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I will be the first to admit that connectors are far from the most glamourous component in the industrial market. Regularly eclipsed by the latest semiconductor or LED, connectors are the poor country cousins of the electronics world.

Despite this, I maintain that connectors are amongst the most complex component that any engineer must select. The sheer variety of sizes and designs means that the connector market is a minefield that needs to be navigated through rather than a destination to relish. This is also reflected in the time and cost taken when developing a new connector.

It is rare that a brand-new connector is developed from scratch. Rather than revolutionary steps, most new connector products are an evolution of an existing design. This is due to a combination of factors, including the cost of creating an all-new product and the customer’s natural reluctance to use an untried connector. Even in the most forward-looking sectors of the electronics industry, you will often find engineers relying on tried and trusted connectors from previous generations.

The connector industry does not sit on its laurels, however. There are always new products being created and new solutions offered. But it is rare that these new products are destined to make huge waves beyond the connector industry.

The Next Big Thing

The last of these big events was the introduction of the latest USB connector, the USB type-C. Launched 20 years after the original letter-box-shaped USB connector, there is a good chance that the USB-C will become one of the most widely used connectors in history. After a slow start in which it was only fitted to high-end consumer devices, the USB-C is now everywhere. It has become a hugely popular interface connector for non-Apple smartphones, and it can be found on games consoles and computing equipment the world over.

It is worth bearing in mind the steps that were taken behind the scenes before the USB-C was launched into the world. The standard which governs the connector was finalised in 2014, several years before the product started to hit the shelves. In that time, the manufacturers worked to set up their production line to create the new connector, and even then the adoption rate was initially slow. As they say, it takes a long time to become an overnight success.

Image showing a USB connector, saying there's nothing stopping me now

This is a connector that conforms to a single standard to fulfil a clearly defined need. It is smaller than the original USB-A, has been optimised to deliver power and video along with data, and is omnidirectional (how many times have you tried to plug a USB connector in the wrong way round?) Governed by a group of interested parties called the USB Implementers Forum (USB-IF), the final form of the USB-C was agreed upon by some of the driving forces within electronics today including Microsoft, Intel, Compaq. With these big names behind it, is there any doubt that the USB-C will succeed?

There is another new connector on the market. The Single Pair Ethernet (SPE) connector has been created for the smart factory and is designed to take the Ethernet network to the factory floor. The smart factory integrates all elements of the manufacturing environment into a single network, allowing every aspect of the business to be controlled centrally. This means that the smart factory can respond quickly to new demands and reconfigure its activities accordingly.

One of the biggest challenges of the smart factory has been how to integrate the lowest level of automation equipment – the machinery that actually makes the factory what it is – into the network. While all of the office equipment within the smart factory uses conventional computer networking protocols, the sensors, drives and controls that are the muscles of the factory do not. This means that, in between the factory floor and the back office, there needs to be an additional layer of communications equipment to allow all of the elements to talk to each other.

Single Pair Ethernet

This was the problem that SPE was designed to solve. Rather than replace the existing infrastructure entirely, the idea is that small, single-pair cables can branch out to the individual machines, connecting them directly into the ethernet network. This does away with the need for additional layers of communication and integrates everything into one network. Every device that is connected, from the largest server to the smallest sensor, will be part of the whole.

Image showing HARTING Single Pair Ethernet Connectors

HARTING Single Pair Ethernet Connectors

There is something curious about the introduction of SPE, however. There is not a single, standardised connector type. Instead, two competing consortia are each promoting their own design. Both consortia include connector manufacturers, alongside companies that are responsible for other parts of the infrastructure – cable, semiconductor, and sensors. The first is the SPE Industrial Partner Network which has standardized on the HARTING T1 connector (203-9055) . Designed as a cable-mounted plug sealed to IP20, the T1 also is available as an insert for the familiar M12 circular connector to provide a sealed, IP67 solution.

The other contender is the SPE System Alliance, which has created a different connector, as shown by Phoenix Contact. Both connectors are small and rectangular connectors with two contacts. However, while both groups are working with the International Electrotechnical Commission to create the IEC 63171 standard, the two connectors are not compatible with each other.

Phoenix Contact Single Pair Ethernet Connectors

Phoenix Contact Single Pair Ethernet Connectors

What does this mean for the customer? The first, and possibly most important question that needs to be answered is whether everybody wants to fully integrate their whole factory into a single network. Using SPE will not simply be a case of removing one set of cabling and replacing it with another. Instead, there is a huge installed base of equipment in factories around the world, and the expense of replacing it would be incredible. In addition, there are other initiatives in the world of factory connectivity. David Hannaby of SICK Sensors wrote an interesting article about the possibilities of IO-Link for sensors, and interestingly this makes use of the existing M-Series connector, something that is familiar to many installation engineers worldwide.

Ready for Battle?

The second question to be answered is whether one of the two consortia will come to dominate the market? With the lack of a single, coherent standard, will there be a final showdown in the spirit of the battle between VHS vs Betamax, or will there be a protracted stand-off akin to Apple vs Android? And while this question remains, will customers be willing to commit to one solution or the other, not knowing whether they are backing the wrong horse?

New connectors are rare things, especially in markets that will see a high volume of sales. The cost of developing a new standard is such that manufacturers need to receive a sufficient return on their investment. It seems odd to me that, by creating two competing standards, their potential share of the revenue that will be generated in the SPE market will be diluted and the customer base might be reluctant to make the leap to the new technology, especially when other alternatives are available.

I am interested to know what you think.

Connector Geek is Dave in real life. After three decades in the industry, Dave still likes talking about connectors almost as much as being a Dad to his two kids. He still loves Lego too. And guitars.
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