In the fifties, the New South Wales Government electrified the first 150 km of the Main Western Line to the north west of Sydney. The new locomotives of class 46 were built by Metropolitan-Vickers and Beyer, Peacock & Co. in England. Since the Australians also used 1,500 V DC, experience from the British classes 76 and 77 were incorporated into the class 46.
After more lines were electrified, some of the 40 locomotives were also used on the Main Northern Line and the Main South Line. They also hauled the Indian Pacific on a small portion. Until 1990, only two had been retired. It took until 1996 for all others to be retired and replaced by diesels, with five being preserved. 