MAIN AND ADVANCED SIGNALS

This page is updated at 22/03/2008.

INTRODUCTION

A) Main signals (1st and 2nd category) and advanced signals.

Main (Segnali di 1ª categoria) and advanced [or "warning"] (segnali di avviso) signals are of colour light or mechanical type. Usually light signals are used.

2nd category signals are used only in some old line and they are only mechanical.

In colour light signals, lights are fixed in a black panel (or signal screen) with a white border. In tunnel there are no panels.

Signals are usually put on a mast. The masts of advanced signals are coloured with black-white-black lines. In main light signals, the lower side of mast is black, the upper is grey.

Signals are usually on the left-hand side of the track. In this situation the signal screen is circular.

In stations, in single-track lines and on "either-direction working" lines, signals may be put on right-hand side of the track and they have a square panel with a square white border.
Signals put on right-hand side may be added with a white arrow in a black panel. The arrow is normally off. It turns on when signal shows any "clear" aspect.

Advanced (warning) signals (segnale di avviso) never show a red light.

If a signal is off (due to a light failure) or if it shows an unexpected aspect, it must be considered at stop position. If this signal is an advanced signal, driver, after stopping, can proceed but he must consider next main signal as showing "danger" position.

Advanced signals are put 800, 1000 or 1200 meters before the main signals according to the maximum speed of line.

When the distance between a main signal and the next advanced signal is less than 1,500 meters, the advanced signal is joined with the main signal in one "main-advanced" or "combined" signal (segnale di 1a categoria con avviso accoppiato).

Mechanical signals are made by a mast and an arm on left-hand side. Main signal arm is red, advanced signal arm is yellow.
The arm can assume two positions:

• horizontal: stop or main signal shows "warning";
• inclined in lower position (about 45 degrees): clear or main signal shows "clear".

When a mechanical advanced signal is found in "warning" position and main signal in "clear" position , main signal must be overtaken with speed reduction to 30 km/h.

Home and departure main signals, in junctions, may be multiple (candelabra signals). They are made by two or three simplex main signals put on the same mast (segnali multipli o a candeliere).

Upper arm signal is for trains addressed to the main track or to line without speed reduction, lower signals are for trains addressed to a diverging route with speed reduction (usually 30 km/h on switches).

If both signals are on lower arms, every track or line is diverging and has a speed reduction. Each signal is referred to a direction from left to right in the same order.

Some signals may have a black table with a white "P", "D" or "A" upper-case letter. These letters may be anyway "on" (bright) whether signal shows stop or shows a clear aspect. When signal shows stop, the letter may also flash (see "Signal Aspects").

Remember that in Italian double-track lines, trains usually travel on left-hand track.

B) Home signals

Home signal protects a station, a junction, and so on (any place that has switch points, level crossings, etc.) from trains coming from line.

Any station has al least one home signal. Some station may have more than one home signal from the same direction. In this case the first home signal met by the train is called "outer" home signal and has a yellow squared board with "EST." black letters. Following home signals are called "inner" and, if more than one, are numbered in descending order (INT., or ...,INT N°2, INT N° 1). At the end of entry route, the train reaches the station tracks.

All home signals may be subsidized by subsidiary signals (two flashing or steady horizontal white lights) used in case of main signal failure.

C) Exit signals

Exit signals are main signals. Usually they are block main signals too, or rather, they also protect the first block section after the station. They are usually put at the end of station tracks and allow trains to leave the station.

They are usually "distinct" that is any track has its exit signal. Sometimes they may be "group signal" that is a group of tracks have a unique exit signal.

In case of group signal, departure from station must be ordered by movement inspector, even if signal shows a clear aspect, except if track has its own "subsidiary exit signal": two vertical lights, usually off, that flash with white colour if exit signal is clear from this track. Subsidiary exit signal may be integrated in dwarf signal.

When an exit signal is put at the end of a loop (not running track), it may have on its mast a white triangular board with black borders.

