You want to control and monitor your machine or line, but do you need an HMI screen on the machine, or a SCADA supervision on a PC? Both are for "seeing and commanding", but not at the same level.
The short answer: an HMI is a touch screen on the machine, for the operator, locally. A SCADA is centralised PC supervision of the whole installation, with history and alarms. Often, the two work together.
HMI: control a machine, locally
The operator panel (HMI) is mounted on the cabinet or the machine. It shows status, faults and settings, with buttons and recipes, and connects directly to the PLC. It's the right fit for one machine or station.
SCADA: supervise the whole installation
SCADA is software running on a supervision PC. It gathers several PLCs and machines, records history (trends, production), and manages alarms and traceability. It's the right fit for a full line, a pumping station or several machines.
Which one to choose?
- A single machine → an HMI is often enough.
- Several machines, need for history and reports → a SCADA.
- Many installations use both: a local HMI on each machine, a central SCADA to see everything.
And communication?
HMI and SCADA talk to the PLCs over Profinet, Modbus or Ethernet. Reliability and display speed often come down to this: a well-designed network avoids freezes.
How MTE can help
We develop your HMI screens and your SCADA supervision (pages, alarms, recipes, history) and connect them to your Siemens, Schneider, Omron and Fatek controllers. See our services or try our calculators.
👉 An HMI or SCADA project? Tell us about your machine or line on WhatsApp — we'll propose the right solution.
Frequently asked questions
Can a SCADA be added to an existing installation? Yes, without changing everything: we connect to the PLCs already in place and build the supervision on top.
Can we keep the HMI and add a SCADA? Yes, the two coexist well: the operator keeps the local screen, the manager sees everything on the SCADA.
Is a dedicated PC needed for SCADA? It's recommended for reliability. We advise on the hardware based on the size of the installation.