This photo at Kensington was almost certainly taken to show the just installed 3 position signals which were put into service on April 1 1924. The interlocked gates were replaced by boom barriers on Feb 25 1965 but the signalbox is still very much in use as is the grain handling facility seen in the distance.
The wagon seen pushed up against the buffers was a WW (1, 2 or 3) that was formerly a joint stock baggage car in Melbourne - Adelaide service. It was removed from this service in about 1907 as the E cars were built.