This board orders a reduced speed of 30 km/h on exit route, except if it have "60" black ciphers. In this case it orders a reduced speed of 60 km/h.

Some station may have more than one exit signals. In this case, the last exit signal is called "outer" (ESTERNO) exit signal and has on its mast a white squared board with "EST." black letters. The exit signals before the last, are called, "inner" (INTERNO) exit signal. They may be one or more. If it is only one, it is simply called "inner" and has on its mast ad "INT." white board. If they are more than one, the are numbered in descending order: "INT. N° 2", "INT. N° 1" that is "..., inner #2, inner #1).

All home signals may be subsidized by subsidiary signals (two flashing or steady horizontal white lights) used in case of main signal failure. The outer exit signal is subsidized by an exit subsidiary signal (two flashing or steady horizontal blue lights).

B) Route speed to be respected in a service place

RFI (italian) train signals shows if line is clear on not and, also, the maximum speed to observe running through a station route. Signal shows a speed reduction, due to diverging route (or other reasons), only if it is less then maximum line speed, if not signal shows a clear "clear" for maximum line speed.

C) Aspects shown one a train has to stop in a station

When a train has to stop in a station and the stop is indicated in the timetable or was order to the train by special "prescription form", signals usually show a clear aspect in exit signal too. Anyway there are some situation where exit signal is to be kept in "danger" position until the train has stopped.

D) Speed confirmation table (Rappel).

A main signal may be subsidized by a "speed confirmation" table. This black table is normally "off" and may show one or two steady white stripes:

• no stripes (all off): maximum speed 30 km/h (or respect the speed given from advanced signal);
• one bright white stripe: maximum speed 60 km/h;
• two bright white stripes: maximum speed 100 km/h.

Clear with speed reduction of 60 km/h

Clear with speed reduction of 100 km/h (expect clear at 100 km/h)

SIGNAL ASPECTS

1A) Stop (danger).

1B) Permissive stop (automatic block lines).

Driver must stop and wait for 3 minute. If signal remains at stop position, driver may contact the dispatcher (DCO) or movement inspector (DM) to ask for news about the line ahead. If DCO/DM says that line is clear or in case of phone failure, driver may overpass the signal at maximum speed of 30 km/h and travelling on sight until next main signal. Speed reduction of 30 km/h must be kept until driver finds a signal that doesn't show "danger" or "clear, expect stop". For station signals (home and exit) if the letter "P" is on, it means that the station is unmanned.

One red light. Under the light there is a black table with a bright white steady upper-case "P" letter. (table can be white with a painting black upper-case "P" letter)

If such signals protect one or more level crossings (passaggi a livello), another table with "PL" letters has put on the mast. In this situation, if driver overpass the signal at "permissive stop" position, he has to respect special cares when pass through the LC.

1C) Permissive stop (axle-counter or manual block lines).

Driver must stop anyway. Then, he may overpass the signal at maximum speed of 30 km/h (if he is going to entry in/exit from a station). When he reached the line, he may proceed at maximum line speed Speed reduction of 30 km/h must be kept until driver finds a signal that doesn't show "danger" or "clear, expect stop". The "A" letter ensures that line is clear and block system is rightly working. "A" letter is used in exit signals or block signals, "D" letter in home signals. For station signals (home and exit) if the letter "A" or "D" is on, it means that the station is unmanned. If such signals protect one or more level crossings (passaggi a livello), another table with "PL" letters has put on the mast. In this situation, if driver overpass the signal at "permissive stop" position, he has to respect special cares when pass through the LC.

One red light. Under the light there is a black table with a bright white steady upper-case "A" or "D" letter.

1D) Permissive stop (automatic block lines). Switch failure.

