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What is HMI Software

How to Choose the Best HMI for Your Company

By Telstar Inc |

Whether you’re looking to upgrade your day-to-day operations or want more efficient data management and communication, HMIs are often the leading solution for most problems like these.

“The most valuable aspect of HMI technology is the ability to closely monitor production and respond to changing production demands, which improves efficiency and decreases downtime,” says Reid Beilke, an industrial personal computer product specialist. “These benefits are a result of improved diagnostics and monitoring.”

While it could go without saying why HMI systems are advantageous to any company, it’s best to be sure that you understand the ins and outs of HMI, its capabilities, and what you need from this type of software to select the right one.

What Is HMI Software?

Human-machine interface (HMI) software is one of the most influential and developing types of technology in the world. Currently a multi-billion dollar industry, HMIs are continually changing and evolving into more significant and versatile products to satisfy businesses and users from all walks of life.

HMIs are a type of interface that permits interaction between humans and machines. While the average person uses them every single day, they’re also used in all types of industries, like healthcare, automotive, power plants, food service, and more. But what makes HMIs work so well are these two essential components:

What is HMI Software

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  • Input: The input is how the human user tells the machine what they want it to do. Communication with the machine is where the user-end of the HMI comes into play. You might use keyboards, buttons, touch screens, joysticks, mice, or switches.
  • Output: The machine has to keep the user updated on the progress of commands. Using the same HMI, the machine communicates with the user to display information via status lights, valves, or sounds.

HMIs are everywhere. In fact, you’re using one right now: Your computer screen or touchscreen cellphone are excellent examples of everyday interfaces. So when installing this software for your company, how do they actually work within a computer system?

How Does It Work?

Whether your company is using a SCADA (Supervisory Control and Data Acquisition) system or relies on their PLCs (Programmable Logic Controller), the HMI has to communicate with the inner computer system to help carry out commands. This usually means that HMIs directly communicate with a PLC, which is an essential key in daily operations for most industries.

How Does HMI Software Work

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For example, when the human user sends a command via HMI, the HMI then needs to send that same command to the PLC. The PLC receives this information, processes it, and carries out the request. When the command is working or completed, the HMI signals the human user the status of the command. A simple example might be pressing a button to turn on the system. The HMI communicates this request and the PLC carries it out. In turn, the HMI shows the user that the system is on, usually with some kind of visual or auditory confirmation, like text, lights, or sounds.

Benefits of HMIs for Your Company

When choosing an HMI system for your company, it’s wise to take some time to evaluate whether or not these significant benefits can help enhance your day-to-day productivity.

There are dozens of reasons why HMIs are beneficial for any business. Still, for many, the most appealing reasons are due to its secure communications, simple data management, and cost-effective capabilities.

Benefit #1: Easy Communications

The most appealing thing about HMIs is the ease of communication. Think of it this way: It wasn’t until 1956 when researchers began experimenting with direct keyboard input to computers, which ultimately changed the way these machines evolved over the next several decades. Communicating with the computer suddenly became incredibly easy—and ultimately life-changing.

Moreover, HMIs are simple to use because they can display data visually, report progress with ease, alert any issues or changes in the machine, and streamline every necessary element. Today, HMIs can communicate effectively with the user to explain any interruptions, costs, issues, and the reasons why, thus bringing enhanced precision and reliable information.

Benefit #2: Data Management

HMIs help cut out the manual work needed for documentation and data-keeping. The HMI helps optimize and automate almost everything, which in turn cuts down unnecessary manpower costs. For example, in healthcare settings, data quality assessments (DQA) are easily stored in a virtual cloud of data that is accessible via the HMI, ultimately allowing accuracy, consistency, and timeliness of reports.

Benefit #3: Cost-Effective

Whether you’re operating a small business or a large industrial company, switching to HMI software is one of the best decisions for your budget. Although installation costs may be costly at first, businesses are likely to recover the invested money within two years of full operation. This route allows your business to go paperless and eliminate any fear of losing relevant data or paperwork.

Choosing the Best HMI For Your Company

Ensuring that you’re getting the right HMI system based on your needs is imperative. This short guide can help you narrow down the type of HMI your company may require, starting with selecting the right type, deciding how it may be used daily, and evaluating your needs.

Step #1: Selecting the Type

HMIs come in all shapes and sizes, but at the end of the day, there are only three types of HMI systems. All serve the same purpose—effective communication and data management—but may be better used in specific settings and purposes.

Type #1: Push-Button Replacer

The push-button replacer is perhaps the oldest and most common type of HMI. With a central control panel consisting of multiple buttons with specific functions, many factories use push-button replacers to improve productivity.

Here’s how: Workers can perform various commands through a single interface—or in other words, at the touch of a button. This type of HMI streamlines manufacturing processes and increases efficiency. One of the most common examples might be the “On” and “Off” button for most machinery.

Type #2: Data Handler

Data handler HMIs are intended for industries and companies that require consistent feedback from machines. These types of HMIs are primarily used for gathering and harvesting data and are especially vital in atmospheres with large amounts of information.

For example, if a company needs to collect data from a machine or a type of equipment, it’s most likely via a data handler HMI. These HMIs allow the user to work through functions like data trends, data logging, alarm handling, and more—easily at their control.

Type #3: Overseer

Overseer HMIs are relatively new and are installed whenever SCADA or MES (Manufacturing Execution System) are also necessary. These work together in large environments to monitor expansive areas.

Overseers typically run on a Windows operating system, which allows for a visual approach between the human user and the machine with a graphical interface on an electronic display. It has several ethernet ports for communications and can look over entire sites.

Step #2: Decide How It Will Be Used

How and where your HMI will be used is one of the essential pieces of the puzzle. While you have to be sure it matches up with the rest of your systems, like SCADA or PLC, most installation companies can converge new or existing systems together without issue.

Aside from that, you also have to consider the operating environment.

Food processing plants or outdoor HMIs might require special protection, like a high ingress protection (IP) rating. The IP rating (read as “IPXX”) determines if the electrical product’s outer case can protect the working parts from water or dust to keep the product working longer.

Examples of Ingress Protection Rating Levels

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On the other hand, busy industrial settings with lots of noise or vibrations like automobile manufacturers may require a hardened industrial panel. In settings like these, you’ll want an HMI system that is hardy and ruggedized so that it can last for years through lots of substantial movement and action.

Step #3: Evaluate Your Needs

HMIs are there to make your life easier. They should be simple to use and understand, which is why the learning curve is relatively low. So when selecting the right HMI for your company, you’ll want to evaluate your wants and needs, which might include:

  • Screen size, type, and resolution
  • Internet access and tech support
  • Types of tasks to perform
  • Other systems it will connect to, like SCADA or MES

The good news is that most companies capable of installation will know exactly where to start and how to incorporate your needs. So while interviewing companies, make sure you address your needs, along with other important notes, like how it will be used.


With these critical steps in mind, you’ll have a better idea of the kind of HMI system you need. It’s ultimately best to have an experienced and professional company customize your ideal HMI based on the type you require, how you’ll use it, and other specifications.

With more than 37 years of experience, Telstar can take an idea and help turn it into a reality so that you—and your business—can operate more productively in half the time and effort. Contact Telstar today for more information.