South African Class 7E2, Series 2

No. E7215 at Pyramid South, Pretoria, 6 October 2009

Type and origin
Power type	Electric
Designer	50 ^c/s Group
Builder	Union Carriage and Wagon
Model	50 ^c/s Group 7E2
Build date	1983
Total produced	40

Specifications
AAR wheel arr	C-C
UIC class	Co'Co'
Gauge	3 ft 6 in (1,067 mm) Cape gauge
Wheel diameter	1,220 mm (48.0 in)
Wheelbase	13,460 mm (44 ft 1.9 in)
• Bogie	4,060 mm (13 ft 3.8 in)
Pivot centres	10,200 mm (33 ft 5.6 in)
Panto shoes	10,200 mm (33 ft 5.6 in)
Length:
• Over couplers	18,465 mm (60 ft 7.0 in)
• Body	17,500 mm (57 ft 5.0 in)
Width	2,896 mm (9 ft 6.0 in)
Height:
• Pantograph	4,190 mm (13 ft 9.0 in)
• Body height	3,942 mm (12 ft 11.2 in)
Axle load	21,000 kg (46,000 lb)
Adhesive weight	124,000 kg (273,000 lb)
Loco weight	124,000 kg (273,000 lb)
Power supply	Catenary
Current collection	Pantographs
Traction motors	Six MG-680
• Rating 1 hour	515 kW (691 hp)
• Continuous	500 kW (670 hp)
Gear ratio	20/117
Loco brake	Air & Rheostatic
Train brakes	Air & Vacuum
Couplers	AAR knuckle

Performance figures
Maximum speed	88 km/h (55 mph)
Power output:
• 1 hour	3,090 kW (4,140 hp)
• Continuous	3,000 kW (4,000 hp)
Tractive effort:
• Starting	450 kN (100,000 lbf)
• 1 hour	319 kN (72,000 lbf)
• Continuous	300 kN (67,000 lbf)

Career
Operators	South African Railways Spoornet Transnet Freight Rail PRASA
Class	Class 7E2
Power class	25 kV 50 Hz AC
Number in class	40
Numbers	E7176-E7215
Delivered	1983
First run	1983

The South African Railways Class 7E2, Series 2 of 1983 is an electric locomotive.

In 1983, the South African Railways placed forty Class 7E2, Series 2 electric locomotives with a Co-Co wheel arrangement in mainline service.^[1]

Manufacturer

Builders’ plate, no. E7204

The 25 kV AC Class 7E2, Series 2 electric locomotive was designed for the South African Railways (SAR) by the 50 ^c/s Group, a consortium consisting of ACEC of Belgium, AEG-Telefunken and Siemens of Germany, Alsthom-Atlantique and Société MTE of France, and Brown Boveri of Switzerland.^[2]^[3]

It was built by Union Carriage and Wagon (UCW) in Nigel, Transvaal, who delivered forty locomotives in 1983, numbered in the range from E7176 to E7215. UCW did not allocate builder’s numbers to the locomotives which it built for the SAR, but used the SAR unit numbers for their record keeping.^[1]

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 designated the no. 2 end.^[1]

In visual appearance, the Series 2 locomotives can be distinguished from the Series 1 by the vertical grilles just to the rear of the driver’s window, on both sides on the Series 2 locomotives, absent on Series 1. Both series have a large grille to the right of centre on the side opposite the roof access ladder side, near roof level on Series 1 locomotives and low down near sill level on Series 2. The three grilles in line, just to the rear of the side doors on Series 1 locomotives, were replaced with a single long grille on Series 2 locomotives. Like the Class 7E, some of the Class 7E2, Series 2 locomotives have distinctive "eyebrow" rainwater beadings above their cab windscreens, but these were added post-delivery and were not installed on all the units.^[1]

Features

Brakes

Control of traction and rheostatic braking on the Class 7E2, Series 2 is by stepless solid-state electronics. The electrical equipment was designed for high power factor operation, obtained by a sector control method.^[2] Like the earlier Classes 7E and 7E2, Series 1, these locomotives were equipped with thyristor technology from the 50 ^c/s Group.

Bogies

To reduce flange and rail wear, the bogies of both series of the Class 7E2 have a shorter wheelbase than the Class 7E, 4,060 millimetres (13 feet 3.8 inches) instead of 4,400 millimetres (14 ft 5.2 in).^[1]^[2]

The Class 7E2 was built with sophisticated traction linkages on the bogies. Together with the locomotive's electronic wheel-slip detection system, these traction struts, mounted between the linkages on the bogies and the locomotive body and colloquially referred to as grasshopper legs, ensure the maximum transfer of power to the rails without causing wheel-slip, by reducing the adhesion of the leading bogie and increasing that of the trailing bogie by as much as 15% upon starting.^[2]

Pantographs

As on the Class 7E, the locomotive's pantograph contact shoe centres are directly above the bogie pivot centres. The reason is to reduce the possibility of pantograph hookups on catenary in sharp curves, such as in turnouts, as a result of sideways movement of the pantograph in relation to the overhead wire.^[1]

Service

The Class 7E2, Series 2 was placed in service on the northern 25 kV AC routes, which stretch from Pyramid South, just north of Pretoria, via Warmbad to Pietersburg and via Brits and Rustenburg to Thabazimbi, where they still serve.^[4]

Illustration

The main picture shows no. E7215 in its original SAR Gulf Red and yellow whiskers livery. Other liveries which were applied to Class 7E2, Series 2 locomotives, are illustrated below.