Driver must stop and wait for 3 minute. If signal remains at stop position, driver may contact the dispatcher (DCO) or movement inspector (DM) to ask for news about the line ahead. If DCO/DM says that line is clear or in case of phone failure, driver may overpass the signal at maximum speed of 30 km/h and travelling on sight until next main signal. Speed reduction of 30 km/h must be kept until driver finds a signal that doesn't show "danger" or "clear, expect stop". In addition of cautions before, driver must stop before any switch point or group of switch point, verify that they are intact and set for main route and then go on with care. You can find these kind of signal in "automatic block" lines. For station signals (home and exit) if the letter "P" is on, it means that the station is unmanned.

One red light. Under the light there is a black table with a bright white flashing upper-case "P" letter.

1E) Permissive stop (axle-counter or manual block lines). Switch failure.

Driver must stop anyway. Then, he may overpass the signal at maximum speed of 30 km/h (if he is going to entry in/exit from a station). When he reached the line, he may proceed at maximum line speed Speed reduction of 30 km/h must be kept until driver finds a signal that doesn't show "danger" or "clear, expect stop". In addition of cautions before, driver must stop before any switch point or group of switch point, verify that they are intact and set for main route and then go on with care. The "A" letter ensures that line is clear and block system is rightly working. "A" letter is used in exit signals or block signals, "D" letter in home signals. For station signals (home and exit) if the letter "A" or "D" is on, it means that the station is unmanned. If such signals protect one or more level crossings (passaggi a livello), another table with "PL" letters has put on the mast. In this situation, if driver overpass the signal at "permissive stop" position, he has to respect special cares when pass through the LC.

One red light. Under the light there is a black table with a bright white flashing upper-case "A" or "D" letter.

1F) Stop, proceed then stop again.

	Driver has to stop, if possible, before the signal. After stopping, if the line ahead is clear, driver may go on with care until the train is all after the signal, then he must stop and wait until signal will show "clear" position or until he receive special order to enter in the station.
Only in mechanical signalling system. A red arm with a black painted "2" in horizontal position. One red light (during the night)

2) Stop. Driver may overpass the signal with care (Subsidiary signal).

	In case of signal failure driver, after stopping, may overpass the signal if subsidiary signal is on. if subsidiary signal shows two white steady light, driver may overpass the signal at maximum speed of 30 km/h and travelling on sight until next main signal. Subsidiary signal with white lights is put on mast of home signals and of "inner" exit signal.
One red light. Two horizontal steady white lights.

 

2bis) Stop. Switch failure. Driver may overpass the signal with care (Subsidiary signal).

In case of signal failure driver, after stopping, may overpass the signal if subsidiary signal is on. if subsidiary signal shows two white flashing light, driver, must to take orders verbally by the dispatcher (DCO) and then he may overpass the signal at maximum speed of 30 km/h and travelling on sight until next main signal. In addition of cautions before, driver must stop before any switch point or group of switch point, verify that they are intact and set for main route and then go on with care. Subsidiary signal with white lights is put on mast of home signals and of "inner" exit signal.

One red light. Two horizontal flashing white lights.

3) Stop. Driver may overpass the signal with care (Subsidiary signal for exit signal).

In case of signal failure driver, after stopping, may overpass the signal if subsidiary signal is on. if subsidiary signal shows two blue steady light, driver may overpass the signal at maximum speed of 30 km/h and travelling on sight until next main signal. Line is clear. Block system and LC work properly. This kind of subsidiary signal blue white lights is put on mast of exit signals (simple) and of "outter" exit signal.

One red light. Two horizontal steady blue lights.

3bis) Stop. Switch failure. Driver may overpass the signal with care (Subsidiary signal for exit signal).

In case of signal failure driver, after stopping, may overpass the signal if subsidiary signal is on. if subsidiary signal shows two blue flashing light, driver, must to take orders verbally by the dispatcher (DCO) and then he may overpass the signal at maximum speed of 30 km/h and travelling on sight until next main signal. In addition of cautions before, driver must stop before any switch point or group of switch point, verify that they are intact and set for main route and then go on with care. Line is clear. Block system and LC work properly. This kind of subsidiary signal blue white lights is put on mast of exit signals (simple) and of "outter" exit signal.

One red light. Two horizontal flashing blue lights.

