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After initial setup, the browser automatically launches with the assigned web link, so the operator gets to needed information much faster.

How Web Client Computers Help Integrate Web-Based HMI/SCADA Applications

June 20, 2024
Flexible web client computers specifically designed for industrial manufacturing environments act as Human Machine Interfaces (HMIs) to web-enabled devices and HMI/SCADA applications.

Operators in manufacturing facilities have long depended on Human Machine Interfaces (HMIs) to offer a visual summary of process systems that simplify the monitoring of crucial status and control data. A well-crafted graphical user interface enhances situational awareness, decreases workload, and lets operators oversee the entire process—helping to quickly address any abnormal scenarios.

Most of this HMI/SCADA software runs on a dedicated computer system. “Today, sophisticated web server technology facilitates access to HMI screens and the viewing of SCADA systems. Newer PLCs and RTUs frequently incorporate web servers that allow diagnostics and monitoring via browsers as well,” says Paul Shu of ARISTA Corporation, a leading provider of computing platforms and visualization display products for manufacturing environments across all industrial sectors.

Implementing Web-Based HMIs

Historically, HMI/SCADA client software has run on a dedicated computer with a compatible Operating System installed that exhibited slow loading times during startup and restart procedures. This reduced productivity on a routine basis, cutting into valuable production time. Updating and maintaining software on individual PCs resulted in a higher cost of ownership and even more downtime.

Fortunately, web-based applications have revolutionized accessibility by enabling connectivity from any location using a web browser. Still, for manufacturers, the integration of the HMI presented several challenges.

When standard web browsers are used, operators must open a browser and type a long website address to be routed to a specific program. Users have the liberty to explore various unrelated websites as well, but this only exposes the system to potential risks inherent in online browsing activities.

Now manufacturers can optimize operations by using software-enabled web clients to streamline web-based HMI implementation. The best solutions involve touchscreen displays that can serve up HMI pages on multiple monitors, in multiple split-screen configurations, or at cloned workstations to streamline the management of equipment across the production line.

ARISTA, for example, has introduced a web client computer called Q8 Edge that is designed to serve as the display or control panel for web-enabled PLCs, HMI systems, and IP cameras.

In the case of the Q8 Edge web client, ARISTA designed the interface to automatically connect with the assigned web pages without opening a browser and entering an address.

“After initial setup, the browser automatically launches with the assigned web link after turning on the PC’s power or restarting the system, so the operator gets to needed information much faster,” says Shu. 

Hybrid remote desktop services (RDS) and web-based applications can also be launched simultaneously when needed. The web client supports clones, duplicate screens, and multi-screen. Touchscreen is supported as well. 

The applications can be displayed one by one by toggling a hotkey, or all applications can be displayed by split screen. For data security, the USB drive function is disabled automatically after the system boots up. No external USB drive can be used to download or upload data. 

In addition, ARISTA prevents access to other sites or browser features. “The operator can only see what is displayed on the screen and cannot change anything beyond the intended HMI pages,” says Shu. 

When troubleshooting is necessary, the Q8 Edge can be securely accessed using interactive remote mirroring by an administrator.

The approach facilitates the installation of a wide range of pharmaceutical cleanroom-grade computers, panel PCs, monitors, and KVM. To promote efficient use in space-constrained areas, various types of mounts are available, including pendant arm, wall, pedestal, ceiling, and VESA. 

When web client computers, panel PCs, or mobile workstations must be customized to the manufacturer’s process, this can be accommodated as well. 

“If there are unique requirements such as space constraints, we can meet with the manufacturer to fully understand the situation and design a solution,” says Shu. “In six to eight months, we can deliver the first articles for approval, and begin production of the equipment.”

As manufacturing facilities continue to actively explore new avenues to enhance productivity, the use of web-based HMIs on industrial-grade computers can significantly boost efficiency. This solution, characterized by streamlined and adaptable display features as well as improved security measures, can enhance the profitability and productivity of plant operations in the years ahead.


For more information, contact ARISTA Corporation at (510) 226-1800, e-mail [email protected], or write to 48460 Lakeview Blvd., Fremont, CA 94538.

About the Author

Del Williams

Del Williams is a technical writer based in Torrance, California. He writes about health, business, technology, and educational issues and has an M.A. in English from C.S.U. Dominguez Hills.