Single Pair Ethernet

Single Pair Ethernet Consistent device communication from the sensor to the cloud

Single Pair Ethernet (SPE) enables the transmission of Ethernet via a single wire pair, ensuring a cost-effective and space-saving connection of sensors. Consistent IP-based communication down to the field level becomes possible. In addition to data transmission, Single Pair Ethernet technology also allows the simultaneous power supply of end devices via PoDL - Power over Data Line.

Single Pair Ethernet meets the requirements on a uniform network infrastructure, which is the basis for Industry 4.0 and the Industrial Internet of Things (IIoT).

What exactly is Single Pair Ethernet?

The classic Ethernet, which already connects all upper levels in the automation pyramid, is often unsuitable for connecting the lowest field level. The installation is often too complex or the maximum distances are not sufficient. SPE technology decisively extends the performance profile of the classic Ethernet at this point.

Single Pair Ethernet is another form of the physical layer. Where previously two double wires were required for the transmission of Fast Ethernet (100 Mbps) or four double wires for Gigabit Ethernet, Single Pair Ethernet allows data transmission with just a single wire pair (single pair). This opens up new opportunities for connecting compact devices, sensors, and actuators directly from the field level. Additional subsystems or gateways are no longer required to realize this. SPE is therefore the lightweight and material-saving Ethernet enhancement for many current and future applications.

Man with a tablet during IP-based communication

Consistent IP-based communication from the field level to the cloud

Future-proof network infrastructure with Ethernet-based communication

When directly compared to existing solutions, Ethernet with TCP/IP and Time-Sensitive Networking (TSN) allow real-time capable data transmission with significantly higher data transfer rates. With Single Pair Ethernet, this is also possible with data from the field level. The state-of-the-art transmission technology ensures space- and cost-efficient Ethernet communication from the sensor to the cloud. Large-scale SPE use in a wide range of applications is made possible with the universal compatibility through defined standards for transmission protocols, cabling and device components.

Data transmission via a single double wire allows continued use of existing two-wire cable infrastructures (cable sharing). In particular, this saves greatly on the use of material, while reducing the amount of cabling required, and ensures easy integration. The technology can be used across applications with ranges of up to 1000 meters, high data rates of up to 10 Gbps, and powers of up to 50 W. An SPE network can be set up with a star or line topology. The technology meets the requirements on future-proof network infrastructure.

Free webinar
A compact guide to Single Pair Ethernet
Everything you need to know about Single Pair Ethernet: In the webinar, Phoenix Contact SPE specialists Verena Neuhaus and Tim Kindermann present the technology and discuss trends in industrial communication. They also show you how you can use SPE products profitably in your applications.
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Webinar on Single Pair Ethernet with Phoenix Contact SPE specialists Verena Neuhaus and Tim Kindermann

Single Pair Ethernet technology features

Single Pair Ethernet standards

Different standards and norms regulate everything around SPE technology, from Ethernet interfaces, through cabling, to data transmission. The SPE standards are defined in IEEE 802.3. This standard describes the technical framework for Ethernet-based data transmission via one wire pair. The differences are in transmission rates and distances. IEC 63171 describes the compatible connectors for these SPE standards.

Phoenix Contact provides IP20 connectors in accordance with IEC 63171-2 as well as IP67 connectors in an M8 and M12 design in accordance with IEC 63171-5. In addition, SPE M12 hybrid connectors in accordance with IEC 63171-7 are currently being developed. The SPE cables are defined in standard IEC 61156-1x. It is also possible for existing cable infrastructures to be used if they meet the requirements.

SPE standards

Transmission paths

Single Pair Ethernet originates from the automotive industry. The goal is to realize an efficient and uniform infrastructure that can deliver high performance with as little cabling as possible. Similar requirements apply to applications in other industries. However, in numerous applications, the 100 meters as the maximum connection length for classic Ethernet are simply not sufficient. The SPE standard 10BASE-T1L in accordance with IEEE 802.3cg provides for a significantly longer transmission distance. This standard defines data cabling with a single wire pair and a transmission distance of up to 1000 meters.

