Industrial Automation

Making Single Pair Ethernet in Factory Automation a Reality

Chen Zhang

When it comes to Single Pair Ethernet (SPE) in factory automation, it may seem as if SPE isn’t moving as quickly as many thought it would. Despite numerous discussions within the Single Pair Ethernet (SPE) Consortium and among industrial organizations, it’s getting a slow start in plant environments.

In recent blogs, we discussed how the industry is overcoming hurdles to Single Pair Ethernet deployment, as well as the advantages of replacing a four-wire line with a two-wire line so SPE can confidently be used in practice.

Now it’s time to talk about where SPE is today. What needs to happen within the ecosystem so this technology can quickly find its way into factory automation environments?



The Market Needs to Mature

Consider the birth of the electric vehicle (EV) for a moment. Traditionally, evolution in factory automation is driven by large automotive companies that boast predictable high volumes, a drive for economies of scale and scope, and a dedication to quality.

As EVs enter the scene, however, many of these large manufacturers have lost their historical momentum. Their processes, workflows, facilities and technology are set up to support internal combustion engine (ICE) vehicles, not EVs. Naturally, reigniting growth in EVs will take these automakers a while. To gain efficiency and maintain business portability and market competitiveness in the meantime, some U.S. automakers are subcontracting EV engine manufacturing to Japanese companies.

In other words, the business model for EVs isn’t mature yet. Supply chain interfaces and product standards aren’t finalized, either, which drives business model divergence instead of convergence.

As a result, Tesla has been able to capture value in terms of EV manufacturing and come out years ahead, securing battery resources to build up charging infrastructures. Why? How? Because it started as an EV manufacturer but also recognized the gap that existed within the ecosystem and, as a result, reconfigured the value chain to close it. This puts the company in a unique position to explore its role in the new value chain (a blue ocean strategy in an ecosystem era that creates differentiation and low costs to create new market space and demand).

We’re seeing this scenario play out in the world of SPE, too. Companies that have to make big pivots to incorporate new technology are naturally slower to adapt to it. The inevitable transformation involved with accepting new technology can be a painful—but necessary—journey, and it impacts almost every stakeholder in the chain.

For industrial environments, adopting the SPE interface usually means a new PHY, new magnetics and new connectors and cables—perhaps in addition to new firmware and new application software as well.

Everyone Needs to Stop Waiting on Everyone Else

It takes more than interest in SPE to bring the technology to the mainstream in factory automation. The SPE ecosystem relies on many players who all have to work together to bring Single Pair Ethernet to factory automation applications.

Consider a conveyor company, for example. It is difficult to pinpoint a single company that owns every component required to make up a conveyor system: switches, high-speed cameras, motor drive rollers, etc. Separate manufacturers produce each one of those components, while a systems integrator or machine builder then puts the components together. All of these partners must work together to create these systems.

The same holds true for SPE. All industry players need to sort out their position in the new SPE era and understand that the technology relies on more than their products—it relies on collaboration and interaction within the SPE ecosystem. The challenge, though, is that incentives are not equally distributed among different ecosystem partners, which can impact their capabilities and lengthen the learning curve and transformation.

For example, as device manufacturers continue to adopt and integrate new SPE technology, hardware and software for next-generation SPE products will be developed. Manufacturers of end devices need to build new PCB hardware to integrate new ICs to modulate signals. Connector companies need to agree on new standards to maximize compatibility.

Several companies are still learning and under transformation as they prepare for the future, which can make collaboration and interaction more difficult. And, in many cases, the pandemic did not help accelerate the collaboration between companies. If anything, it may have slowed it down. Virtual ad-hoc meetings and cancellations of events and exhibitions had a definite impact on the SPE ecosystem over the last couple of years.

Bringing SPE to Market

Belden is helping the industry bring Single Pair Ethernet to market so plants can benefit from the automation benefits it has to offer.


Our Single Pair Ethernet portfolio of cabling and connectivity products is designed to optimize Ethernet connections in industrial and transportation operations. Belden is also developing solutions to help maximize SPE deployment, introducing SPE to active devices for managed and unmanaged switches.


As Industry 4.0 evolves, and the number of sensors and actuators connected to the factory backbone increases, Single Pair Ethernet is a simple solution that will enhance industrial automation. The question isn’t “if” it will happen, but “when.” Like the Diffusion of Innovation Theory dictates, we are just at the very beginning of the SPE adoption curve. Belden plays as an innovator role, along with other SPE partners who have introduced SPE to the market. Over time, SPE will continue to gain momentum and spread through our industry – the tipping point for the market may be only 3-5 years away. As we learn more, we’ll continue to keep you updated.