Data networks in trains can now be implemented reliably and in a future-proof manner using the preLink system and EtherRail cables, which are specially designed for railway requirements. With Ethernet delivered via one pair of wires, rail operators can reduce their operating costs and optimise production. These products have been developed to meet the demands of train travellers, who now expect high performance internet access during their journey.
Railway operators must therefore offer an appropriate data infrastructure to meet these requirements. This requires new cabling systems, which HARTING has developed to ensure reliable and fast internet in trains.
The central component of the preLink system is the termination block, which allows the cable connection to be performed quickly, simply and reliably. The miniaturised size of the preLink contact block makes it possible to prefabricate data cables separately from the train car before installation. A minimum hole diameter of just 12mm is enough to insert and route the cables.
Once the cables have been laid, the appropriate connector is attached, depending on the network device to be connected. Both RJ45 and M12 D- and X-coded connectors (socket or pin) are available for data transmission of up to 10Gbit/s. This unique range of mating faces, in conjunction with standardised preLink connection technology, offers unparalleled flexibility and investment security, especially over long periods of use within railway scenarios. The system simultaneously simplifies assembly, making it both faster and more reliable.
A further innovation allows M12 sockets to be connected via preLink. The newly designed sockets can be used both as a loose cable coupling, as well as a housing feedthrough, whilst a preLink printed circuit board socket allows the user to connect pre-assembled preLink cables directly to the printed circuit board without the need for detours.
As a result, there is no need for a permanent connection to a housing, meaning Ethernet connections can be quickly and cheaply brought directly to the circuit board. The combination of the modular preLink system and Etherrail cable is the suitable solution for cabling rolling stock. With easy-to-install connectors and cables, trains can be equipped with future-ready Gigabit Ethernet, making an important contribution towards delivering the infrastructure required for the mobile workplace of the future.
Ethernet through Single Twisted Pair (SPE)
The goal of Ethernet via Single Twisted Pair cable and small connectors according to IEC 63171-3 is to achieve weight savings while offering identical performance. Under IEEE 802.3bp (1000 BASE-T1), cable lengths up to 40m can transmit 1Gbit/s while the cable length is about one-third less than conventional 8-wire Ethernet cable.
A standard Ethernet cable with four wire pairs for 1/10Gbit/s Ethernet weighs about 45kg per kilometre. In contrast, a Single Pair cable with the same bandwidth weighs only 30kg per kilometre. Since several kilometres of cable are installed in the cars of passenger trains alone, this offers considerable savings in terms of vehicle weight.
Tool-less installation with PushPull
HARTING offers its PushPull solutions to simplify assembly and service in the railway sector while improving reliability. The solutions consist of the circular M12 PushPull connector in a rugged metal housing, as well as the lightweight, easy-to-use rectangular variant 4 connector. Securely transmitting power, data and signals up to Category 6A presents no difficulties with M12 and variant 4.
The advantage of PushPull connectors lies in the tool-free installation, regardless of whether circular or rectangular versions are used. The connectors are simply gripped and attached. The connectors produce an audible 'click' indicating that they have been securely locked and correctly mated, saving up to 75% of installation time.
Both connectors feature robust IP protection class 67 and are tested in accordance with fire protection standard EN 45545-2. Not only does PushPull offer time savings, its compact design and tool-free installation means it’s easier to fit in space-restricted areas such as roof cavities, underfloor areas and control cabinets.
The HARTING Technology Group has focussed on the rail sector for years, and the company’s extensive portfolio of products and solutions will be on show at Railtex at the NEC, Birmingham, from 13th-16th May. Visit Stand E65 (next to the Seminar Theatre) to find out more.