Of Interlockings And Other Machines ...: Switzerland 1988: "Diamond crossing" at Kerzers

Deutsche Version dieses Postings

The signal box at Kerzers is preserved as a museum, thus one still can visit the interlocking apparatus shown here. My photos, however, were made when the interlocking was still controlling the points and signals of Kerzers station, where the lines of BLS and SBB cross each other.

The four lines emanating from Kerzers are

the SBB line towards Lyss via Fräschels,
the BLS line towards Neuchâtel via Müntschemier,
the BLS line in the opposing direction to Bern via Ferenbalm and Gummenen
and the SBB line towards Murten and Payerne via Galmiz.

Here is a track plan of Kerzers, showing the main tracks and the stop signals (click opens a readable PDF file):

In addition to the typical routes entering and leaving the station, Kerzers also allowed a train to leave the goods track 14. Moreover, it was possible to leave and enter the SBB track towards and from the BLS line to Ferenbalm, presumably so that goods trains could reach the part of the station with the goods shed without too much zig-zagging:

From Müntschemier into 6,5,4
To Müntschemier from 6,5,4
From Fraeschels into 3,2,1
To Fraeschels from 3,2,1
To Fraeschels from 14
To Galmiz from 3,2,1
To Galmiz from 3,2,1
To Ferenbalm from 1
To Ferenbalm from 6,5,4
From Ferenbalm into 1
From Ferenbalm into 6,5,4

The signal box contained, to the best of my knowledge, the last interlocking frame that was mechanically connected to the corresponding command frame in the traffic bureau. The following pictures show that command frame, which used large cranks for transmitting the respective route commands to the signal box. One can see the inclined arrow that indicates that a route is set from track 3 towards Galmiz. The rectangular mechanical track occupation indicator for track 3 ("Gleis III") is showing red because of that line:

Command frame, traffic bureau, Kerzers, 18.8.1988

The following pictures show the command frame with the route set from track 3 towards Galmiz:

Command frame, traffic bureau, Kerzers, 18.8.1988

A somewhat "artistic" picture of all the route cranks:

Command frame, traffic bureau, Kerzers, 18.8.1988

The track panel, which contains the signal indicators, is a later addition to this original Schnabel&Henning frame:

Track panel with signal indicators, traffic bureau, Kerzers, 18.8.1988

Detail of track panel, Kerzers, 18.8.1988

Something was improved on the outside of the signal box—new lamps, new paint, new something else?

Signal box, Kerzers, 18.8.1988

Here is a picture of the complete interlocking frame inside the signal box. On the left and the right are the route releases (which are moved via the cranks in the traffic bureau), in between are the points and signal levers. On the very left and right, line block operation panels had been added later:

Lever frame, Kerzers, 18.8.1988

The original builder's plate from Bruchsal does not show a year—according to the website of the preservation group, the frame was built in 1896:

Builder's plate, Kerzers, 18.8.1988

The signal levers are still in place, however, because the station had been resignalled with light signals, their wheels are wound by brake bands, and the signals change their positions via electrical contacts:

Lever frame, Kerzers, 18.8.1988

On the right route release, one can see the turned route wheel for an outgoing route from track 1 towards Fräschels:

Route levers, Kerzers, 18.8.1988

Some points had been converted to electrical points machines—this can be inferred from the brake bands around some points levers. The leftmost, blue lever moves the shunting signal R, which guards the intersection of the two lines: