Customized display solution or off-the-shelf standard HMI?

Makers-of-things, machine builders and manufacturers of technical equipment are usually in need of providing a good user-experience when operators and users are operating their equipment or machines. To create a good graphical overview and make interaction as smooth and simple as possible. There are different ways to achieve this goal, for example by developing a customized display solution, or by implementing an off-the-shelf standard HMI solution.

In this paper, we will look at:

• When a standard HMI solution is the right choice
• The benefits of choosing a custom display solution
• The difference between the two options
• Risks and responsibilities
• The pros and cons

Off-the-shelf standard HMIs today

A standard HMI is a prefabricated product in contrast to the custom display solution, which is specially developed for a specific application. As an HMI is being prefabricated, the design, range, choice of components, etc. is fixed and the opportunities for customization limited with pre-set options to choose from. And the lifetime and updates of a standard HMI being fully controlled by the manufacturer.

There are several advantages of choosing a standard HMI solution. One great advantage is that it is already available and ready to implement immediately in an application which will reduce time-to-market. Standard HMIs have been developed and refined over time to meet the customer’s needs, and therefore offers features with a level of quality enabling a customer to determine whether a specific HMI matches the required overall quality and lifetime of the application.

Certifications for specific application areas such as e.g. marine are quite often a requirement and the level of certification differs widely among the HMIs available on the market, from basic CE compliance to conformity with the specifications of highly specialized certification societies. Vendors of HMIs often offer a range of different series of HMIs with different characteristics e.g. IP classing, which enable customers to reuse existing projects in other types of HMIs from the same vendor with virtually no re-engineering.

Connectivity is an important matter as well. HMIs are usually able to communicate directly with a variety of PLCs and other industrial controllers, and additional cloud connectivity is an increasing trend. With an option to choose an HMI with the opportunity to implement Industry 4.0 and optimize operations further, a customer is one step closer to bridge the gap between OT and IT systems. Most HMI vendors offer standard application software with ready-to-use basic and advanced functionality included. Some of the standard HMI application software packages enable engineers to add user specific functions, which typically requires programming skills.

Custom display solutions are perfectly tailored

You don't have to own a tailor-made shirt to understand that it will not only look better, but also fits perfectly and thereby is more comfortable to wear. The situation is similar with custom display solutions. When a custom display solution is being developed, the customer requirements can be taken exactly into account, offering you a solution which is customized to fit the application perfectly.

A display solution is similar to a standard HMI by being the user interface that connects an operator or user to the controller for an industrial, commercial or technical system. Display solutions differ from HMIs by being specifically tailored in terms of all the included sub systems e.g. the display itself, the cover lens, the required touch sensor, interface board, the SCB, the firmware and software, the enclosure, etc. to match the exact customer needs. There is even the option of including the customers branding in all parts of the solution.

When opting for a display solution, the customer has the possibility to create a solution with a complete match of requirements by access of choosing technology on all levels including operating system and application software. Customers often wish to implement their own application software and display solution vendors are typically capable of optimizing the firmware and operating system to fully support this.

Developing a custom display solution is an advantage as well as a challenge since the customer, in collaboration with the manufacturer, need to make deliberate decisions on many levels to obtain the required product quality, user experience and cost. Choosing a display solution is a commitment, and when handled skillfully by both parties can create an extremely perfected solution providing the required look and feel for an application. The challenge can be drastically minimized when choosing to work with an experienced manufacturer.

An experienced manufacturer will be able to suggest best practices, adopt experiences from previous projects and in many cases incorporate tweaked parts of previous designs, and thereby help the customer go to market faster.

The pros and cons

Here you will find an overview of pros and cons for standard HMI system versus custom display solutions:

Conclusion

What is the best solution for you is not a simple answer and depends strongly on your goals and wishes. Beijer Electronics is specialized in manufacturing both standard HMIs and custom display solutions with more than 30 years of experience within the industry. We will be happy to discuss and advise you on the right choice and give you tips so that you can achieve an optimal result.