A Human Machine Interface is an interface that allows a user to interact with a machine. Find out everything you need to know about this technology in almost all industries: definition, functionalities, use cases…
A Human Machine Interface (HMI) is a user interface for connecting a person to a machine, system or device. In theory, it is therefore possible to use this term to define any screen that allows a user to interact with a device. However, it is generally used in the context of an industrial process.
Other terms can also be used to designate this technology: Operator Interface Terminal, Local Operator Interface, or Operator Terminal. On the other hand not to confuse GUIs with Graphical User Interfaces (GUI). These are often used within a GUI interface for visualization purposes.
HMIs can take different forms. They can be screens directly integrated into machines, computer screens, touch-sensitive tablets, and much more. Whatever the form, however, the purpose of these interfaces remains the same: provide insights into machine performance and progress.
Human-machine interface: what is it for?
In an industrial context, HMIs can be used for several reasons. They can be used to display data visually, or to track production times or trends. They can also be used to monitor performance indicators, or to monitor machine inputs and outputs. These are just a few examples, but they can also be used for other purposes. HMIs can have many other use cases.
The operator of a plant can, for example, use an HMI to monitor and control the temperature of an industrial water tank, or to check whether the various pumps in the complex are working properly. These interfaces therefore serve as gateways between operators and industrial equipment.
Who uses human-machine interfaces?
HMI technologies are used in almost all industrial companiesand by other companies, in order to interact with machines and optimize industrial processes. Human-machine interfaces are used in the energy, food, manufacturing, oil and gas, energy, recycling, and transportation industries, among others.
The people in charge of using HMIs are mainly, operators, system integrators, and engineers. (especially control system engineers). They use these interfaces as essential resources for monitoring processes, diagnosing problems, and visualizing data.
What is the difference between HMI and SCADA?
HMIs are close to SCADA systems (Control and Data Acquisition System), and is often used simultaneously within an industrial control system. However, they have several differences.
HMIs are mainly used to display information visually to allow the user to supervise an industrial process. SCADA systems, on the other hand, have a greater capacity in terms of data acquisition and control system operation.
Unlike SCADA systems, HMIs do not allow the collection or recording of information. Nor can they connect to databases. They are communication tools operating as part of (or in addition to) a SCADA system.