Swedish railway signalling

__NOTOC__The signalling system used on standard gauge railway network in Sweden is based on the traditional mechanical semaphore signals. Currently only the color-light signals are used, together with the Automatic Train Control system.

Aspects – Home signals

Aspects may seem a little inverted, since a single green light means "clear", two green lights "Clear 40" and three green lights stands for "Clear 40 short path". In other words: "more green means more cautiously".

Stop (Stopp)

Stop aspect ("Stopp" in Swedish) means that the signal must not be passed without permission from the traffic control. During shunting operations permission to pass a home signal displaying "stop" may be given with a radio or with a dwarf signal.

Clear 40 short path (Kör 40 kort väg)

Clear 40 short path aspect ("Kör 40 kort väg" in Swedish) authorises the driver to pass the signal at a maximum speed of 40 km/h (25 mph). There may be another train as close as 250 meters (820 feet) beyond the signal.

Clear 40 (Kör 40)

Clear 40 aspect ("Kör 40" in Swedish) authorises the driver to pass the signal at a maximum speed of 40 km/h (25 mph): a more favourable speed can be shown through ATC driver display. The train will enter on a diverging path through a railway turnout located beyond the signal.

The next signal might be displaying stop, so the driver must approach next signal cautiously and be prepared to stop short of next signal.

Clear expect stop (Kör vänta stopp)

Clear expect stop aspect ("Kör vänta stopp" in Swedish) authorises the driver to pass the signal at a maximum allowed speed. There are no turnouts set against the train. The next signal is displaying "stop", so the driver must decrease speed and approach the next signal prepared to stop short of it.

The next signal can be as close as close as 800 meters (2,625 feet) or as far away as 3,000 meters (9,840 feet). If the distance to next signal is more than 3,000 meters, a separate free-standing distant signal is used to govern the approach to that signal.

Clear expect 40 (Kör vänta 40)

Clear expect 40 aspect ("Kör vänta 40" in Swedish) authorises the driver to pass the signal at a maximum allowed speed. There are no turnouts set against the train. The next signal is displaying "Clear 40 short path" or "Clear 40", so the driver must decrease speed and approach the next signal prepared to pass it at a speed not exceeding 40 km/h (25 mph) or the speed shown on the ATC driver's display.

The next signal can be as close as close as 800 meters (2,625 feet) or as far away as 3,000 meters (9,840 feet). If the distance to next signal is more than 3,000 meters, a separate free-standing distant signal is used to govern the approach to that signal.

Clear expect clear (Kör vänta kör)

Clear expect clear aspect ("Kör vänta kör" in Swedish) authorises the driver to pass the signal at a maximum allowed speed. There are no turnouts set against the train. The next signal is displaying a "clear" aspect.

The next signal can be as close as close as 800 meters (2,625 feet) or as far away as 3,000 meters (9,840 feet). If the distance to next signal is more than 3,000 meters, a separate free-standing distant signal is used to govern the approach to that signal.

Clear (Kör)

Clear aspect ("Kör" in Swedish) authorises the driver to pass the signal at a maximum allowed speed. There are no turnouts set against the train. The next signal will be a free-standing distant signal.

Aspects – Distant signals

Distant signals are informational signals used to give an advanced warning about the next home signal. Distant signal are typically located 1,000 to 1,200 meters (3,280 to 3,940 feet) in advance of the home signal in question.

Aspects – Dwarf signals

Dwarf signals are used as shunting signals. There are also types of dwarf signals used as stand-ins for home signals, where the available space does not permit installing a home signal.

Sources

* [http://www.thesignalpage.nl Swedish signalling section of The Signal Page (TSP)]
* [http://home.swipnet.se/~w-54462/signalfakta.htm Signalfakta by Per Forsström (in Swedish) ]

Fail Safe

Because the aspects are in reverse with more green lights meaning slower the aspects aren't Fail Safe, so lamp proving is needed to prevent lamp failure giving a faster aspect.

Single and Double Green signals work the other way with Norwegian railway signalling and it would be unsafe for drivers to cross the border, unless ATP were fitted.