HMI Design and Development Training: User Interface Best Practices for Reliable Power Systems

Human–machine interfaces are no longer just “nice dashboards” on the side of a UPS or inverter. In modern industrial and commercial facilities, the HMI is the primary way operators see what is happening between the utility, the UPS, inverters, and critical loads, and it is often where they must act under time pressure. When the user interface is confusing, sluggish, or visually noisy, operators lose situational awareness and reliability suffers. When it is clear, responsive, and safety focused, the same hardware delivers fewer outages and faster recovery.

As a power system specialist, I have seen both sides. Control rooms that follow high‑performance HMI practices—like those promoted by Inductive Automation, RealPars, DataParc, and the High‑Performance HMI community—tend to make better switching decisions, catch abnormal trends earlier, and recover from faults faster. Others, built without any structured HMI training, bury alarms, overload screens with color, and contribute directly to misoperations.

This article explains how to structure HMI design and development training for teams working on UPS, inverter, and power protection systems, and it distills concrete interface best practices you can apply immediately.

Why HMI Design Matters for UPS, Inverters, and Power Protection

Across manufacturing and energy, modern processes are managed through screens rather than hard‑wired push buttons. DataParc notes that poor HMI design has been implicated in serious industrial accidents, because operators could not see the right information or distinguish abnormal states fast enough. Transmission and distribution control center training from EPRI makes the same point for power grids: if OT and IT displays do not support situational awareness, decarbonized, distributed grids become harder to operate safely.

In industrial and commercial power supply systems, the stakes are similar. Operators need to answer basic questions at a glance. Is the UPS actually carrying the critical load or are we unintentionally on bypass? How much battery margin do we have right now? Are we close to thermal or current limits on any key feeder? When these answers are hidden behind five clicks, encoded in tiny fonts, or drowned in animated graphics, reliability becomes a function of luck and heroics rather than design.

At the same time, HMI hardware in embedded power devices is resource constrained. Crank Software’s real‑time HMI guidance highlights the tension between responsiveness and limited CPU, GPU, and memory budgets, especially on microcontroller‑based hardware. In automotive systems, user input should typically produce visible response within about 100 ms; that order of magnitude is a sensible goal for safety‑critical power HMIs as well. HMI training therefore has to cover both user‑experience principles and embedded performance engineering.

What Good HMI Training Looks Like in the Power Domain

Before diving into specific patterns, it helps to understand what high‑quality HMI training includes.

Short courses like Tonex’s human–machine interface program start with definitions, human factors, and interaction design fundamentals. They emphasize cognition, perception, ergonomics, mental models, and usability testing so that designers understand how real people perceive and process information. The course also surveys modern HMI technologies including touch, voice, AR and VR, and wearable interfaces, and it ties them back to integration, cybersecurity, and regulatory compliance.

Hands‑on paths, such as RealPars’ high‑performance HMI design training and skill paths on user‑friendly industrial interfaces, focus on practical screen building. Learners build multiple HMI projects using modern tools and receive step‑by‑step guidance from instructors who actively work in industrial automation. Along the way, they apply best practices in color theory, typography, layouts, alarm management, and situational awareness. By the time they receive a completion certificate, they have a portfolio of working HMIs rather than just theory.

On the programming side, SolisPLC’s HMI guides highlight that most industrial HMIs are configured visually. Control logic remains in PLCs, while HMI work centers on screen layout, binding graphic elements to PLC tags, and configuring alarms, diagnostics, and access control. Training that exposes engineers to tools like FactoryTalk View Studio or similar platforms, and to the differences between local panel HMIs and distributed SCADA‑style systems, is critical when your UPS or power protection system must integrate into a wider plant network.

Finally, user‑centric UX workbooks such as Siemens’ HMI Design Workbook push teams to treat operators, maintenance staff, and other end users as primary stakeholders. The workbook approach standardizes UX patterns across multiple machines and recommends integrating UX into the machine development lifecycle from the outset, rather than treating the HMI as an afterthought.

For a power system team, an effective training program blends these elements. Team members need grounding in human factors and safety, practical screen building skills, experience with real HMI toolchains, and a structured way to document design decisions across the entire UPS or power distribution portfolio.

Examples of Training Focus and Value

A concise way to think about the training mix is to map focus areas to the value they bring in power reliability contexts.

Once your team understands these pillars, you can turn to concrete user interface practices tailored to power reliability.

User Interface Principles that Protect Reliability

Despite the variety of industries covered by sources like Inductive Automation, Aufait UX, Eleken, DataParc, and SolisPLC, there is strong alignment on what makes a good HMI. Translating those principles into power systems is largely about deciding what to emphasize on screen.

