South African Class ES1

The South African Railways Class ES1 of 1924 was an electric locomotive.

South African Class ES1
Class ES1 shunting locomotive, c. 1930
Type and origin
Power typeElectric
DesignerEnglish Electric
BuilderEnglish Electric
ModelSAR ES1
Build date1924
Specifications
Configuration:
​
 • AARB
 • UICBo
 • CommonwealthBo
Gauge3 ft 6 in (1,067 mm) Cape gauge
Wheel diameter38 in (965 mm)
Wheelbase10 ft 5 in (3,175 mm)
Length:
​
 • Over couplers24 ft 5 in (7,442 mm)
 • Over beams22 ft (6,706 mm)
Height10 ft (3,048 mm)
Axle load12 LT 3 cwt (12,340 kg)
Loco weight24 LT 5 cwt (24,640 kg)
Electric system/s235 V 196 A, 208 cell battery
Current pickup(s)N/A
Traction motorsTwo
Gear ratio5.4:1
CouplersJohnston link-and-pin
AAR knuckle (1930s)
Performance figures
Power output50 hp (37 kW)
Tractive effort:
​
 • 1 hour8,500 lbf (38 kN)
Career
OperatorsSouth African Railways
ESKOM
ClassClass ES1
Number in class1
NumbersE123, renumbered E502
NicknamesQueen Mary
Delivered1924
First run1924
Withdrawn1978

In 1924, the South African Railways placed a single Class ES1 battery-powered shunting locomotive in service at the construction site of the Colenso power station. In 1927, the power station and the locomotive were sold to the Electricity Supply Commission and in 1937 the locomotive was purchased back for use at the Daimana (Danskraal) locomotive depot.[1][2]

Manufacturer

During the electrification of the Glencoe to Pietermaritzburg section of the Natal mainline, a mountainous single-track line which carried heavy mineral traffic towards the port of Durban on an alignment with severe gradients and tight curves, the Colenso power station was built by the South African Railways (SAR) to supply the power for this line.[3]

A single battery-powered electric shunting locomotive, the only battery-powered locomotive to ever see service on the SAR, was purchased from English Electric in 1924 for use at the power station construction site.[1][4]

Characteristics

The centre-cab locomotive had a Bo wheel arrangement, the two axles being driven by two 37 kilowatts (50 horsepower) traction motors, operating at 235 volts and powered by a 208 cell nickel-iron alkali type battery with a 435 amp-hour capacity.[1]

Service

The locomotive remained in service at the Colenso power station after 1927, when the power station and all its equipment, including the battery locomotive, was sold to the Electricity Supply Commission (ESKOM), the state-owned South African national power corporation.[1]

In 1937, the locomotive was purchased back from ESKOM by the SAR, designated Class ES1 with unit number E123 and stationed at the Daimana (Danskraal) locomotive depot at Ladysmith where it was used as shop shunting engine to move cold steam locomotives and dead electric units. Nicknamed Queen Mary, it was later renumbered to E502. It remained in service at Danskraal until it was withdrawn from service in 1978.[1][2]

References
Wikimedia Commons has media related to South African Class ES1.
  1. Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. p. 135. ISBN 0869772112.
  2. Espitalier, T.J.; Day, W.A.J. (1946). The Locomotive in South Africa - A Brief History of Railway Development. Chapter VII - South African Railways (Continued). South African Railways and Harbours Magazine, April 1946. p. 296.
  3. "South African Railways Power Plant". Electric Railway Journal. 60 (24): 914. 9 December 1922. Retrieved 15 September 2010.
  4. South African Railways Index and Diagrams Electric and Diesel Locomotives, 2'0" & 3'6" Gauge, circa 1940, as amended
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.