacturer's successor, then quote it with availability and lead time.