The Spoornet Class 17E of 1993 was a South African electric locomotive.
During 1993 and 1994, Spoornet modified several Class 6E1, Series 7, 8 and 9 locomotives to improve their braking and traction reliability for service on the Natal mainline. These modified locomotives were reclassified to Class 17E.
Manufacturer The 3 kV DC Class 6E1 electric locomotive was built for the South African Railways (SAR) by Union Carriage & Wagon (UCW) in Nigel, Transvaal, with electrical equipment supplied by the General Electric Company (GEC). UCW did not allocate works numbers to the locomotives which it built for the SAR, but used the SAR unit numbers for their record keeping.
Characteristics Bogies
The Class 6E1 was built with sophisticated traction linkages on their 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, ensured 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. This feature was controlled by electronic wheel-slip detection devices and an electric weight transfer relay which reduced the anchor current to the leading bogie by as much as 50A in notches 2 to 16.
Brakes The locomotive itself used air brakes, but it was equipped to operate trains with air or vacuum brakes. While hauling a vacuum braked train, the locomotive's air brake system would be disabled and the train would be controlled by using the train brakes alone to slow down and stop. While hauling an air braked train, on the other hand, the locomotive brakes would engage along with the train brakes. While working either type of train downgrade, the locomotive's regenerative braking system would also work in conjunction with the train brakes.Operation – South African Classes 6E, 6E1, 16E, 17E and 18E
When the locomotive was stopped, the air brakes on both bogies were applied together. The handbrake or parking brake, located in cab no. 2, only operated on the unit's last axle, or no. 7 and 8 wheels.
Orientation 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.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
Modification to Class 17E 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 grades and curves of the KwaZulu-Natal mainline.
A stumbling block was that the regeneration equipment at many of the sub-stations along the route was unreliable and 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.Class 17E braking systems
Unlike the Class 16E locomotives, which were renumbered and reclassified but otherwise unmodified semi-permanently coupled pairs of Class 6E1, Series 3 to Series 9 locomotives that merely had their no. 1 end cabs abandoned in terms of maintenance, the Class 17Es retained their original unit numbers after reclassification, but with a "17E" marking applied below the locomotive's unit number behind the driver's side window.
Apart from the "17E" markings, they were visually indistinguishable from unmodified Class 6E1s. Those in SAR Gulf Red and yellow whiskers livery that still carried number plates even still showed "6E1" on the plates. Altogether 139 Class 6E1 locomotives were modified to Class 17E, of which 14 were Series 7, 55 Series 8 and 70 .
Rebuilding to Class 18E
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 (TRE) 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.Information gathered from the rebuild files of individual locomotives at Transnet Rail Engineering's Koedoespoort shops, or obtained from John Middleton as well as several Transnet employees
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.
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.
