Single Pair Ethernet (SPE) – a leap forward in technology

Single Pair Ethernet (SPE) – a leap forward in technology

Every so often we experience a leap forward in technology. We are now seeing one of those very moments. Recently, several manufacturers working together have introduced a new Ethernet connection. Single Pair Ethernet, or SPE, is the use of two copper wires that can transmit data at speeds of up to 1 Gb/s over short distances while simultaneously delivering Power over Dataline (PoDl). This could be a major step forward in factory automation, building automation, the rise of smart cars, and railways. Speed in data acquisition and transmission is essential to all industries. Whether we look at the expansion of sensor networks in factories and plants or building autonomous vehicles, massive amounts of data are being collected. The ability to acquire and transmit that data reliably is needed now more than ever.

The SPE Industrial Partner Network has come together to create a new universal standard in communication via Ethernet, IEC 63171-6. HARTING, Würth Electronics and others have established an ecosystem of communication protocols, cabling, connectors, and devices to support the new technology.

(Image source: HARTING)

How it works. Standard Ethernet works using multiple pairs of copper wire to transmit data. To transmit 100 Mb/s of data, two pairs were required, for 1 Gb/s, four pairs are required. This means cables must be larger with larger connections and devices. With the magnitude of the number of sensors throughout the manufacturing process, the amount of cabling required also increases dramatically. That is expensive and requires vast amounts of valuable space. Transmitting those large amounts of data through smaller pathways is now needed. SPE can transmit at speeds of 1 Gb/s across distances of up to 40 meters as well as offer PoDl.

Where does it make sense to employ SPE? Each application requires different solutions. Transitioning to SPE from standard Ethernet may not always make good sense. In some situations, the transition may even be cost prohibitive, especially when considering the number of interfaces and devices that would need to be changed over. Large factories, for example, may be too large to implement SPE. It may however, make sense in applications where weight is an important factor along with the speed of transmission for large amounts of data. Think automotive and railway applications. In automotive applications, smart cars will be able to take advantage of SPE, allowing them to do things like park themselves, detect lane changes, and engage in automated emergency braking.

The implementation of SPE into building automation is another potential market. With many companies moving toward “Smart” technologies to make their buildings more energy efficient, the incorporation of sensors are required. Lighting sensors, temperature sensors, occupancy sensors, and humidity sensors, to name a few, are required for building automation. While many of these sensors can be wireless and require little bandwidth, they do still require power. Four pair Ethernet is of course capable of handling the load. Using single pair Ethernet however, means the amount of cabling required is significantly reduced. The combination of sensors and IoT connected devices for a single building can number into the hundreds, even thousands. This makes the need for smaller cabling even greater. Incorporating SPE into building automation can potentially save companies significant financial investment all while enabling them to process large amounts of data quickly.

Digi-Key has recently begun adding single pair Ethernet products for T1 Industrial Single Pair Ethernet Connector and Würth Electronics to our product portfolio. Please visit our new SPE landing page for more information regarding product details and specifications.

About this author

Image of Eric Halvorson

Eric Halvorson, Partnership Marketing Manager – Strategic Programs, has been with Digi-Key for over 12 years. Eric’s focus is in the Industrial Automation Market. He graduated from Northland Community and Technical College in 2011 with an AAS degree in Electronics Technology and Automated Systems. Until recently, Eric worked as a Product Manager in Electromechanical with a primary focus in Switches. Eric enjoys spending his free time woodworking, fixing things, and time out on the range.

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