Situational Awareness: From Raw Data to Meaning

Across multiple references, situational awareness is the central goal of an HMI. Inductive Automation defines the role of HMI as turning raw data into meaningful information and deliberately drawing attention to the most important information so operators can recognize issues and react quickly. Eleken describes situational awareness, clarity, and responsiveness as the three core HMI design principles. Dr. Mica Endsley’s work, cited by Aufait UX, splits situational awareness into perceiving relevant data, understanding what it means, and predicting what will happen next.

For a UPS or power protection interface, this means your screens must answer three practical questions without forcing operators into mental gymnastics. What is the current power path and system state? How does that state compare to normal ranges and limits? Where is it heading in the near term?

Analog and contextual displays are powerful here. Inductive Automation recommends analog displays and moving indicators instead of purely digital readouts because they provide immediate context about how far a value is from its target. DataParc suggests pairing numeric values with simple bar or gauge indicators, and placing values at their physical location in schematics. For example, a UPS battery state‑of‑charge bar that fills within a clear “normal” band and shows reserve limits is far more actionable than a standalone percentage. Embedded trends or sparkline charts, recommended by Inductive Automation and DataParc, let operators see short‑term history next to key KPIs so they can anticipate thermal overloads, rising harmonics, or battery degradation instead of reacting only to instantaneous snapshots.

When I review power HMIs, many display dozens of numbers in tables but provide no sense of trend or margin. Training that emphasizes contextual visualization—especially analog indicators and local trends—helps engineers redesign those screens so operators perceive, understand, and predict instead of guessing.

Reducing Cognitive Load and “Idiot‑Proofing” Critical Actions

Aufait UX stresses the importance of reducing cognitive load by putting data in context and aligning displays with operators’ mental models. They also discuss “idiot‑proofing,” which they define as deliberately eliminating the possibility of inadvertent critical actions. That includes adequate spacing between controls, using color to denote criticality, and sizing buttons appropriately, especially on touchscreens commonly used on factory floors.

In safety‑critical power HMIs, error prevention goes beyond convenience. The US railroad guidance in Appendix E to Part 236 insists that safety‑critical information be presented clearly and unambiguously and that control layouts reduce the likelihood of inadvertent activations or mis‑selections. Aufait UX adds concrete practices: use confirmation prompts before executing critical commands, provide clear error feedback and recovery paths, prioritize critical controls so they are distinct and easily accessible, and highlight system status in real time with color‑coded alerts.

Applied to UPS and power protection, this means actions like transferring to bypass, opening or closing key breakers, or disabling protective functions should never be a single inconspicuous tap. Training should coach designers to combine spatial separation, distinct styling, confirmation dialogs, and real‑time status feedback so that unsafe or unintended operations are hard to perform by accident and easy to recognize if they are initiated.

In practical workshops, I often ask engineers to role‑play an operator under time pressure, responding to an overload or transfer event. When they struggle to find or safely use the controls they themselves designed, it becomes a powerful training moment.

Visual Hierarchy, Color, and Emphasis

Many industrial HMIs suffer from “Christmas tree syndrome,” with every asset brightly colored and animated. Multiple sources, including Inductive Automation, DataParc, EPRI, and Aufait UX, push in the opposite direction.

The consistent recommendations are to use neutral, mostly gray backgrounds and muted equipment graphics so that the screen looks visually boring in normal operation. Bright, high‑contrast colors such as red should be reserved almost exclusively for abnormal states and alarms. Animation should be used sparingly and only to highlight abnormal conditions, not to depict normal operation. DataParc emphasizes that alarms should never rely on color alone; they should be supported by additional cues such as flashing borders or explicit alarm symbols to accommodate color‑blind users and degraded viewing conditions.

Inductive Automation describes emphasis as the intentional use of visual differences—size, color, position, and isolation—to prioritize information. They also introduce redundant coding: combining multiple emphasis techniques, for example, a large, centrally placed, brightly colored alarm indicator with whitespace around it. Aufait UX and Eleken echo the need for legible fonts, sufficient contrast, and text and control sizing that remains readable across lighting conditions. EPRI’s work on T&D control room displays even relates color usage to established codes like the Cooper Color Code to ensure that urgency levels are communicated consistently.

For power HMIs, training should walk designers through practical examples. Neutral layouts where only abnormal feeders or UPS modules light up. Alarm summary areas where high priority alarms use a combination of color, iconography, and position to stand out. Trend charts where normal bands are shown in muted tones and limit breaches use strong, consistent colors across all screens.

