HMI & Operator Displays FAQ
What is an HMI?
An HMI (human machine interface) is a user interface or dashboard that provides a visual representation of the status of a control system with real-time data acquisition. In essence, HMIs are designed to connect the person with the machine or system they oversee.
What are the different types of HMI's?
There are three basic types of HMIs: the push-button replace, the data handler, and the system supervisor.
The Push Button Replacer takes the place of LEDs, On/Off buttons, switches, and any mechanical device that performs a control function. These mechanical devices can be eliminated because the HMI provides a visual representation of all of them on its LCD screen, while performing the same functions.
The Data Handler functionality is used in applications that require constant feedback and monitoring. HMIs that serve as data handlers come equipped with large capacity memories.
The System Supervisor HMI works with SCADA (Supervisory Control and Data Acquisition) and MES (Manufacturing Execution System) to display information. These are centralized or distributed control systems that monitor and control entire sites or complexes of large sub-systems spread out over large areas. An HMI is linked to the SCADA system’s databases and software programs to provide real-time trending, diagnostic data, and management information.
What are the functions of an HMI?
An HMI is used for three primary roles: replacing push-buttons, data handling, and system supervision. The push-button replacer function takes the place of LEDs, On/Off buttons, switches, or any mechanical device that performs a control function.
Data handling is used in applications that require constant feedback and monitoring. When an HMI works as a system supervisor it works with the SCADA (Supervisory Control and Data Acquisition) and MES (Manufacturing Execution System) to display information.
What are the benefits of an HMI?
The benefits of utilizing an HMI include:
- Reliable messagings and alerts
- Easier overall management of plant operations
- Increase operator confidence and cooperation
- Reduce material losses by reducing scrap
- Reduce downtime by providing faster diagnostics and alerting
- Enhance product quality through closer monitoring of product parameters
- Reduced operating costs by replacing mechanical devices and their installation accessories
HMI systems can be used in any application where one of the three functions is needed (push-button replacement, data handling, system supervision). They can be used in industries like industrial and building automation, medical, food and beverage, automotive, and appliance.