South African Class 7E3, Series 1

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South African Class 7E3, Series 1 - Wikipedia

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South African Class 7E3, Series 1

No. E7216 at Pyramid South, Pretoria, 14 May 2013

Type and origin
Power type	Electric
Designer	Hitachi
Builder	Dorbyl
Model	Hitachi 7E3
Build date	1983-1984
Total produced	60
Rebuilder	Transwerk
Rebuild date	2000-2003
Number rebuilt	16 to Class 7E4

Specifications
Configuration:
• AAR	C-C
• UIC	Co'Co'
• Commonwealth	Co-Co
Gauge	3 ft 6 in (1,067 mm) Cape gauge
Wheel diameter	1,220 mm (48.03 in)
Wheelbase	13,460 mm (44 ft 1+7⁄8 in)
• Bogie	4,060 mm (13 ft 3+7⁄8 in)
Pivot centres	10,200 mm (33 ft 5+5⁄8 in)
Panto shoes	12,075 mm (39 ft 7+3⁄8 in)
Length:
• Over couplers	18,430 mm (60 ft 5+5⁄8 in)
• Over body	17,480 mm (57 ft 4+1⁄4 in)
Width	2,906 mm (9 ft 6+3⁄8 in)
Height:
• Pantograph	4,180 mm (13 ft 8+5⁄8 in)
• Body height	3,941 mm (12 ft 11+1⁄8 in)
Axle load	21,420 kg (47,220 lb)
Adhesive weight	123,500 kg (272,300 lb)
Loco weight	123,500 kg (272,300 lb)
Electric system/s	25 kV AC 50 Hz catenary
Current pickup(s)	Pantographs
Traction motors	Six HS-1054-GR
• Rating 1 hour	525 kW (704 hp)
• Continuous	500 kW (670 hp)
Gear ratio	16:94
Loco brake	Air & Rheostatic
Train brakes	Air & Vacuum
Couplers	AAR knuckle

Performance figures
Maximum speed	100 km/h (62 mph)
Power output:
• 1 hour	3,150 kW (4,220 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
Class	Class 7E3
Number in class	44
Numbers	E7216-E7259
Delivered	1983-1984
First run	1983

The South African Railways Class 7E3, Series 1 of 1983 is an electric locomotive.

Between 1983 and 1984, the South African Railways placed sixty Class 7E3, Series 1 electric locomotives with a Co-Co wheel arrangement in mainline service. Beginning in 2001, sixteen of these dual cab locomotives were rebuilt to single cab locomotives and reclassified to Class 7E4.^[1]^[2]^[3]

Manufacturer

The 25 kV AC Class 7E3, Series 1 electric locomotive was designed for the South African Railways (SAR) by Hitachi and built in South Africa by Dorbyl, who also supplied the mechanical components. Sixty locomotives were delivered by Dorbyl in 1983 and 1984, numbered in the range from E7216 to E7275.^[1]^[4]

Like Union Carriage and Wagon (UCW), Dorbyl did not allocate builder’s numbers to the locomotives it built for the SAR, but used the SAR unit numbers for their record keeping.^[1]

Features

Appearance

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 no. 1 end. Series 1 and Series 2 locomotives are visually indistinguishable from each other, but the two sides of both series are sufficiently different in appearance that a pair of them coupled at the same ends appears at first glance to be two different locomotive types. The roof access ladder side is smooth, while the other side has several large grilles.^[1]

Pantographs

The locomotive's pantograph placement is unusual in not being equidistant from the locomotive ends. The contact shoe centre of the no. 1 end pantograph is 6,155 millimetres (20 feet 2.3 inches) from the longitudinal centre of the locomotive, while that of the no. 2 end pantograph is 5,920 millimetres (19 feet 5.1 inches) from the longitudinal centre.^[1]

Brakes

On the Class 7E3, Series 1, control of traction and rheostatic braking is by stepless solid-state electronics. The electrical equipment was designed for high power factor operation, obtained by the switching in of power-factor correction capacitors.^[4]

Unlike the Classes 7E and 7E2 Series 1 and 2 where thyristors are used, these locomotives use silicon-diode rectifiers.^[5]

Bogies

To reduce flange and rail wear, the bogies of the Class 7E3 have a shorter wheelbase than the Class 7E1, 4,060 millimetres (13 feet 3.8 inches) instead of 4,400 millimetres (14 feet 5.2 inches).^[1]^[4]

Like the Class 7E1, the Class 7E3 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.^[4]

Reclassifications

In the period from the early 1990s until 2007, various modifications to improve downhill braking capacity were done to the Coalink line’s Hitachi-designed locomotives. The first set of upgrades were done on the fifty Class 7E1 locomotives.^[2]

Class 7E4

From 2001, seventeen Class 7E3 locomotives, sixteen Series 1, numbers E7260 to E7275, and one Series 2, no. E7276, underwent significant modifications. This included the installation of Hitachi micro-processor controls with improved rheostatic brakes, auxiliary inverters designed and built by Fuji, and the conversion from double cab to single cab since the no. 2 end cab space was required for some of the new equipment. These modified single-cab locomotives were reclassified to Class 7E4.^[2]^[3]

Class 7E5

The conversions to Class 7E4 were costly, however, and it was decided to modify further Class 7E3 locomotives to a lesser extent, gaining almost the same benefits at a lower cost since they remained as double cab locomotives. In total about fifty locomotives of both series were upgraded in this manner. These were reclassified to Class 7E5, although externally they were still identical to the Class 7E3.^[2]