Navigation, Screen Hierarchy, and Information Architecture

Both Inductive Automation and SolisPLC emphasize hierarchical navigation structures. Inductive Automation describes a four‑level model: a plant or area overview for situational awareness, unit‑level control views for active manipulation, detailed views for individual assets, and support or diagnostic screens for procedures and histories. SolisPLC’s HMI design guide observes that a typical HMI might include around ten key screens—overview, settings, area screens, and device faceplates—and highlights the trade‑offs between shallow, deep, and hybrid navigation models. Shallow models provide one or two‑click access to most screens, while deep models follow the process hierarchy more strictly but can slow cross‑area navigation. They recommend a hybrid approach with hierarchical drill‑down plus direct links to related areas where justified.

Aufait UX provides more tactical navigation best practices. Keep essential buttons such as Home or main screen access consistently visible, design layouts around task frequency so that commonly used functions are easy to reach, and aim to reach any screen within roughly two or three clicks. They also stress logical grouping of related functions and the importance of usability testing to verify that navigation aligns with operators’ mental models.

For power systems, this typically translates into a top‑level single‑line or one‑line diagram showing utility feeds, generators, UPS blocks, static switches, and key load groups; area or unit screens for specific UPS systems or switchboards; and device‑level views or faceplates for breakers, inverters, and critical meters. Good training encourages teams to start from operator tasks—such as investigating an alarm, preparing for maintenance, or validating redundancy—and to design navigation that supports those sequences with minimal context switching.

Real‑Time Performance: Training Beyond the Mockup

Attractive screens that stall or lag undercut reliability as surely as poor layouts do. Crank Software’s work on real‑time HMI performance in embedded systems is especially relevant to UPS and inverter controllers, which often run on microcontrollers or low‑power system‑on‑chips.

Crank identifies several drivers for real‑time optimization: user experience, operational safety, and system efficiency. When the HMI does not respond promptly, operators may repeat inputs, misinterpret states, or assume the system has locked up. In power systems, that can lead to duplicate commands or missed actions at critical moments.

Key performance challenges include suboptimal memory use, rendering latency from complex graphics, slow data handling, poor synchronization with real‑time control tasks, and sheer processor or memory limits. Training for HMI development in power applications needs to teach engineers how to manage these constraints.

Crank’s recommendations provide a useful syllabus. On the rendering side, offload graphics to GPUs where available, preload critical assets such as icons and fonts, and choose formats carefully—vector graphics can avoid decode overhead, while heavy bitmap formats can introduce delays. For interaction latency, event‑driven architectures respond to user input immediately, whereas polling loops tend to waste CPU and introduce jitter. Touch interfaces should be tuned for sensitivity and noise cancellation, and predictive techniques can preload expected next screens.

On the data‑handling side, caching frequently used data, using lightweight data formats and parsers, and adopting a real‑time operating system such as FreeRTOS, VxWorks, or Integrity RTOS can help synchronize HMI tasks with power control loops and sensor data. Crank also recommends selecting MCUs or SoCs that match graphics and timing needs, and notes that dual‑core microcontrollers can separate UI workload from time‑critical control tasks. For memory, dynamic content such as framebuffers should live in fast RAM, while code and persistent assets can be placed in flash.

Interrupt and scheduling practices matter as well. Short, priority‑based interrupt service routines and thoughtful task scheduling with clear priorities help ensure that critical events—such as protection trips or transfer conditions—are reflected on screen without being blocked by nonessential tasks. Excessive context switching, on the other hand, adds overhead and can create subtle bottlenecks.

Finally, Crank stresses that performance testing should be done on real hardware under realistic operating conditions, not only in simulation. For power HMIs, that means exercising the interface during actual switching sequences, load changes, and fault tests to reveal driver issues, software bottlenecks, or thermal throttling behaviors in Dynamic Voltage and Frequency Scaling and power‑saving modes.

When HMI training for power engineers includes these embedded performance topics alongside UX principles, teams are more likely to deliver interfaces that feel instantaneous and trustworthy in the field.

Safety, Standards, and Regulatory Expectations

Safety‑critical sectors such as rail and power provide concrete guidance on how HMIs should behave. Appendix E to Part 236 in US rail regulations defines HMI design expectations for signal and train control systems. It treats HMIs as the full set of displays, controls, indicators, and software elements by which crews interact with safety‑critical functions. The guidance insists that safety‑critical information be prioritized over other data, presented clearly and unambiguously, and supported by alerts that are easy to distinguish from normal indications, using both visual and audible cues.

