South African Class 7E
Encyclopedia
In 1978 and 1979 the South African Railways placed one hundred Class 7E electric locomotives with a Co-Co wheel arrangement in main line service. They were the first 25 kV AC locomotives to see service on South African rails.

Manufacturer

The Class 7E 25 kV AC electric locomotive was designed for the South African Railways (SAR) by the 50 c/s Group, consisting of ACEC
SA Ateliers de Constructions Electriques de Charleroi
SA Ateliers de Constructions Electriques de Charleroi was a manufacturer of a wide range of electrical products and latterly manufactured the electrical parts for Belgian locomotives and multiple units constructed by BN.-History:...

 of Belgium, AEG-Telefunken and Siemens
Siemens
Siemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...

 of Germany, Alsthom-Atlantique and Société MTE of France, and Brown Boveri of Switzerland. They were built by Union Carriage and Wagon (UCW) in Nigel, Transvaal, who was the sub-contractor for mechanical components and assembly.

One hundred Class 7E locomotives were delivered in 1978 and 1979, numbered E7001 to E7100. Beginning with the Class 7E, the SAR numbering practice was changed to make the class number a part of the locomotive’s running number. From the Class 1E up to the last of the Class 6E1 series of locomotives, all electric locomotives were numbered sequentially from number E1 up.

UCW did not allocate builder’s numbers to the locomotives it built for the SAR. While the practice by most other locomotive builders was to allocate builder’s numbers or works numbers to record the locomotives built by them, UCW simply used the SAR running numbers for their record keeping.

Features

On the Class 7E control of traction and rheostatic braking is by stepless solid-state electronics. The electrical equipment was designed for high power factor operation, obtained by a sector control method.

Orientation

These dual cab locomotives have a roof access ladder on one side only, just to the right of the cab access door. The roof access ladder end is marked as the number 2 end. Judging from early photographs of Class 7E locomotives, the distinctive "eyebrow" rainwater beadings above the cab windscreens were added post-delivery.

Service

The Class 7E was designed primarily for goods train service on South Africa’s 25 kV 50 Hz AC electrified lines. Until 1978 all electrified routes in South Africa used 3 kV DC, but from that year all new main line electrification projects bar one used 25 kV AC, the one exception being the 50 kV AC Sishen
Sishen
Sishen is a town in Northern Cape, South Africa. It is the location of a large iron ore mine.- Transport :The mine is connected to the port of Saldanha Bay‎ by the Sishen-Saldanha Railway Line. The line is electrified at 50 kV AC and the trains using this line are amongst the heaviest trains in the...

-Saldanha
Saldanha Bay
Saldanha Bay is a natural harbour on the south-western coast of South Africa, north west of Cape Town. The town that developed on the northern shore of the bay, also called Saldanha, was incorporated with five other towns into the Saldanha Bay Local Municipality in 2000. The current population of...

 line. There are four isolated 25 kV routes.
  • From Pyramid South to Pietersburg and via Rustenburg to Thabazimbi.
  • From Ermelo to the Richards Bay Coal Terminal
    Richards Bay Coal Terminal
    The Richards Bay Coal Terminal , located in the Richards Bay harbour, is the largest coal export facility in Africa. The Chinese port of Qinhuangdao maintains the largest coal exporting terminal in the world, at 209 Million tons compared to Richards Bay with 91 Million tons.Potential throughput is...

     at Richards Bay.
  • From Port Elizabeth to De Aar and from there north to Kimberley
    Kimberley, Northern Cape
    Kimberley is a city in South Africa, and the capital of the Northern Cape. It is located near the confluence of the Vaal and Orange Rivers. The town has considerable historical significance due its diamond mining past and siege during the Second Boer War...

     and south to Beaufort West
    Beaufort West
    Beaufort West is a town in the Western Cape province in South Africa. It is the largest town in the arid Great Karoo region, and forms part of the Beaufort West Local Municipality, with 37 000 inhabitants in 2001....

    .
  • From East London to Springfontein.


When it was electrified, the well known double line "race track" between Kimberley and De Aar was single lined and the section was signalled for single-track centralised traffic control
Centralized traffic control
Centralized traffic control is a form of railway signalling that originated in North America and centralizes train routing decisions that were previously carried out by local signal operators or the train crews themselves. The system consists of a centralized train dispatcher's office that...

 (CTC) with long crossing loops. The second set of tracks were left in place, but unelectrified and isolated from the electrified track. However, in anticipation of increased ore traffic to the Eastern Cape from the Sishen branch north-west of Kimberley, work on wiring the second track was to commence in July 2008.

The Class 7E was placed in service on the coal line from Ermelo to Richards Bay. When later model 25 kV locomotives were introduced, a few Class 7E locomotives went to the Pyramid South and East London lines, but the majority were transferred to the Cape Midlands system to work goods and passenger traffic from Kimberley via De Aar to either Port Elizabeth or Beaufort West. Here the Class 7E finally replaced South Africa’s last big Class 25NC
South African Class 25NC 4-8-4
Between 1953 and 1955 the South African Railways placed fifty Class 25NC steam locomotives with a 4-8-4 wheel arrangement in service. The Class 25NC is the non condensing version of the Class 25 condensing locomotive, of which ninety were placed in service at the same time...

 steam locomotives.

Regional co-operation

A 30c postage stamp depicting a pair of Class 7E locomotives hauling an ore train was one of a set of four commemorative postage stamps that were issued by the South African Post Office on 15 February 1990. The theme illustrated interdependence and regional co-operation in Southern Africa and, in this case, the integrated railway systems that stretched from Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

 in the south to as far north as Dar es Salaam in Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...

. The artwork and stamp design was by the noted stamp designer and artist A.H. Barrett.

Liveries

In the SAR and Spoornet eras, when the official liveries were Gulf Red and yellow whiskers for the SAR, and initially orange and later maroon for Spoornet, many selected electric locomotives and some diesel-electrics were painted blue for use with the Blue Train
Blue Train (South Africa)
The Blue Train travels an approximately journey in South Africa between Pretoria and Cape Town. It is one of the most luxurious train journeys in the world...

, but without altering the layout of the various paint schemes. Blue Train locomotives were therefore blue with yellow whiskers in the SAR era, blue with the Spoornet logo and "SPOORNET" in Spoornet’s orange era, and blue with the Spoornet logo but without "SPOORNET" in Spoornet’s maroon era. In Spoornet’s blue era there was no need for a separate Blue Train livery, while in the Transnet Freight Rail (TFR) era the Blue Train was relegated to the very bottom of the railway’s business priority list.

When the section from Kimberley to Beaufort West was electrified, six Class 7E locomotives, numbers E7004 to E7009, were painted blue with yellow whiskers for use with the Blue Train on that section.

The main picture shows E7067 in Spoornet orange livery.


See also

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