Another Interface Standard? Yes, But IIoT-Focused IEC 63171-7 Isn’t What You Think

By Chad Cox

Production Editor

Embedded Computing Design

December 06, 2021


Another Interface Standard? Yes, But IIoT-Focused IEC 63171-7 Isn’t What You Think
Image Courtesy of TE Connectivity

The industrial automation and manufacturing sectors use an unfathomable number of interface types, communication protocols, and power delivery mediums simply to turn on and move data between machines. While each was optimized for a specific purpose, on a larger scale this differentiation turns from an advantage to an impediment.

For proof, just follow the hardware-Look at the number of bridges, switches, port adapters on sale from any automation hardware distributor whose sole purpose is to translate information from one system’s protocol to another’s or deliver power to range of different equipment.

Of course, all of this could be simplified with the use of standardized interfaces. And boy haven’t we tried, from M8, M12, and M23 to DB-9s and RJ45s to terminal blocks and BS 4343 (IEC 60309) connectors and many, many more. Indeed, like the popular xkcd comic, the desire for standardization has often exacerbated the problem.

Image Credit: xkcd 

Nevertheless, the problem remains. It’s still expensive, time-consuming, and restricting from an engineering perspective. But now that Industrial Ethernet infrastructure has become even more pervasive thanks to IT/OT convergence and the Internet of Things, it may be time to give standardization another look.

M12 Delivers Data and Power on a Single Twisted Pair

Currently members of the Single-Pair Ethernet (SPE) System Alliance’s Industrial Partner Network are advocating the popular M12 hybrid interface connector for inclusion in the new IEC 63171-7 standard. They expect the connector to deliver exactly what you’d expect from the hybrid connector: transmit Ethernet data and power across a single industrial interface. 

Image Credit: TE Connectivity

TE Connectivity first publicly demonstrated a hybrid SPE system for simultaneous Ethernet data and power supply through an M12 connector in July of this year. So while M12 connectors are nothing new, they’re now being promoted as a unified solution that “creates broad industry consensus on a power-and-data hybrid format that easily integrates machines into a network and improves power distribution.”

Image Credit: TE Conectivity

The SPE Industrial Partner Network envisions the M12 hybrid connector defined in IEC 63171-7 as a substitute for common fieldbus and analog components, as it combines the SPE data connection with four power contacts plus functional earth. According to TE, it can replace these components by providing: 

  • High-speed IP-based communication up to 1 Gbps/600MHz per cable
  • Improved flexibility of up to 11 kW/16A per cable for power distribution across the network without the need for point-to-point connections
  • Lower complexity and cost through use of a single twisted pair and cable versus two or four pairs and multiple wires
  • Reduced electromagnetic interference (EMI) thanks to separate data and power contacts
  • Increased data and power supply ranges
  • Long-term support from multiple vendors

New Standards for Existing Tech

Clearly, the hope is that standardizing around an IEC 63171-7 interface will simplify the integration of systems that need to communicate individual sensor’s data to the cloud and back. These include high-power use cases like small three-phase drives and DC servo drives used in all manner of manufacturing applications.

In other words, IEC 63171-7 technology already exists, is easy to connect to existing Ethernet infrastructure, and was developed for the Industrial IoT.

“Manufacturers often struggle to realize the advantages of IIoT because their networks can’t communicate from the cloud all the way down to an individual sensor on a machine,” explains Eric Leijtens, Managing Director for TE Connectivity. “This is why the new ‘-7’ standard is so critical. It helps us overcome that gap in data at the network edge by creating an industry-standard approach for connecting to physical assets in a production environment.”

Although it was first technically demonstrated as an SPE solution just a few months ago, M12 connectors are everywhere in the market and have been for some time. For that reason, in part, more than 80 companies and multiple trade groups are supporting the IEC 63171-7 standard.

We already have enough wheels. Let’s all use one we already have.

For more on SPE technology, visit the TE Connectivity website for white papers, brochures, and more.

For more information on the SPE standardization effort, visit the Single-Pair Ethernet Systems Alliance website at

Chad Cox. Production Editor, Embedded Computing Design, has responsibilities that include handling the news cycle, newsletters, social media, and advertising. Chad graduated from the University of Cincinnati with a B.A. in Cultural and Analytical Literature.

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