Legal aspects
Signalling is governed by strict rules, released by the Federal Office of Transport. The rules for railway operation are laid out in the Swiss Rail Service Regulations (''Fahrdienstvorschriften'' (in German), ''Prescriptions de circulation des trains (PCT)'' (in French), ''Prescrizioni sulla circolazione dei treni (PCT)'' (in Italian)), of which the latest version was issued in 2012, valid since 1 July 2012 and are based on article 11a of the Ordinance of 23 November 1983 on the Construction and Operation of the Railways (Railways Ordinance, RailO).Light signals
Swiss light signals are divided into two classes, recognizable by the difference in shape of the signal: type L (for Light) and type N (for ''numérique'' (digital)). Type L was developed many years ago. The N system was developed for theL type
L type signals remain the most widespread in the country. It authorizes trains to proceed at their normal speed, to slow them down or to stop them. The speed reductions imposed by type L signals, when they are protecting a station or a crossover, only apply to the points zone protected by the signal and not normally to the stretch of track beyond the points. Thus if a signal presents the aspect 2 (maximum speed 40 km/h at the signal), the 40 km/h limit applies from the signal and over the points concerned. ; as soon as the train has passed the last points in deviated position it can accelerate to the operating speed. This way of operating requires that the drivers understand for any signal which points are concerned. A signal presenting the 'stop' aspect cannot be passed under any circumstances without a formal order from the train controller. This order can be transmitted in writing or by radio. In the latter case the driver must repeat the order word for word. Once this order has been received, the driver can proceed at a speed slow enough that they may stop short of any obstruction de 40 km/h. This restrictive procedure requires very slow operation. There is a complementary signal, shown below, which gives the order 'Proceed on sight' without needing a written order, so as to avoid huge delays in case a signal breaks down. In some cases, mostly entering stations, home signals and distant signals can be found on the same mast; in this case the distant signal is linked to the next home signal. On lines where the blocks are relatively close a system called ''combined'' has been developed. The signal can then be presented on the same plate is a distant signal (warning or announcement of speed), an image of the home signal (track clear, stop or speed limit). To be recognized as a home signal, where the alignment of the lamps would not allow, the combined signal has a distinctive supplementary plate. In combined L-type signals the distant signal ‘track clear’ is not shown but implied by the ‘proceed’ aspect. If two successive signals show speed limits, the first speed limit shown must be applied from the second signal, even if not shown explicitly.N Type
N type signals are progressively replacing L type signals on the CFF/SBB network and are starting to be used by other companies, mostly the BLS. In contrast to L type signals, not all N type home signals are preceded by a distant signal, as all N signals are capable of speed signalling and thus play the role of a distant signal. Thus, if a driver passes an N type signal showing a speed aspect, he must maintain this speed until he has recognized the aspect of the next signal, which may continue to impose a speed restriction. Speed signalling is no longer based on combinations of green and yellow, but on one colour accompanied by a single digit display indicating the speed. Thus the green aspect means 'track clear' and if a digit is displayed, with a speed restriction. The yellow aspect still means a warning or a speed restriction if a digit is displayed and a red aspect remains an absolute stop signal, only to be passed with a formal order or with safety equipment deployed. In order to distinguish clearly between the two, distant signals use square plates while home signals use circular plates.Shunting signals
In Switzerland, shunting manoeuvres can be controlled either by shunting signals or dwarf signals. The maximum speed allowed for shunting is 30 km/h. This can be increased in special cases to 40 km/h. In any case speed must be compatible with visibility, local conditions and braking power. Shunting signals are not integrated with automatic train protection systems such asDwarf signals
In contrast to shunting signals, dwarf signals protect paths and are interlocked. Points in zones equipped with dwarf signals do not have points indicators. Dwarf signals have three aspects: Dwarf signals are usually positioned on the left of the tracks and only apply to that track. In case it is positioned on the right hand side of the track it has an illuminated indicator (arrow) to make clear for which track it is valid. They are set to allow the passage of trains as well as the standard light signals for mainline movements. The last dwarf signal before entering the main line will show a Proceed aspect for a train or a Proceed with caution aspect for a shunting movement. Whatever kind of signal is used, the permission to move is given to the guard in charge who will then himself authorize the movement to start. This is to avoid accidents to the team who may be working on a vehicle. Remaining sections still need to be translated. French source text in talk sectionComplementary light signals
There are many types of complementary light signals to be found on the Swiss Federal Railways network. Only the most common ones will be shown here. Complementary signals are mostly used with type L signals, but some are used with type N. They can also be independent of either type. Mostly they are used * to solve problems posed by grouped L signals * to mitigate difficulties caused by the use of replacement equipment * to communicate orders and information which cannot be communicated with standard signalsComplementary signals for grouped L type signals
A grouped signal is an L type signal which applies to several tracks, usually in stations. The rules covering the presence of several trains waiting at a grouped signal dictate that the traffic controller must indicate to all trains that the signal will pass to 'go' and that they must not start. The train which has not received this order is free to depart. This system is rather slow, so complementary signals are used. An illuminated numeric display is used to indicate which track is concerned by the signal, track 1 always being the one closest to the station building. Trains standing on other tracks know that this signal implies the 'halt' aspect for their tracks. 'Track free' indicators are also used which indicate which aspect applies to track where the indicator is installed. In this example, the driver knows that the signal with aspect 2 permits him to start.Auxiliary signals
Auxiliary signals are used to send permission to pass a signal which has failed or is showing the 'stop' aspect. This avoids the use of formal orders which would delay trains too much. An auxiliary signal allows the driver to proceed at sight without needing communication between the driver and the traffic controller. The auxiliary signal for N type signals is flashing red.Other complementary signals
In some stations, signals are needed to communicate the ''right away'' to the driver. He will then know that boarding is complete, the doors are closed and that he may depart. This signal is actuated by the guard just before boarding himself. These signals are to be found along the platform and sometimes at the departure signal. Other signals include, for example, an indication that a passenger has requested a stop at a request stop, the voltage in a variable voltage section or an order to test the brakes.Signs
Signs are used to protect or indicate a fixed feature such as a speed limit or a level crossing. There are a number of signs that are all designed to protect or to indicate a fixed feature such as a speed restriction or aReferences