With a transmission length of 1000 meters, the transmission rates reach up to 10 Mbps or 1 Gbps with a transmission length of 40 meters. These transmission rates are sufficient even for the most sophisticated sensor components from the field level. This means that SPE interfaces can be used universally for industrial applications.

PoDL – Power over Data Line

With Power over Data Line (PoDL), sensors and field devices are simultaneously supplied with power

PoDL – Power over Data Line

In addition to data transmission via Ethernet, SPE technology also enables the simultaneous power supply of end devices. With Power over Data Line (PoDL), an effective output of up to 50 W can be transmitted.

The various performance classes are described in the IEEE 802.3bu and IEEE 802.3cg standards. With this technology, it is possible to supply power to a sensor or actuator up to 1,000 meters away with the cable used for data transmission. This minimizes the installation effort and space required for field cabling.

PoDL performance classes

Table with overview of PoDL performance classes
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SPE Evaluation Kit now available
Realize Ethernet-based multidrop applications in accordance with the IEEE 802.3cg standard. The test board is equipped with one USB interface and two SPE interfaces. It supports the bus topology defined in the 10BASE-T1S standard. Communication takes place at data transmission rates of up to 10 Mbps and with up to 50 devices – at a length of 25 m. We will be happy to advise you on this.
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Evaluation Kit for Single Pair Ethernet

Single Pair Ethernet applications SPE is ideal for various applications in Industry 4.0, building, factory, and process automation. SPE technology can be integrated easily into an existing Ethernet infrastructure, regardless of the environment in which it is used. In terms of the trend of resource-conserving, miniaturized devices, Single Pair Ethernet offers more space for your electronics due to the space-saving cables.

Automotive industry
Man in front of a screen in the manufacturing industry
Process industry
Building with building automation from outside
Automotive industry

This space-saving technology is perfect for applications in the automotive industry. With transmission rates from 10 Mbps to 1 Gbps over just one twisted wire pair and a maximum cable length of 15 meters (unshielded) or 40 meters (shielded), it is ideally designed for use in vehicle cable harnesses. In addition, there are a number of new SPE standards under development that are expected to make data transfer rates up to 10 Gbps and even higher possible. In new generations of vehicles, SPE will therefore replace CAN, MOST, FlexRay, and other bus systems. Safety functions, control, and communications run uniformly via Ethernet. This is an essential prerequisite for connected or autonomous driving.

Man in front of a screen in the manufacturing industry

The integration of sensors plays a key role in all manufacturing areas. SPE reliably integrates sensors, actuators, and field devices into an existing Ethernet environment. This means that the necessary data and process information can be transmitted directly to the control level or to a cloud for analysis. As opposed to fieldbus protocols, Ethernet can be used in every level of automation. There is no need for additional gateways or interfaces. The reduction to a single wire pair also simplifies the cabling of sensors directly in machines or systems. The construction, operation, and maintenance of systems become more efficient and cost-effective.

Process industry

Ethernet APL enables the direct two-wire Ethernet connection of field devices and sensors in the ex zones of processing applications. Advanced Physical Layer (APL) uses the 10BASE-T1-L standard of the IEEE 802.3cg along with the IEC TS 60079-47, 2021-03 (2-WISE) standard (2-WISE = 2-Wire Intrinsically Safe Ethernet), and supports explosion protection methods including intrinsic safety. Use in potentially explosive areas is possible, as is the bridging of large distances up to 1000 meters at 10 Mbps. The new communication infrastructure ensures consistent Ethernet use in the process industry.

More about Ethernet APL
Building with building automation from outside

Networked buildings ensure high efficiency, increased security, and additional convenience functions. By using an end-to-end IP protocol, sensors, switches, and thermostats, for example, can be connected to the building management system via the local data network and the cloud.  The consistent SPE cabling replaces existing fieldbus systems, complex interfaces, and gateways. There is also the option to reuse existing two-wire cable infrastructures such as network cables. This makes installation and commissioning significantly easier.

Find out more about building automation

Our products

M8, M12, M12 Hybrid, and IP 20 SPE connectors

SPE connectors

Compact device and cable connectors from the ONEPAIR series for Single Pair Ethernet are ideal for efficient data transmission in factory and process automation as well as building cabling.

