Joe Biondo, senior program manager—OEM, Rockwell Automation: Decentralized drives contain the drive itself, plus the incoming power disconnect circuitry, field I/O, low-voltage power supply and other connectivity in one package (Figure 1). They can be placed closer to the motor or directly on the machine, rather than in a control cabinet. This shift allows OEMs to mount automation components and create a modular, on-machine design that avoids or reduces the need for long motor, low-voltage power and I/O cables.

Compared to centralized systems, decentralized drives can ease installation because they reduce cabinet space, long-run wiring and troubleshooting points. Unplanned downtime can also be reduced. Decentralized drives are available with predictive maintenance capabilities to predict the life of components and schedule their replacement before they fail. The drives can also include features like automatic device configuration for faster replacement and recovery. Overall, the connectorized nature of the decentralized drive allows them to be maintained by operators, instead of electricians.

For OEMs, this can offer significant business benefits. Recent Rockwell Automation research indicates the average downtime event is now 40 hours and costs an average of $3.6 million. Every additional hour incurs a cost of $92,000. Leading OEMs are embracing decentralized drives to not just reduce wiring, but enable faster deployment and avoid this costly downtime.

What are some applications where decentralized drives might benefit an industrial system being designed and built?

Joe Biondo, senior program manager—OEM, Rockwell Automation: Decentralized drives are especially valuable in environments where space constraints or rapid installations are important. Among the most common examples are packaging lines, material handling and machine skids where sections need to be replicated quickly without redesigning a large cabinet space each time. For these segments, OEMs want simplified machines with a lower footprint. Decentralized drives lower the time to build a machine, as mounting traditional drives in panels requires specialized expertise, as well as additional “ring out” and test time. Decentralized drives are manufactured as a complete unit, lowering risk of miswiring and driving up overall machine build quality.

Another key application is among OEMs designing machines that will be deployed globally and customized repeatedly. Decentralized designs can make machine sections easier to standardize and quickly replicate, shortening lead times. Per the Rockwell research, leading OEMs treat lead time as a critical performance driver, not merely a back-end metric. This ability to scale and deliver quickly is a major competitive advantage.

Servo motors have traditionally been preferred for high-precision, high-response applications. How might an inverter affect someone's evaluation of switching out servos for induction motors?

Joe Biondo, senior program manager—OEM, Rockwell Automation: Servo systems offer precision and responsiveness, which is why they’ve long been the default option for high-performance motion applications.

However, modern VFDs, or inverter-based drives, deliver increasingly precise speed, torque and motor control. This is enabling induction motors to take on a greater range of applications than they could in the past. Today’s VFDs can also provide real-time operational data and system-level visibility. This helps machine engineers better understand and optimize machine performance. Some drives include an encoder input offering a type of closed-loop control. While not as precise as a servo, this can be “just enough” control for the application.

The bottom line: For applications that don’t require the highest levels of dynamic response, pairing a modern VFD with an induction motor can deliver performance needs as well as cost savings, greater simplicity and easier scalability.

How have frequency inverters evolved over recent generations in terms of control features, communication protocols and energy efficiency?

Joe Biondo, senior program manager—OEM, Rockwell Automation: In addition to providing high-performance motor control for demanding applications, modern VFDs use innovative technology to impact operations in a few key ways.

First, they can boost productivity. For example, they can use adaptive control to adjust to machine operating characteristics that change over time. This helps reduce mechanical wear and keeps a machine running optimally.

They can also help reduce unplanned downtime. Using predictive analytics, modern VFDs can notify operators of issues like blown fuses, rising temperatures and components nearing their end of life that can compromise drive or motor health. Maintenance teams can then address the issue before it escalates into a downtime event.

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Modern VFDs can also reduce energy usage. They do this using a variety of energy-saving features, such as the ability to be placed in a low-energy state when a process isn’t running or automatically adjust output voltage based on the applied load. VFDs with active front-end technology can also have a regenerative capability to put energy onto the incoming power supply.

Finally, modern VFDs can include safety I/O, which streamlines the machine design by putting safety I/O where it’s needed.

What sorts of emerging technologies, such as edge computing, AI-assisted diagnostics or advanced simulation are being integrated into drives and inverters?

Joe Biondo, senior program manager—OEM, Rockwell Automation: Drives are no longer simply executing commands, they’re increasingly becoming intelligent assets that can sense, communicate and support predictive decision-making. These capabilities are seen first-hand in edge computing and advanced analytics.

Edge computing is crucial in industrial environments where split-second decisions are made. Data from controllers and sensors is generated almost instantly, but sending it to the cloud for processing can introduce delays. By running AI at the edge where it’s closer to the machine, manufacturers can act on that data in real time, enabling faster, more reliable responses when timing is critical.

AI-assisted analytics and predictive analytics are becoming increasingly common in modern drives. For example, AI-powered analytics software can monitor drives and notify production personnel of operating anomalies to help avoid unplanned downtime. Drives with predictive analytics also can calculate when certain drive components will fail so maintenance teams can plan to replace them at an appropriate time.

Speaking of advanced simulation, the definition of a digital twin can vary, based primarily on the application. What's your definition, and how are digital twins utilized within the development and commissioning processes, and what impact have digital twins had on reducing project lead times or improving reliability?

Joe Biondo, senior program manager—OEM, Rockwell Automation: A digital twin is a dynamic virtual replica of a physical asset. It’s dynamic in that it continues learning and changing in response to stimuli in a simulated environment.

Digital twins can be used from design to commissioning and beyond, and they can be highly impactful.

At the earliest stages, digital twins can help guide design decisions for a single machine or an entire plant. New deployments can be simulated, evaluated and optimized before parts are ordered, eliminating the need for costly physical prototypes and finding fixes to production issues before they ever happen. In some cases, manufacturers have used virtual testing and validation to identify and resolve dozens of bottlenecks before launch.

Digital twins can also be used to commission assets virtually, allowing teams to identify design issues earlier and avoid last-minute changes that can lead to delays and cost overruns. Virtual commissioning involves using a digital twin to test PLC code logic and other system elements virtually rather than waiting until a machine is on the shop floor. Using virtual commissioning, companies have reduced commissioning and startup time from 4-6 weeks to just 6 days.

In addition, another benefit of a digital twin is being able to demonstrate new machine design functionality to potential customers, instead of enduring the expense of building prototypes. This allows the mechanical design team to develop multiple iterations of a given design before ever building the physical mechanisms, a big savings of engineering, parts procurement and build time.

Today, building digital twins is becoming a less manual and time-intensive process thanks to AI. Teams can now generate digital-twin models using natural-language prompts and LLMs, saving hours or even days when building digital twins.

What kinds of data and sensor inputs are most valuable for building accurate digital twins of drive systems, and how important is it to ensure real-time synchronization between physical and virtual models?

Joe Biondo, senior program manager—OEM, Rockwell Automation: The most useful data is anything that shows how the machine is performing, compared to what it’s supposed to be doing. For a drive system, that includes basics like speed, temperature, power usage, vibration and how the motor is performing over time. It’s also important to capture things like commands and settings, which are telling the machine what to do, defining how it moves through its processes and impacting how it interacts with other equipment.

Real-time synchronization is important, but it often relies heavily on the purpose of the digital twin. If the digital twin is being used for virtual commissioning, a very accurate simulation is more useful than one that’s live, but not as realistic. For operational twins that support functions like monitoring or decision-making, tighter synchronization becomes much more important.

OEMs should match the twin to the question they are looking to answer. Not every twin needs live synchronization to be valuable, but every useful twin does need trustworthy data. The better the data foundation, the more value that can be extracted for all use cases of the digital twin.