South African Class 6E1, Series 8

Builder's plate

These dual cab locomotives had a roof access ladder on one side only, just to the right of the cab access door. The roof access ladder end was marked as the no. 2 end. A corridor along the centre of the locomotive connected the cabs which were identical apart from the fact that the handbrake was located in cab 2. A pantograph hook stick was stowed in a tube mounted below the lower edge of the locomotive body on the roof access ladder side. The locomotive had one square and two rectangular access panels along the lower half of the body on the roof access ladder side and only one square access panel on the opposite side.[1]

Hatch door R

Hatch door L

The Class 6E1 was produced in eleven series over a period of nearly sixteen years. While some of the Class 6E1 series are visually indistinguishable from their predecessors or successors, some externally visible changes did occur over the years.[1]

Series 8 was the only Class 6E1 series with unique visual distinguishing features. It could be distinguished from all earlier series by its large hatch door on each side, below the second small window to the right of the side door on the roof access ladder side and below the first window immediately to the right of the side door on the other side. It could also be distinguished from all subsequent series by the absence of rainwater drainage holes along the lower body sides.[1]

The Class 5E, 5E1, 6E and 6E1 locomotives were notoriously difficult to enter from ground level since their lever-style door handles were at waist level when standing inside the cab. This made it impossible to open the door from outside without first climbing up high enough to reach the door handle while hanging on to the side handrails with one hand only. Crews therefore often choose to leave the doors ajar when parking and exiting the locomotives.[3]

Series 8 and some late model Series 7 locomotives were equipped with doors on which the outside door latch handle was mounted near floor level with a simple drawer pull type handle at mid-door level.[4]

During 1990 and 1991, Spoornet semi-permanently coupled several pairs of otherwise largely unmodified Class 6E1 locomotives, reclassified them to Class 16E and allocated a single locomotive number to each pair, with the individual units in the pairs inscribed "A" or "B". The aim was to accomplish savings on cab maintenance by coupling the units at their no. 1 ends, abandoning the no. 1 end cabs in terms of maintenance and using only the no. 2 end cabs. Most were later either disbanded with the units reverting to Class 6E1 and regaining their original numbers or getting rebuilt to Class 18E.[5]

Ten known Series 8 locomotives were part of such Class 16E pairs.[5]

• E1914 and E1915 became 16-503 A and B.
• E1916 and E1917 became 16-501 A and B.
• E1918 and E1919 became 16-505 A and B.
• E1925 and E1926 became 16-504 A and B.
• E1928 and E1929 became 16-506 A and B.

No. E1913 as Class 17E, Capital Park, Pretoria, 28 September 2006

Class 17E locomotives were modified and reclassified from Class 6E1 Series 7, 8 or 9 locomotives during 1993 and 1994. Key modifications included improved regenerative braking and wheel-slip control to improve their reliability on the steep gradients and curves of the Natal mainline. Unlike the unmodified but reclassified Class 16E locomotives, the Class 17Es retained their original unit numbers after reclassification.[5]

A stumbling block was that the regeneration equipment at many of the sub-stations along the route was unreliable. Since there was no guarantee that another train would be in the same section to absorb the regenerated energy, there was always the risk that line voltage could exceed 4.1 kV, which would make either the sub-station or the locomotive trip out. As a result, the subsequently rebuilt Class 18E locomotives were not equipped with regenerative braking.[6]

Fifty-five known Series 8 locomotives were modified and reclassified to Class 17E. Their unit numbers are listed in the table.[5]

Cab 1 of Class 18E no. 18-204, ex Class 6E1 no. E1972, Capital Park, Pretoria, 16 May 2013

Beginning in 2000, Spoornet began a project to rebuild Series 2 to 11 Class 6E1 locomotives to Class 18E, Series 1 and Series 2 at the Transnet Rail Engineering workshops at Koedoespoort. In the process the cab at the no. 1 end was stripped of all controls and the driver's front and side windows were blanked off to have a toilet installed, thereby forfeiting the locomotive's bi-directional ability.[5][6]

Brake rack in Class 18E no. 18-089

Since the driving cab's noise level had to be below 85 decibels, cab 2 was selected as the Class 18E driving cab primarily based on its lower noise level compared to cab 1, which was closer and more exposed to the compressor's noise and vibration. Another factor was the closer proximity of cab 2 to the low voltage switch panel. The fact that the handbrake was located in cab 2 was not a deciding factor, but was considered an additional benefit.[6]

While the earlier Class 6E1, Series 2 to 7 locomotives had been built with a brake system which consisted of various valves connected to each other with pipes and commonly referred to as a "bicycle frame" brake system, the Class 6E1, Series 8 to 11 locomotives were built with an air equipment frame brake system, commonly referred to as a brake rack. Since the design of the rebuilt Class 18E locomotives included the same brake rack, the rebuilding project was begun with the newer series 8 to 11 locomotives to reduce the overall cost of rebuilding. [6]

Bar two, all the Class 6E1, Series 8 locomotives which were used in this rebuilding project were rebuilt to Class 18E, Series 1 locomotives. The known numbers and renumbering details are listed in the table.[6]