Between 2002 and 2007, all but three of the Class 17Es were rebuilt to Class 18E, Series 1. The exceptions are numbers E1778, E1803 and E2035, which are presumed to have been scrapped. The table lists their Class 6E1 series and numbers, Class 18E numbers and year of rebuilding. +Class 17E units rebuilt to Class 18ECount17Eno.6E1seriesYearbuilt18Eno.Yearrebuilt1 E17497 1977 18-3322007 2 E17757 1977 18-2922006 3 E17767 1977 18-3262007 4 E17777 1977 18-2892006 5 E18017 1977–7818-3312007 6 E18057 1977–7818-2602006 7 E18107 1977–7818-2942006 8 E18227 1977–7818-0972003 9 E18267 1977–7818-3442007 10 E18277 1977–7818-2832006 11 E18327 1978 18-3072007 12 E18437 1978 18-2702006 13 E19008 1979 18-2622006 14 E19018 1979 18-2982006 15 E19048 1979 18-0872003 16 E19058 1979 18-3112007 17 E19068 1979 18-2842006 18 E19078 1979 18-3302007 19 E19088 1979 18-2882006 20 E19098 1979 18-0612002 21 E19108 1979 18-2952006 22 E19138 1979 18-3402007 23 E19218 1979–8018-3412007 24 E19228 1979–8018-3062007 25 E19248 1979–8018-3342007 26 E19318 1980 18-2022005 27 E19338 1980 18-3202007 28 E19348 1980 18-0942003 29 E19358 1980 18-0182002 30 E19368 1980 18-2742006 31 E19378 1980 18-2162005 32 E19388 1980 18-2932006 33 E19398 1980 18-2032005 34 E19408 1980 18-0842003 35 E19448 1980 18-1972005 36 E19458 1980 18-2072005 37 E19468 1980 18-0622002 38 E19478 1980 18-2902006 39 E19498 1980 18-0642002 40 E19628 1980 18-0702003 41 E19648 1980 18-3292007 42 E19658 1980 18-3162007 43 E19668 1980 18-1782005 44 E19678 1980 18-2632006 45 E19688 1980 18-2222005 46 E19698 1980 18-2012005 47 E19718 1980 18-2692006 48 E19768 1980 18-2562006 49 E19798 1980 18-3372007 50 E19828 1980 18-2722006 51 E19838 1980 18-2962006 52 E19848 1980–8118-2262005 53 E19858 1980–8118-3122007 54 E19868 1980–8118-2152005 55 E19878 1980–8118-3242007 56 E19898 1981 18-3032006 57 E19908 1981 18-3102007 58 E19918 1981 18-2252005 59 E19928 1981 18-2782006 60 E19938 1981 18-3362007 61 E19948 1981 18-3052006 62 E19958 1981 18-2792006 63 E19968 1981 18-3152007 64 E19978 1981 18-1562004 65 E19988 1981 18-2372006 66 E19998 1981 18-0652002 67 E20008 1981 18-3092007 68 E20039 1981–8218-2852006 69 E20059 1981–8218-3082007 70 E20069 1981–8218-3252007 71 E20079 1981–8218-2362005 72 E20089 1981–8218-2752006 73 E20119 1981–8218-2552006 74 E20129 1981–8218-2732006 75 E20159 1981–8218-2612006 76 E20169 1981–8218-2322005 77 E20179 1981–8218-2992006 78 E20189 1981–8218-2492006 79 E20199 1981–8218-2522006 80 E20209 1981–8218-1942005 81 E20229 1981–8218-2112005 82 E20239 1981–8218-2672006 83 E20249 1981–8218-2592006 84 E20259 1981–8218-1932005 85 E20269 1981–8218-1962005 86 E20279 1981–8218-3192007 87 E20289 1981–8218-2102005 88 E20299 1981–8218-3272007 89 E20309 1981–8218-2232005 90 E20319 1981–8218-3042006 91 E20329 1981–8218-3012006 92 E20339 1981–8218-2462006 93 E20349 1981–8218-2542006 94 E20369 1981–8218-2472006 95 E20379 1981–8218-0372002 96 E20389 1981–8218-0742003 97 E20399 1981–8218-2302005 98 E20409 1981–8218-2412006 99 E20419 1981–8218-2762006 100 E20429 1981–8218-2272005 101 E20439 1981–8218-2342005 102 E20449 1982 18-2192005 103 E20459 1982 18-2382005 104 E20469 1982 18-2712006 105 E20479 1982 18-2682006 106 E20489 1982 18-2582006 107 E20509 1982 18-2392006 108 E20519 1982 18-2292005 109 E20529 1982 18-2182005 110 E20539 1982 18-0932003 111 E20549 1982 18-2572006 112 E20559 1982 18-0282002 113 E20569 1982 18-0792003 114 E20579 1982 18-2402005 115 E20589 1982 18-2532006 116 E20599 1982 18-3212007 117 E20609 1982 18-2502006 118 E20629 1982 18-2822006 119 E20639 1982 18-2422006 120 E20649 1982 18-2812006 121 E20659 1982 18-1922005 122 E20669 1982 18-2122005 123 E20679 1982 18-2452006 124 E20689 1982 18-3022006 125 E20699 1982 18-2912006 126 E20709 1982 18-2242005 127 E20719 1982 18-3282007 128 E20739 1982 18-2432006 129 E20759 1982 18-0732003 130 E20769 1982 18-2282005 131 E20779 1982 18-2442006 132 E20799 1982 18-1272004 133 E20819 1982 18-2512006 134 E20829 1982 18-2352005 135 E20849 1982 18-2172005 136 E20859 1982 18-2142005
Illustration The main picture shows Class 17E no. E1826, ex Class 6E1, Series 7, at Capital Park in Pretoria on 28 September 2006. The "17E" markings below the locomotive numbers on this and the following picture were the only means to visually distinguish Class 17E locomotives from unmodified Class 6E1 locomotives.
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