The introduction of the steam engine at the end of the 18th century, electrified mass production 100 years later, computer-aided automation since the 1970s and now Industry 4.0: all industrial revolutions have revolutionized the way we work and manufacture and multiplied productivity. At the same time, they have opened up new 'raw materials' - steam power, electricity, the processing power of computers and, with Industry 4.0, data as the 'raw material' of the 21st century. As a result, the physical world is merging with the digital world, while at the same time networking is increasing, with every machine and every 'thing' exchanging information with others.

This change on the factory floor has an impact on connectivity technologies. Because when everyone is communicating with everyone else, the number of connections is exploding and the demands on their quality and availability are also increasing. However, this does not necessarily mean that the data transmission rate will also increase. According to the motto "a lot helps a lot", users often buy cables that are oversized.

Downsizing the cables

One example: While Ethernet cables with 10 Gbit/s can be useful for high-speed cameras for quality control, this maximum data transfer rate is not necessary for every sensor. Downsizing Ethernet data lines is therefore a trend that is likely to move into factories over the next few years.

The 'Epic MH' connector system from Lapp can be flexibly equipped for cables with a wide range of functions and can accommodate any number of connector modules for power, signals and data.

© Lapp

Instead of four pairs of wires, so-called single-pair Ethernet cables only have one pair of wires. For many applications, 1 Gbit/s is fast enough. Single-pair data cables require less space and are cheaper to purchase. These cables can be a noticeable relief, especially in machines with many sensors where space is at a premium. Another positive effect is that such slimmed-down cables can be longer. There is a length limit of 100 m for connections with Ethernet cables. Interference increases over longer distances, which can result in data errors. However, current developments in semiconductor chips from the automotive industry mean that many of these faults can now be corrected - allowing ranges of up to 1 km to be achieved.

The future speaks Ethernet

Industrial Ethernet is currently growing at 22% per year, while fieldbus systems are only growing at 6%. In 2018, the number of Industrial Ethernet systems installed in factories will exceed that of fieldbuses for the first time. Concepts such as Single Pair Ethernet are also benefiting from this. Cables for Single Pair Ethernet are not yet available - at least not for use in industry. The automotive industry is already using similar cables in vehicles, but there are still no standards for industrial applications. Working groups within the well-known user organizations, ODVA for Ethernet/IP or PI for Profinet, are already working on these. Lapp, for example, is expected to produce the first series products for Single Pair Ethernet in two to three years. The necessary hardware chips can be adapted from the automotive industry. The cable structure is very simple and only requires adaptation to the environmental conditions in an industrial environment. Initial designs for connectors are also available to ensure the connection of the modified cable.

The hybrid approach

There is currently another trend that, at first glance, seems to contradict downsizing: the increasing demand for hybrid cables. The aim here is not to accommodate as few cores as possible in one sheath, but on the contrary to pack as many cables as possible into one sheath. Such hybrid cables - also known as single-cable solutions - combine different functions in one cable. As a rule, these are connection cables for servo drives plus feedback cables for querying sensors. Lapp offers such hybrid cables, for example, for the 'Hiperface DSL' motor feedback system from Sick or for Acurolink from Hengstler. As single-cable solutions save a lot of space compared to several separate cables with separate connectors, they also deserve the label 'downsizing'.

From downsizing to wireless?

When it comes to saving space in cabling, switching to wireless technologies is an obvious choice. The market for wireless technologies in factory networking is currently growing at 32% per year, albeit still at a low level - wireless technologies currently have a market share of 6%. WLAN, Bluetooth or mobile radio have advantages where flexibility is important - for example when connecting sensors in large systems such as in the chemical industry or for mobile applications. In terms of range, robust data connection, energy efficiency and, in particular, the delay in information transmission (latency), however, wired technologies still score highly. In addition, cables are less susceptible to malicious interference or hacker attacks. This is not expected to change with new standards such as 5G. Wireless is not a threat to wired systems, but rather a supplement for special requirements.

Author:
Guido Ege is Head of Product Management and Product Development at U.I. Lapp in Stuttgart.