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Marshalling yard signaling

The freight yard of "Marşandiz", just outside Ankara and near Behiçbey, is not under CTC  but locally controlled by a specific relay interlocking system. The yards of Haydarpasa and Halkalı were equipped with an identical system. This system for both three yards was delivered in the early 1990's by Nippon Signal.

The yard is fully under control of one local signal room. The operator presses a pushbutton at the entrance and the exit of the route that he wants to set, and all switch operations and signal clearing is done automatically. All points are electrically operated and electrically interlocked. Track circuits prevent the change of a point if a train is present.

This local control room oversees also the access to locally connected installation. At Marşandiz, access to the locomotive depot and to the railway factory in under local control.  

In addition, a two aspects (red / green) signaling control the movements of the trains. All signals are ground type (see picture). I assume the green means something like "proceed with reduce speed" as no indication is given regarding the aspect of the next signal.

The operator has both a traditional telephone and a radio. All conversation are dutifully recorded. The operator keeps also a log book in which train movements are recorded.

Marsandiz control room

Marsandiz control room. In the foreground, the push button panel. In the background, the mimic display panel. November 2003. Photo JP Charrey

A two aspects signal at Marsandiz

A two aspects signal at Marsandiz. November 2003. Photo JP Charrey