The pin connector patterns in accordance with IEC 63171-5 with an M8 and M12 design have become established for industrial applications, even in harsh field environments. The IP20 pin connector pattern in accordance with IEC 63171-2 is leading the way in building cabling. This pin connector pattern is the most compact of the entire series of standards and enables a doubling of the packing density compared to the conventional RJ45 interface. The reduced cabling is the basis for future-proof Ethernet communication.

SPE PCB terminal blocks are particularly suitable for Industry 4.0 and IIoT applications

SPE PCB terminal blocks

Single Pair Ethernet represents a powerful technology for Industry 4.0 and IIoT applications. This is where the PCB terminal blocks in the COMBICON range come into their own, due to their clear color coding and intuitive handling.

Managed SPE switch

Managed SPE switches

The managed SPE switches enable modern sensors and field devices with an SPE interface to be connected directly to the Ethernet network for the first time. They thus provide the basis for an intelligent SPE solution in which sensor data from the field level is integrated into the cloud and the Internet.

With the 10BASE-T1L SPE standard, the managed switch even supports distances of up to 1,000 meters. The sensors are also optimally supplied with power by means of Power over Data Line (PoDL).

Phoenix Contact SPE consulting team: Tim Kindermann, Verena Neuhaus, and Guadalupe Chalas

What our consulting team for Single Pair Ethernet offers

Phoenix Contact has the expertise and the product portfolio to use Single Pair Ethernet in different industries and areas. Find out how SPE experts Verena Neuhaus, Guadalupe Chalas, and Tim Kindermann will work with you to develop customized solutions for Single Pair Ethernet, the key technology of digitalization.

Your key partner for smart networking

Phoenix Contact is your key partner for the integration of Single Pair Ethernet. From the device interface, the cabling, and active network components; from sensors in the field to the PC in your office. As the pioneer in the field of digitalization, Phoenix Contact is developing a comprehensive product portfolio.

Single Pair Ethernet System Alliance logo, an alliance of leading technology companies

The Single Pair Ethernet System Alliance

Phoenix Contact has come together with other leading technology companies to form the SPE System Alliance. The partner companies are bundling their Single Pair Ethernet expertise and ensuring the target-oriented exchange of this knowledge, and thus pursuing the common goal of promoting SPE technology for the Industrial Internet of Things (IIoT) and all other areas of application.

Single Pair Ethernet questions and answers

M8 and IP20 connectors for Single Pair Ethernet
Factory automation topology with Single Pair Ethernet
SPE standards and their features
Single Pair Ethernet used in an embedded system
Cable infrastructure for SPE
M8 and IP20 connectors for Single Pair Ethernet

The Ethernet technology already available today provides transmission speeds of up to 10 Gbps over just one wire pair for your application.

Factory automation topology with Single Pair Ethernet

With SPE infrastructure, you can reduce data cabling and avoid media breakdowns from the field to the cloud as well as device failures. You can establish networks with a consistent Ethernet-based structure so that gateways are no longer needed. Plus, cabling with SPE is easier and more time saving, because only two wires have to be connected. The 10Base-T1L standard enables Ethernet cabling with ranges of up to 1000 m.

SPE standards and their features

SPE standards are defined in IEEE 802.3. Currently, there are five different standards with different transmission speeds and distances that have already been exceeded. Further standards are in discussion.

Single Pair Ethernet used in an embedded system

Yes, a power of up to 50 W can be transmitted via the PoDL (Power over Data Line) standard. The various performance classes are described in the IEEE 802.3bu and IEEE 802.3cg standards.

Cable infrastructure for SPE

It is conceivable that you could use existing cable infrastructures for SPE if they meet the requirements. SPE cables are defined in standard IEC 61156-1x.

Other new communication technologies Consistent communication through to the field

New communication standards such as OPC UA, TSN, SPE, and 5G are currently being created by various committees and in standardization projects. However, these new technologies should not be considered independent of each other – rather, they will form the communication of the future together.
As a technology leader with more than 30 years of experience in industrial communication technology, Phoenix Contact is actively involved in all of the key standardization committees. In these committees, we are helping to shape the new, cross-manufacturer communication standard for automation.

Find out more about the new standards on our webpages.