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You might have read about the Siemens Class 700 Desiro City trains that are under construction for Thameslink. A total of 1,140 of the vehicles are being built at the Krefeld factory in Germany. These vehicles will form 55 twelve-car units, each capable of carrying 1,754 passengers, and 60 eight-car units. The first of these new trains have already been delivered to the UK through the Channel Tunnel and put into service.

At the same time, Siemens has been designing and developing a new class of train, the Class 707. This is also an electric multiple unit and it is being built by Siemens for South West Trains working in conjunction with Angel Trains, the leasing company involved.

The contract, valued at £210 million, covers 150 vehicles, made up as 30 five-car trains, which are also currently being built at Krefeld. They are designed to carry a much-needed 18,000 additional peak-time passengers into London Waterloo. This undertaking is being linked with a project to accommodate a further 6,000 additional passengers on completion of associated infrastructure improvements.

Construction of the first vehicles began in October 2015, and the first unit was completed in March 2016. Testing is now well underway at Siemens’ excellent testing facility at Wildenrath, which is about a one-hour drive away from their factory in Krefeld.

Test centre

Wildenrath, due to its strategic location, had been an RAF base from 1950 to 1992 during the Cold War. Siemens took it over in 1997 and now boasts that it is one of the most modern and extensive rail test centres in the world.

It is a boast that is hard to disagree with since there is 30km of track that form four interlinking circuits. These range from a 0.4km layout with gradients varying from 40 to 70 per cent, to a 6km circuit that can test at speeds up to 160kph. There are curved tracks, switches and crossings, third-rail power and overhead contact wires alongside power supplies designed for all of the common DC and AC voltages that exist in Europe. The site is also connected to the main line.

Tim Shoveller.
Tim Shoveller.


The Class 700 has the Automatic Train Operation system (ATO), a requirement for Thameslink trains travelling through the centre of London. While the Class 707s do not have ATO, it would only require minor adjustments for it to be fitted. Both classes, however, do have the European Train Control System (ETCS). This is an emerging requirement for all UK trains as part of the Network Rail plan for a digital railway.

Whilst working for South West Trains, the Class 707s will only use the third-rail power supply. However, they have been designed to work under 25kV AC wires as well. So, throughout the testing and commissioning process, the first two trains will be temporarily fitted with all the necessary equipment for overhead line operation, such as power converters and pantograph. This will enable the new train to be approved for both systems so that any additional order can run under wires, or the trains can be reallocated, without needing further testing.

Thameslink (or the Department for Transport which ordered the trains) decided not to include Wi-Fi in the Class 700s, a questionable decision that has now apparently been reversed. Fortunately, Siemens had included the technology framework in the design so, hopefully, the upgrade will not require too much effort. Suffice it to say that South West Trains has included Wi-Fi in its specification for Class 707s.

Reversing the story, Thameslink Class 700s are all fitted with toilets. However, South West Trains has decided not to include toilets in its Class 707 specification given that the longest journey time is less than one hour and their inclusion would reduce the overall capacity of the trains.

The trains will be lighter than existing fleets and more energy efficient. Built-in carbon dioxide sensors will automatically detect when the air conditioning needs to be adjusted in a controlled manner that will cool passengers without them feeling that someone has suddenly opened a window.

A digital process

Each vehicle is built using state-of-the-art technology. There is a virtual 3D room based in the Siemens Krefeld factory which allows designers to discuss often complex amendments and modifications whilst actually visualising their intentions, thus dramatically reducing the time it takes to resolve such problems and knowing that the solution arrived at is the right one.

This software system is fully integrated with both the design offices and with the production team building the vehicles. Once agreed, amendments to drawings are instantaneous across the company and, as the production manager was keen to point out, he can monitor the progress of work down to the fitting of the smallest item. Everything is logged and recorded on this system.

Managing director for South West Trains, Christian Roth, said: “The introduction of the brand new Class 707 Desiro City trains is an absolutely crucial part of our plans to provide the biggest increase in capacity on this network for decades. We are delighted manufacturing is now underway and look forward to welcoming the first units to the UK.”

DG247985. Class 700 bodyshells. Krefeld. Germany. 15.7.16

Expanding Waterloo

In conjunction with the introduction of the new Class 707s, an £800 million improvement programme for South West Trains was unveiled recently.

The plan is for the improvements to take place over the next three years. This includes rebuilding the former Waterloo International Terminal, allowing Platforms 20 to 24 to be brought back into use with modern facilities. Also, the installation of new track and signalling and a new spacious concourse layout near to Platforms 20 to 24 will enhance facilities for the ever-increasing number of passengers using these services.

As well as lengthening Platforms 1-4 at Waterloo to take 10-car trains, the project plan includes longer platforms at 10 further stations to accommodate the proposed longer trains on the Reading line. Additionally, improvements to associated train depots and maintenance facilities are being planned as well as enhancements at Vauxhall station to increase capacity and improve passenger journeys.

The process of building a Class 707 vehicle in Krefeld through to final approval takes about nine months. South West Trains expects and plans for these trains to start arriving in October this year with the expectation that the entire fleet will be operational by the end of 2017. This will then free-up some existing trains on the South West Trains network to increase capacity on other key routes.

For Siemens, the development of the Class 700 Desiro City trains doesn’t end there. A Class 717 is already being designed for Great Northern. So, for the 2,400 employees at Krefeld, there appears to be a Class 700 workstream emerging that will keep them busy for some time – a very reassuring message during this time of uncertainty.

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  1. Most of the Class 707’s will be used on Waterloo-Windsor & Eton Riverside service replacing the Class 458/5’s and Class 450’s to be used on Waterloo-Reading service and some of the Class 707’s would be operated on Waterloo-Guildford and Waterloo-Weybridge semi-fast commuter services with the former Eurostar Terminal platforms to be redeveloped and to be reopened for 10-car trains as South West Trains will become a 10-car railway network and with the cascaded Class 185’s to be moved from TPE for Waterloo-Exeter Central, Yeovil & Salisbury and other routes across the Westcountry operated by SWT.


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