No. E7202 in Spoornet orange livery at Pyramid South, 6 October 2009
No. E7182 in Spoornet maroon at Pyramid North, 6 October 2009
No. E7200 in Spoornet blue with outline numbers at Pyramid South, 6 October 2009

No. E7206 in Transnet Freight Rail livery at Pyramid South, 27 September 2015
No. E7201 in PRASA's Shosholoza Meyl livery at Pyramid South, 7 May 2013

References

1 2 3 4 5 6 South African Railways Index and Diagrams Electric and Diesel Locomotives, 610mm and 1065mm Gauges, Ref LXD 14/1/100/20, 28 January 1975, as amended
1 2 3 4 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 129–131. ISBN 0869772112.
↑ "UCW - Electric locomotives" (PDF). The UCW Partnership. Archived from the original (PDF) on 12 October 2007. Retrieved 30 September 2010.
↑ Middleton, John N. (2002). Railways of Southern Africa Locomotive Guide - 2002 (as amended by Combined Amendment List 4, January 2009) (2nd, Dec 2002 ed.). Herts, England: Beyer-Garratt Publications. pp. 50–51, 61xx–yy.

Wikimedia Commons has media related to South African Class 7E2 Series 2.

Locomotives of South Africa

Steam

7' ¼" gauge	East London Harbour 0-4-0 Table Bay Harbour 0-4-0ST Table Bay Harbour 0-4-0T Table Bay Harbour 0-4-0WT

4' 8½" gauge	Cape 0-4-0T Blackie Cape 0-4-2 Cape 2-4-0T CGR 0-4-0ST Aid Natal 0-4-0ST Durban Natal 0-4-0WT Natal Natal 4-4-0T Perseverance

3' 6" gauge Tank engines	CGR 0-4-0ST 1873 CGR 0-4-0ST 1874 CGR 0-4-0ST 1881 Coffee Pot CGR 0-6-0ST 1902 CGR 0-6-0T 1876 Back-to-Back CGR 2-6-0ST 1900 CGR 2-6-0ST 1902 CGR 1st Class 0-4-0ST 1875 CGR 1st Class 0-4-0ST 1876 CGR 1st Class 2-6-0ST 1876 CGR 1st Class 4-4-0T 1875 CGR 2nd Class 4-4-0T 1882 CGR 3rd Class 2-6-0T CGR Railmotor CSAR Class C CSAR Class E CSAR Rack CSAR Railmotor DSWA Eight-Coupled Tank 2-8-0T Durban's Congella Durban's Edward Innes Durban's John Milne Durban's Sir Albert Port Elizabeth Harbour 0-4-0ST Kowie Railway 0-6-0T Kowie Railway 4-4-0T Metropolitan & Suburban 4-6-2T NGR 2-6-0T Durban & Pietermaritzburg NGR Class I 2-6-2T NGR Class K 0-4-0ST NGR Class K 0-6-0ST NGR Class K 2-6-0T NZASM 10 Tonner NZASM 13 Tonner NZASM 14 Tonner NZASM 18 Tonner NZASM 19 Tonner NZASM 32 Tonner NZASM 40 Tonner PPR 26 Tonner PPR 35 Tonner Portuguese SAR 0-4-0ST 1903 SAR 0-4-0T no. 69 SAR Class A SAR Class B SAR Class C SAR Class C1 SAR Class C2 SAR Class D SAR Class E SAR Class F SAR Class G SAR Class H SAR Class H1 SAR Class H2 SAR Class J SAR Class K SAR Clayton Railmotor