The appendix also warns against overloading operators. Interfaces should manage information density and timing so that only necessary information is presented in high‑workload situations, suppressing nonessential messages that could distract from trackside observations or physical conditions. It further recommends that failures and degraded modes be indicated clearly without conflicting or misleading data, and it encourages verification and validation through simulations, field tests, or structured user evaluations.

Aufait UX connects HMI design in industrial automation to international standards like ISO 9241‑110 on human‑system interaction dialogue principles. They note practical details such as minimum touchscreen button sizes of roughly 1.5 centimeters on the shortest side to ensure easy selection, structured dialog boxes with title bars and clear controls, and navigation models that minimize user actions and allow intuitive horizontal movement among panel sections. They describe a four‑panel layout consisting of title, information, command, and navigation panels, with the title area dedicated to essentials like communications status, date and time, and current view name.

In the power sector, EPRI’s training for transmission and distribution control centers focuses on proper color usage, trend visualization, and distinguishing optimal from suboptimal HMI designs. The goal is not to replace existing systems but to guide incremental improvements that enhance operator situational awareness and decision‑making as the grid evolves.

For UPS, inverter, and power protection HMIs, training that references these safety and ergonomic guidelines helps your team make better decisions about what to show, how to structure screens, and where to place controls for emergency and abnormal scenarios. Even if your equipment is not directly regulated under those exact rules, adopting similar principles raises the safety baseline.

Building Skills: From Concepts to Practice

Conceptual understanding is not enough. The LinkedIn framework on improving HMI design skills highlights the importance of practice through real or simulated projects. It points to an HMI Design Toolkit with templates and examples for personas, scenarios, wireframes, and prototypes, and it encourages designers to participate in communities such as an HMI Design Forum to share work and receive feedback.

In a similar spirit, RealPars’ HMI design training is built around practical examples taught by practitioners. Learners build HMIs step by step, encounter common pitfalls, and apply best practices under guidance. SolisPLC recommends a learning path where engineers start by installing HMI software, then build simple I/O screens linked to PLC tags (such as a basic traffic light example), before adding navigation, fault displays, alarms, user permissions, and more nuanced visual design like tank level bars that convey state more clearly than numbers.

Keba’s HMI design tips argue for involving external UX designers early in projects. A UX specialist can help structure the process, moderate decisions, and translate user needs into functional requirements for developers. They also emphasize carefully profiling operator groups. Experienced “old‑timers” may want access to detailed settings and diagnostics, while newer or temporary workers need simplified views for basic operation. Both groups interact with the same UPS and power equipment; the HMI must support both by offering layered access rather than a one‑size‑fits‑none interface.

In my own work with power system teams, the most effective training programs combine these ideas. Participants learn the principles, but they also redesign one of their own existing screens, test it with colleagues, and then apply lessons learned to a second, more complex HMI. That loop of concept, application, feedback, and refinement builds lasting competence.

Designing for Remote, Multi‑Device Operation

Modern HMIs rarely live on a single stationary panel. Aufait UX notes that cloud and IoT integration now demand multi‑device access, and they recommend responsive UI designs that scale across desktop monitors, tablets, and handhelds, as well as remote monitoring capabilities and consistent UI elements across platforms.

Eleken’s survey of HMI types reinforces that screens may show up as built‑in machine displays, desktop dashboards, mobile apps, voice interfaces, or web portals. SolisPLC distinguishes between local on‑machine HMIs and distributed, SCADA‑style HMIs that aggregate data across multiple devices and are typically accessed using a keyboard and mouse rather than only touch.

For industrial and commercial power systems, this means the HMI on the UPS front panel is only part of the story. Operators and engineers may also view data and alarms through building management systems, energy dashboards, or fleet‑level cloud interfaces. Training should encourage teams to think of the HMI as an ecosystem, not a single screen. Critical design questions include which states and controls belong only on local panels for safety reasons, which can be exposed to remote clients for monitoring, and how to maintain a consistent visual and interaction language so that alarms look and behave similarly across every surface.

A Practical Training Roadmap for Power Reliability Teams

Pulling all of this together, an internal training roadmap for engineers working on UPS, inverter, and power protection HMIs often progresses through several stages.

Foundation work introduces Human–Machine Interface concepts and human factors. Here, resources like Tonex’s short course and Eleken’s design overview are helpful for defining HMIs, explaining the human–machine communication loop, and covering basic principles such as situational awareness, clarity, and responsiveness. At this stage, engineers learn why cluttered, colorful, “cool‑looking” screens hurt safety and efficiency.

