South African Class 1E
The South African Railways Class 1E of 1925 was an electric locomotive.
Between 1925 and 1945, the South African Railways purchased 172 Class 1E electric locomotives, spread over seven orders. They were the first mainline electric locomotives to be introduced in South Africa.
Railways electrification
In 1920, following a report and recommendations on electric traction by consulting engineers Merz & McLellan of London, the South African Parliament authorised the electrification of the lines between Durban and Pietermaritzburg in Natal and between Cape Town and Simon's Town on the Cape Peninsula at a cost of £4.4 million.At the time, there were two routes between Pietermaritzburg and Durban. The newer route with its 1 in 66 gradients was chosen for electrification over the older route with its 1 in 33 gradients. Between Cato Ridge and Durban, electrification necessitated the doubling of the track and the construction of ten tunnels as well as the construction of long stretches of cutting and embankment across difficult terrain.
After it was pointed out that the Natal traffic bottleneck was really above rather than below Pietermaritzburg, electrification in Natal eventually first took place between that city and Glencoe. It was a mountainous single-track section which carried heavy mineral traffic towards the port of Durban on an alignment with severe gradients and tight curves where the existing working by steam locomotives became too slow and inefficient to keep up with increasing traffic.
Work commenced in 1922 and the first electric train on that section was run in November 1925.The whole section was in full electric operation by January 1927. Electrification of the Simon's Town line commenced in March 1927 and full electric operation was introduced during September 1928. Electrification of the new mainline section from Pietermaritzburg to Durban via Delville Wood was completed in 1936 and the first electrically hauled passenger train entered Durban station on 2 December of that year. Electrification of the original Natal Government Railways mainline from Rossburgh to Cato Ridge was commenced soon after the new mainline was energised, but during the Second World War the work was halted and not restarted until the late 1950s, eventually being switched on in May 1959.
Benefits
An important consideration in deciding upon the economics of electrification was the potential saving in wage-bills. Electrification would reduce the required crew roster from 300 drivers and stokers to 170 drivers and assistants. In addition it was expected that a large reduction in overtime would be accomplished by increasing the average train speeds from steam traction's to electric traction's on the Glencoe to Pietermaritzburg section, with slightly higher future speeds anticipated. It was further estimated that the total capacity of the line would be increased by 60%.Colenso power station
The chosen overhead power supply was, the highest direct current overhead voltage in use at the time. The Colenso power station was built by the SAR specifically to power this line. The complete electrical system for the section consisted of the coal power station at Colenso which generated three-phase current at, stepped up and distributed at to twelve automatic substations along the route. The substations were located at an average of about apart and all but one were supplied at by two separate three-phase transmission lines. The one at Colenso was fed directly from the power station.At the substations, the current was stepped down again to, converted by synchronous motor generators to and fed to the overhead catenary for use by the electric locomotives. The overhead equipment consisted of a copper catenary which supported a copper contact wire by means of droppers. The track structures were steel lattice masts erected on concrete foundations.
Manufacturers
South Africa's first electric locomotive, the Class 1E, entered service in Natal in 1925. The locomotive was designed by Metropolitan-Vickers of Manchester while the mechanical parts of the unit were approved by, Chief Mechanical Engineer of the South African Railways F.R. Collins. At the time, the first batch of 78 Class 1E, Series 1 locomotives constituted the largest order for a single type of electric locomotive to have been placed anywhere in the world. The eventual fleet of 172 locomotives was built for the SAR in seven series by four manufacturers over a period of twenty years.- Series 1. The first sixty locomotives, numbered in the range from E1 to E60, were built by the Swiss Locomotive & Machine Works in 1923 and 1924. The remaining eighteen Series 1 locomotives, numbered in the range from E61 to E78, were built by Metropolitan-Vickers in 1925.
- Series 2. All seventeen locomotives, numbered in the range from E79 to E95, were built by Metropolitan-Vickers in 1925 and 1926 and entered service in 1927. These units were slightly heavier than those of Series 1.
- Series 3. Five locomotives, numbered in the range from E98 to E102, were built by Metropolitan-Vickers in 1936. The skipped numbers E96 and E97 were allocated to Class ES locomotives.
- Series 4. Twenty locomotives, numbered in the range from E103 to E122, were built by Metropolitan-Vickers in 1936.
- Series 5. Twenty-two locomotives, numbered in the range from E139 to E160, were built by SLM in 1938. The skipped numbers in the range from E123 to E138 were allocated to Classes ES1, ES, 2E, DS and DS1 locomotives.
- Series 6. Twenty locomotives, numbered in the range from E161 to E180, were built by the Nederlandsche Fabriek van Werktuigen en Spoorwegmaterieel in 1938.
- Series 7. Ten locomotives, numbered in the range from E181 to E190, were built by Robert Stephenson & Hawthorns in 1944 and entered service in 1945. These units were built under austerity measures during World War II and, on account of wartime transport difficulties, were shipped in a disassembled condition. Body panels, frames and partitions were crated flat, together with bundles of tubing, copper bus-bar, coils of wire and cable, and general electrical equipment. The bogies were shipped partially assembled. The mechanical erection of these units was done by the Mechanical Engineer at the Pietermaritzburg shops after which the units were towed to Danskraal for the assembly of electrical equipment.
Characteristics
Interior layout
The interior layout consisted of five compartments.- The driving cabs at each end contained the control gear, meters, gauges, vacuum brake valves and other equipment and were connected by a side corridor along the right side of the locomotive when looking towards Cab 1.
- The high tension compartment was in the middle of the locomotive and contained the high voltage control switches and resistances, accessed through a sliding door which was both mechanically and electrically interlocked to prevent it being opened while a pantograph was in contact with the overhead catenary.
- A machinery compartment behind each cab housed auxiliary gear such as two motor generator sets, one of and the other of, each coupled to a blower fan on its shaft for ventilating the main motors. In addition it contained a motor-driven rotary vacuum exhauster, air compressor, air reservoirs for the brakes, low-tension control contactors and resistances for the auxiliaries and battery, together with contactor gear for controlling the field of the larger motor generator.
Orientation
These dual cab locomotives had four grilles below the four windows on the equipment side and only two grilles below the centre two windows on the corridor side. When observing the locomotive from the side with four grilles, the no. 1 end would be to the left.Bogies
Like the subsequent Classes 2E, 3E and 4E, the Class 1E had bogie mounted draft gear. It had a Bo+Bo wheel arrangement with an articulated inter-bogie linkage, therefore no train forces were transmitted directly to the locomotive body. The bogie pivot centres were apart. One of the bottom pivot centres was fixed while the other was free to move longitudinally to allow for any wear occurring in the articulated coupling between the two bogies.Three different cowcatchers were used on Class 1E units. The first six series were delivered with cowcatchers made up of horizontal bars. The Series 7 units were delivered with a plain plate type cowcatcher, but the bogies were sometimes interchanged during overhauls with the result that units from different orders often carried cowcatchers not as originally fitted. In later years, units were often fitted with boiler-tube cowcatchers made up of vertically mounted short pieces of boiler tube, similar to those that were fitted on most South African steam locomotives after World War II.