SCT class

Downer EDI Rail GT46C-ACe

SCT Logistics SCT class locomotives at Laverton in March 2008

Type and origin Power type Diesel-electric Builder Diesel Locomotive Works, EDI Rail, Cardiff Model Electro-Motive Diesel GT46C-ACe Build date 2007-Present Total produced 79 & 6 (DLW)

Specifications Configuration: ​  • UIC Co-Co Gauge 1,435 mm (4 ft 8 1⁄2 in) Length 21.2 m (69 ft 7 in) Loco weight 134 t (132 long tons; 148 short tons) 139 t (137 long tons; 153 short tons) Fuel type Diesel Prime mover Electro-Motive Diesel 16-710 G3C-ES Alternator Electro-Motive Diesel TA17-CA9E Traction motors Siemens 1TB 2630

Performance figures Maximum speed 115 km/h (71 mph) Power output 3,350 kW (4,490 hp) Tractive effort 500 kN (110,000 lbf)

Career Operators Indian Railways Downer Rail Locomotive Demand Power Genesee & Wyoming Australia Pacific National SCT Logistics Whitehaven Coal Southern Shorthaul Railroad Number in class 79 First run 2007 Current owner Indian Railways Aurizon Downer Rail Locomotive Demand Power Genesee & Wyoming Australia Pacific National SCT Logistics Whitehaven Coal Southern Shorthaul Railroad Disposition 79 in service.

The GT46C ACe is a model of diesel electric locomotive designed and built by Downer Rail, Cardiff using Electro-Motive Diesel components between 2007 and 2013.

The first units were built as the SCT class for freight operator SCT Logistics from 2007 followed by the WDG class in India, TLD class for Downer Rail's Locomotive Demand Power division, the TT class for Pacific National, the GWA class for Genesee & Wyoming Australia, the WH class for Whitehaven Coal, and the SSR class for Southern Shorthaul Railroad.

The class was a new design for Australian conditions based on other locomotives produced by Downer EDI Rail, such as the narrow gauge GT42CU AC purchased by Queensland Rail and Pacific National and the GT46C purchased by Westrail, Freight Australia and FreightLink. The GT42CU AC used a 12-cylinder EMD 710 engine, based on the USA built SD70MAC with scaled down traction motors, while the GT46C used a 16-cylinder EMD 710 engine with DC traction systems. The American SD70ACe was EMD's 2nd generation AC loco with IGBT inverters, but was too large and heavy for the Australian interstate standard gauge network, weighing in at 188 tonnes when the limit was 134 tonnes. In addition, the GT46C design was already at the 134 tonne limit, even before adding inverters, heavier traction motors and more cooling capacity for higher power engine, and there was a requirement that fuel capacity could not be sacrificed.

The locomotive has AC traction equipment, with a Mitsubishi Electric package also used on the SD70ACe, including a TA17 traction alternator, CA9E companion alternator and six ITB 2630 traction motors, along with solid state IGBT inverters. The prime mover is a turbocharged 16-cylinder EMD 710. New technology used included passive steer bogies, to reduce flange wear on corners. The class were built at Cardiff, with the frames constructed at Port Augusta, and the bogie frames at Kelso, reliability was instilled in this class through the tireless efforts of Darrell Sherry, and the tight document control of Rob McNulty. The Downer Rail GT46C ACe and the PL class are the only locomotives to bear Rob's personal stamp of approval.