Design and UX modules shift focus to high‑performance HMI principles. Inductive Automation’s high‑performance HMI practices, DataParc’s color and layout guidelines, Aufait UX’s best practices, and Siemens’ workbook together teach neutral, context‑rich design; disciplined color use; analog and trend‑based displays; and navigation hierarchies. Teams learn how to align interfaces with operator tasks and mental models and how to reduce cognitive load and prevent errors.

Hands‑on HMI programming and architecture sessions teach team members to implement designs in actual tools, tying in SolisPLC’s guidance on visual development, local versus distributed architectures, and navigation models. Engineers map screen elements to PLC tags, set up alarms, and experience firsthand how terminal size, memory, and processor resources constrain design. They practice designing for small local panels and then for larger SCADA‑style views.

Safety, standards, and verification modules connect what the team builds to regulatory and organizational expectations. References such as Appendix E to Part 236 for rail systems, EPRI’s T&D control center course, and Aufait UX’s description of ISO 9241‑110 dialogue principles help frame safety‑critical information design. Teams practice designing clear, redundant alarms, robust degraded‑mode indications, and error‑resistant control layouts, and they learn how to evaluate HMIs with operators through simulations, walkthroughs, and field tests.

Finally, real‑time performance and optimization training, guided by Crank Software’s recommendations, ensures that engineers can balance responsiveness with constrained embedded resources. They learn how to profile HMI performance, adjust rendering strategies, manage memory, use real‑time operating systems, and verify performance on real hardware under load.

When your team has progressed through these stages, continuous improvement becomes more natural. Engineers know how to apply incremental design changes, as EPRI suggests for control room HMIs, rather than waiting for major system overhauls. They can assess their own interfaces using tools and communities mentioned in the LinkedIn skill‑building framework and refine them release after release.

FAQ

How fast should a power system HMI respond to user input?

Crank Software notes that automotive HMIs aim to respond within about 100 milliseconds to maintain perceived responsiveness and support safety. While exact targets for UPS and power protection HMIs depend on the underlying controls and communications, using a similar order of magnitude as a design goal is reasonable. Training should emphasize prompt visual feedback for every operator action and careful measurement of actual response times on real hardware.

Which standards and references are most relevant for safety‑critical HMIs?

Aufait UX highlights ISO 9241‑110 for human‑system interaction dialogue principles, including guidelines for control sizing, dialog structure, and navigation efficiency. Appendix E to Part 236 of US rail regulations provides design expectations for safety‑critical HMIs, including clear prioritization of safety information and error‑resistant controls. Training courses from EPRI for transmission and distribution control centers and from Tonex for general HMI design further translate these principles into practical patterns for industrial control environments.

Do power engineers need formal UX training, or can they learn HMI design on the job?

Articles from Amulet Technologies and Keba argue that engineers face a strategic choice. They can either invest significant time in mastering UX principles themselves or collaborate with dedicated UX professionals. In practice, even a modest amount of structured UX training, combined with partnerships with UX specialists on complex projects, raises the quality of power HMIs dramatically. Programs like RealPars’ high‑performance HMI courses, Siemens’ HMI design workbook, and human‑factors‑oriented courses such as Tonex’s provide concrete starting points.

Well‑designed HMIs will not fix a weak one‑line diagram or an undersized UPS, but they reliably make strong systems easier to operate safely. When you train your team in both user‑centered design and embedded performance, your UPS, inverter, and protection HMIs become assets rather than liabilities in every disturbance, test, and transfer.

References

1. https://www.nist.gov/document/navid-misaghian-surf-presentation
2. https://niccs.cisa.gov/training/catalog/tonex/human-machine-interface-hmi-safety-principles
3. https://ww2.jacksonms.gov/Resources/4UhMhB/272014/HighPerformanceHmiHandbook.pdf
4. https://reclaim.cdh.ucla.edu/_pdfs/scholarship/FQjrSS/Books%20The%20High%20Performance%20Hmi%20Handbook%20Second%20Edition.pdf
5. https://www.ecfr.gov/current/title-49/subtitle-B/chapter-II/part-236/appendix-Appendix%20E%20to%20Part%20236
6. https://blog.cranksoftware.com/real-time-performance-optimization-in-hmi-design-development-for-embedded-systems
7. https://www.solisplc.com/hmi-programming-guide
8. https://www.amulettechnologies.com/unlocking-superior-hmi-design-simple-strategies-to-elevate-your-hmi-game/
9. https://www.eleken.co/blog-posts/human-machine-interface-design
10. https://www.realpars.com/courses/hmi-design-best-practices