3' 6" gauge Tender engines	CGR 1st Class 2-6-0 1876 Beyer, Peacock CGR 1st Class 2-6-0 1876 Kitson CGR 1st Class 2-6-0 1879 CGR 1st Class 2-6-0 1891 CGR 1st Class 4-4-0 1879 CGR 1st Class 4-4-0TT 1881 CGR 2nd Class 2-6-2TT 1875 CGR 3rd Class 4-4-0 1883 CGR 3rd Class 4-4-0 1884 CGR 3rd Class 4-4-0 1889 CGR 3rd Class 4-4-0 1898 CGR 3rd Class 4-4-0 1901 CGR 3rd Class 4-4-0 1903 CGR 4th Class 4-4-2 CGR 4th Class 4-6-0TT 1880 CGR 4th Class 4-6-0TT 1882 CGR 4th Class 4-6-0TT 1884 CGR 5th Class 4-6-0 1890 CGR 5th Class 4-6-0 1891 DSWA Eight-Coupled Tender 2-8-0 NGR Havelock NGR Class I SAR Class Exp 1 SAR Class Exp 2 SAR Class Exp 3 SAR Class Exp 4 SAR Class Exp 5 SAR Class Exp 6 SAR Class S SAR Class S1 SAR Class S2 SAR Class 1 SAR Class 1A SAR Class 1B SAR Class 2 SAR Class 2C SAR Class 3 SAR Class 3A SAR Class 3B SAR Class 4 SAR Class 4A SAR Class 5 SAR Class 5A SAR Class 5B SAR Class 6 SAR Class 6A SAR Class 6B SAR Class 6C SAR Class 6D SAR Class 6E SAR Class 6F SAR Class 6G SAR Class 6H SAR Class 6J SAR Class 6K SAR Class 6L SAR Class 6Y SAR Class 6Z SAR Class 7 SAR Class 7A SAR Class 7B SAR Class 7C SAR Class 7D SAR Class 7E SAR Class 7F SAR Class 8 SAR Class 8A SAR Class 8B SAR Class 8C SAR Class 8D SAR Class 8E SAR Class 8F SAR Class 8R SAR Class 8X SAR Class 8Y SAR Class 8Z SAR Class 9 SAR Class 10 SAR Class 10A SAR Class 10B SAR Class 10C SAR Class 10D SAR Class 11 SAR Class 12 SAR Class 12A SAR Class 12B SAR Class 13 SAR Class 14 SAR Class 14A SAR Class 14B SAR Class 14C SAR Class 15 SAR Class 15A SAR Class 15B SAR Class 15C SAR Class 15CA SAR Class 15E SAR Class 15F SAR Class 16 SAR Class 16A SAR Class 16B SAR Class 16C SAR Class 16D SAR Class 16DA SAR Class 16E SAR Class 17 SAR Class 18 SAR Class 19 SAR Class 19A SAR Class 19B SAR Class 19C SAR Class 19D SAR Class 20 SAR Class 21 SAR Class 23 SAR Class 24 SAR Class 25 SAR Class 25NC SAR Class 26 Red Devil

3' 6" gauge Articulated engines	CGR Fairlie CGR Kitson-Meyer SAR Class FC SAR Class FD SAR Class GA SAR Class GB SAR Class GC SAR Class GCA SAR Class GD SAR Class GDA SAR Class GE SAR Class GEA SAR Class GF SAR Class GG SAR Class GH SAR Class GK SAR Class GL SAR Class GM SAR Class GMA SAR Class GO SAR Class HF SAR Class KM SAR Class MA SAR Class MB SAR Class MC SAR Class MC1 SAR Class MD SAR Class ME SAR Class MF SAR Class MG SAR Class MH SAR Class MJ SAR Class MJ1 SAR Class U

2' 6" gauge	Cape Copper 0-6-0T 1871 Cape Copper Britannia Cape Copper Caledonia Cape Copper Clara Class Cape Copper Condenser Cape Copper Scotia Class Namaqua Copper Pioneer

2' & 600mm gauges	ACR Class NG-G16A CGR NG 0-6-0T CGR NG 4-6-2T CGR Type A 2-6-4T CGR Type C 0-4-0T DSWA Class Ha DSWA Class Hb DSWA Class Hc DSWA Class Hd DSWA Jung DSWA Zwillinge NGR Class N 4-6-2T SAR NG 0-4-0T 1899 SAR Class NG1 SAR Class NG2 SAR Class NG3 SAR Class NG4 SAR Class NG5 SAR Class NG6 SAR Class NG7 SAR Class NG8 SAR Class NG9 SAR Class NG10 SAR Class NG-G11 SAR Class NG-G12 SAR Class NG-G13 SAR Class NG-G14 SAR Class NG15 SAR Class NG-G16

Electric

Amcoal Class E38

Diesel

3' 6" gauge Diesel-electric	PRASA Class Afro 4000 SAR Class DS SAR Class DS1 SAR Class 31-000 SAR Class 32-000 SAR Class 32-200 SAR Class 33-000 SAR Class 33-200 SAR Class 33-400 SAR Class 34-000 SAR Class 34-200 SAR Class 34-400 SAR Class 34-500 SAR Class 34-600 SAR Class 34-800 SAR Class 34-900 SAR Class 35-000 SAR Class 35-200 SAR Class 35-400 SAR Class 35-600 SAR Class 36-000 SAR Class 36-200 SAR Class 37-000 Spoornet Class 39-000 TFR Class 35-800 TFR Class 39-200 TFR Class 43-000 TFR Class 44-000

2' gauge Diesel-electric	SAR Class 91-000

3' 6" gauge Diesel-hydraulic	SAR Class 61-000

3' 6" gauge Electro-diesel	Spoornet Class 38-000

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