Class 7E6

Following some systems failures on the upgraded Class 7E5 locomotives, a further variation in the modifications was applied to the remaining Class 7E3 locomotives which had not yet been upgraded. These units were then reclassified to Class 7E6. Eventually all the Class 7E5 locomotives were also modified once again to meet the Class 7E6 specifications.^[2]

Revert to Class 7E3

By October 2007 all these locomotives were fully upgraded and standardised in respect of their rheostat flat topping and EPROM software. Since, apart from the single cab Class 7E4 conversions, they were once again all identical, those which had been reclassified to Classes 7E5 and 7E6 reverted to their original Class 7E3 classifications. Although numbers E7216 to E7259 are all officially designated Class 7E3, Series 1 once again, many of these 44 locomotives still bore markings for several years to identify them as either Class 7E5 or Class 7E6. The single cab locomotives remained classified as Class 7E4.^[2]^[3]

Service

Since 1978, 25 kV AC was introduced on all new mainline electrification projects bar one, the exception being the Orex iron ore line from Sishen to Saldanha where 50 kV AC is used. The Class 7E3, Series 1 locomotives all served on the 25 kV AC Coalink line from Ermelo via Vryheid to the Richards Bay Coal Terminal. They remained there until sufficient numbers of the new Class 19E were available by about 2011 to allow some of the Class 7E3 to be re-allocated to Pyramid South, north of Pretoria.^[2]^[4]

Liveries

All the Class 7E3, Series 1 locomotives were delivered in the SAR red oxide livery with signal red buffer beams and cowcatchers, yellow whiskers and with the number plates on the sides mounted on three-stripe yellow wings. In the 1990s some of them were repainted in the Spoornet orange livery with a yellow and blue chevron pattern on the buffer beams and cowcatchers. In the late 1990s many were repainted in the Spoornet blue livery with either solid or outline numbers on the long hood sides.^[6]

Illustration

No. E7229 in Spoornet orange livery at Vryheid, 16 August 2007
No. E7223 in Spoornet orange livery at Pyramid South, 11 March 2017
No. E7238 in blue with outline numbers at Vryheid, 15 August 2007

References

Wikimedia Commons has media related to South African Class 7E3, Series 1.

^ ^a ^b ^c ^d ^e ^f 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
^ ^a ^b ^c ^d ^e ^f ^g 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, 61.
^ ^a ^b ^c Information received from several Transnet employees
^ ^a ^b ^c ^d ^e Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 129–131. ISBN 0869772112.
^ Jane's Train Recognition Guide
^ Soul of A Railway, System 7, Western Transvaal, based in Johannesburg, Part 9. South-Eastwards as far as Volksrust (2nd part) by Les Pivnic. Caption 4. (Accessed on 11 April 2017)

Locomotives of South Africa

Steam

7' ¼" gauge	East London 0-4-0VB Table Bay 0-4-0ST Table Bay 0-4-0T Table Bay 0-4-0WT
Standard 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
Cape gauge Tank engines	CGR 0-4-0ST 1873 CGR 0-4-0ST 1874 CGR 0-4-0ST 1881 CGR 0-4-0ST 1881 Coffee Pot CGR 0-6-0ST CGR 0-6-0T 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 CGR 1st Class 4-4-0T CGR 2nd Class 4-4-0T CGR 3rd Class 2-6-0T CGR Railmotor CSAR Class C CSAR Class E CSAR Rack 4-6-4RT CSAR Railmotor Durban's Congella Durban's Edward Innes Durban's John Milne Durban's Sir Albert Port Elizabeth 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 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 Railmotor SAR Dock 0-4-0ST SAR Dock 0-4-0T SWA 2-8-0T
Cape gauge Tender engines	CGR 1st Class 2-6-0 1876 BP 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 CGR 1st Class 4-4-0TT CGR 2nd Class 2-6-2TT 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 1882 Joy CGR 4th Class 4-6-0TT 1884 CGR 5th Class 4-6-0 1890 CGR 5th Class 4-6-0 1891 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 1st SAR Class 14C 2nd SAR Class 14C 3rd SAR Class 14C 4th 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 1928 SAR Class 16DA 1930 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 SAR Katanga SWA 2-8-0
Cape 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 John King & Miner Cape Copper Britannia Cape Copper Caledonia Cape Copper Clara Cape Copper Condenser Cape Copper Scotia Namaqua Copper Pioneer Walvis Bay 2-4-2T Hope
2' & 600mm gauges	ACR Class NG-G16A CGR NG 0-4-0T CGR NG 0-6-0T CGR NG 4-6-2T CGR Type A 2-6-4T CGR Type C 0-4-0T NGR Class N 4-6-2T SAR Dutton SAR NG 0-4-0T 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 SWA Class Ha SWA Class Hb SWA Class Hc SWA Class Hd SWA Jung SWA Zwillinge

Electric

Amcoal Class E38

Gas-electric

SAR Gas-electric

Diesel

Cape 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 TFR Class 35-800 SAR Class 36-000 SAR Class 36-200 SAR Class 37-000 Spoornet Class 39-000 TFR Class 39-200 TFR Class 43-000 TFR Class 44-000 TFR Class 45-000
2' gauge Diesel–electric	SAR Class 91-000
Cape gauge Diesel–hydraulic	SAR Class 61-000
Cape gauge Electro-diesel	Spoornet Class 38-000

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