Jump to content

Finnish railway signalling

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by 93.106.144.131 (talk) at 20:46, 1 December 2010 (Main signals: Added crude diagrams of the old system, still used in Helsinki area. Feel free to make better diagrams.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

A main and distant signal combined in a single post. The main signal (upper) is showing the Proceed 35 aspect and the distant signal shows the Expect 35 aspect.

The signalling system used on the railway network in Finland comprises color-light signals and fixed signs, used together with the Automatic Train Control system.

Main signals

The main signal can have any of the following aspects:

Aspect Meaning Old system (Helsinki area)
Stop The signal must not be passed.
Proceed The signal may be passed with the maximum allowed speed.
Proceed 35 The signal may be passed and the maximum speed of 35 km/h (22 mph) is in effect from the next switch, which may lead to the diverging route. An ATC cab display may authorize a higher speed, typically 80 km/h (50 mph). The speed is in effect until the next main signal or after leaving the station area. The route may also lead to an occupied track section, but only if the driver has received a preliminary announcement.

If a main signal doesn't protect any switches or the speed restriction on a diverging route is the same as straight route, the signal doesnt't need to show the Proceed 35 aspect and therefore the yellow bottom light may be absent. The two lamp version of the old system has the lights reversed, i.e. red at the top and green at the bottom.

Distant signals

The distant signal is located at least 1,200 metres (3,900 ft) before the main signal. It may also be located in the same post with a main signal, below it. In this combined arrangement, whenever the main signal shows a stop aspect, the distant signal doesn't show any aspect at all.

A distant signal can have any of the following aspects:

Aspect Meaning
Expect Stop The next signal shows the Stop aspect. The train route may also be set to a track section without further signals, e.g. toward unsignalled line or a buffer stop.
Expect 35 The next main signal shows the Proceed 35 aspect.
Expect Proceed The next signal shows the aspect Proceed.

Block signals

A block signal can show any of the following three aspects:

Aspect Meaning
Stop The signal must not be passed.
Proceed, expect stop The signal may be passed. The next main or block signal is showing a Stop aspect.
Proceed The next main or block signal is showing a permitting aspect. The following two blocks are not occupied.

Block signals are being replaced by combinations of main and distant signals, and no new block signals will be installed.

Dwarf signals

A dwarf signal showing the Stop aspect

A dwarf signal can have any of the following aspects:

Aspect Meaning
Stop The signal must not be passed.
Proceed with caution The signal may be passed, but the track may be occupied by cars or another train.
Signal cancelled The signal may only be passed by the unit that has a permission to do shunting or track work.

A dwarf signal may also be placed in conjunction with a main signal. If the main signal shows any other aspect than Stop, the dwarf signal shows the Proceed with caution aspect.

Bridge signals

A bridge signal showing the Proceed aspect

Bridge signals are small signals used to display the orientation of a moveable bridge. They can have either of the following aspects:

Aspect Meaning
Stop The bridge is open and the signal must not be passed.
Proceed The bridge is closed and the signal may be passed.

Repeaters

Repeaters are sometimes used to repeat the aspect of the main signal, in places where the main signal is not clearly visible.

Aspect Meaning
The main signal is showing the Stop aspect.
The main signal is showing some Proceed aspect.

Helsinki Metro

The Helsinki Metro signals differ from those used by the railways.

Main signals

Some aspects may be shown using a signal with only three lights, pictured on the right.

Aspect Meaning
Stop The signal must not be passed. Forced stopping magnet is active.
Proceed The signal may be passed with the maximum allowed speed.
Proceed 35 The signal may be passed. Speed limit after the signal is 35 km/h (22 mph). The train may enter a diverging track through a switch.
Coupling The signal may be passed, but the track may be reserved or is an ending track. Speed limit after the signal is 20 km/h (12 mph).
Exception Drive at driver's responsibility. Forced stopping magnet is active. Speed limit after the signal is 35 km/h (22 mph).

Distant signals

Aspect Meaning
Expect other than Proceed The next main signal is showing one of the aspects Stop, Proceed 35 or Coupling.
Expect Proceed The next main signal is showing the Proceed aspect.

Media related to Railway signals in Finland at Wikimedia Commons