Electro-mechanical interlocking at Ciampino, 1990

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This is one of the merriest photos around signalling equipment that I have ever taken:

Interlocking and traffic director, Ciampino, May 1990

The frame is an electro-mechanical interlocking or, in Italian parlance, an "apparato centrale elettrico" (A.C.E.). More precisely it is called "apparato centrale elettrico a leve individuali", i.e., "interlocking frame with individual levers"; with the longer abbreviation A.C.E.L.M., meaning "apparato centrale elettrico a leve manuali", because A.C.E.L.I. is taken by interlocking frames with buttons. Term like "central apparatus" have been used in many languages to designate interlocking frames, among them in German, Swedish and, here, Italian.

The colours used on this lever frame ("banco di manovra") are, according to this Italian webpage:

• black for points levers and points locks levers;
• blue for route levers;
• red for stop signals;
• yellow (or actually orange) for distant signals.

On this picture, a route from Velletri into track I has been set up—on the far right, one can see the pulled levers of the home and distant signals:

Interlocking frame, Ciampino, May 1990

This picture shows the track and signal panel. Occupied tracks were indicated by a dark light strip (in contrast to modern electrical frames in most countries, were—typically red—lights represent occupied tracks). The advantage of this old technology was, of course, that burnt??? lamps would not compromise the safety of the system (more modern frames use multiple lamps, where the probability that all of them fail is negligible).

It is interesting that this panel is, as of today, still shown in the official training documents for these frames provided by RFI (Rete Ferroviaria Italiana, i.e., the Italian railway infrastructure provider) on page 36:

Track and signal panel, Ciampino, May 1990

Unfortunately, I took only these few photos at Ciampino (and I wonder how I got the permission to take the photos at all; some waving of hands and much smiling must have been part of the exercise). A final picture shows starting signal DN at track I, where we left Ciampino:

Starting signal DN, Ciampino, May 1990