4) Clear at 30 km/h. "Next main signal shows stop but it is at very short distance" or "enter a short track" or "enter a partially occupied track".

	Line clear. Maximum speed 30 km/h Train goes toward a main route (not diverging). Driver may: expect stop at very stop distance (between 350 and 600 meters); enter a short track; enter a partially occupied track. The advanced signal always shows one yellow light (expect stop).
Two yellow lights.

5) Clear for a diverging route at 30 km/h. "Next main signal shows stop but it is at very short distance" or "enter a short track" or "enter a partially occupied track".

	Line clear. Maximum speed 30 km/h Train goes toward a diverging route. Driver may: expect stop at very stop distance (between 350 and 600 meters); enter a short track; enter a partially occupied track. The advanced signal always shows one yellow light (expect stop).
One red light and two yellow lights.

6) Expect stop. Clear, expect stop.

	Table #1 is put before of a 2nd category signal at brake distance. Driver must always expect that next 2nd category signal shows stop. Tabel #2 is put before a 1st category home signal that protects an unmanned station in simplified CTC single-track lines (in these stations trains always force the exit point).
1) A rhomboid yellow table with a yellow light. 2) A square yellow table with a yellow light

7A) "Expect clear at maximum line speed" or "Clear" or "clear at maximum line speed, expect clear at maximum line speed".

7B) Direction table.

DIRECTION TABLE WITH A BRIGHT WHITE NUMBER

The number is on only when main signal shows a clear aspect. The number indicates train direction in a junction. Lines are numbered from left to right. Driver find "his" number in timetable of in "Line Booklet".

8) Clear. Early advice of stop or of clear with speed reduction.

Clear at maximum line speed, expect a first "combined" signal that shows "clear at maximum line speed" followed by a second signal showing "stop" or "clear with speed reduction". Distance between first "combined" signal and second signal is less than normal brake distance. In line without RSC system (on-board aspect signal transmission) this aspect is use even if distance between last two signals is normal.

One flashing yellow light.

9) Clear at reduced speed. Early advice of stop or of clear at speed reduction.

A red light and a yellow flashing light.

Clear at reduced speed (30, 60 or 100 km/h as shows in advanced signal), expect a first "combined" signal that shows "clear at maximum line speed" followed by a second signal showing "stop" or "clear with speed reduction". Distance between first "combined" signal and second signal is less than normal brake distance.
In line without RSC system (on-board aspect signal transmission) this aspect is use even if distance between last two signals is normal.

10) Clear at reduced speed. Expect clear at maximum line speed.

 

One red light and one green light.

Clear at reduced speed (30, 60 or 100 km/h as shows in advanced signal). Next signal shows "clear at maximum line speed".

Signal may be subsidized by a "speed confirmation table".

10bis) Clear at reduced speed at 60 km/h. Expect clear at maximum line speed.

One red light and one green light.
Signal is subsidized with "speed confirmation table" that shows one white horizontal stripe.

Clear at reduced speed of 60 km/h. Next signal shows "clear at maximum line speed".

Signal may be subsidized by a "speed confirmation table".

10ter) Clear at reduced speed at 100 km/h. Expect clear at maximum line speed.

One red light and one green light.
Signal is subsidized with "speed confirmation table" that shows two white horizontal stripes.

Clear at reduced speed of 100 km/h. Next signal shows "clear at maximum line speed".

Signal may be subsidized by a "speed confirmation table".

11)  Clear at reduced speed. Expect stop.

One red light and one yellow steady light.

Clear at reduced speed (30 or 60 km/h as shows in advanced signal). Next signal shows "clear at maximum line speed".

Signal may be subsidized by a "speed confirmation table".

12) Expect clear at 30 km/h. Clear at maximum line speed, expect clear at 30 km/h.

  

One group of "yellow and green" steady lights.

Clear at maximum line speed. Next signal shows clear at 30 km/h.

13) Expect clear at 60 km/h. Clear at maximum line speed, expect clear at 60 km/h.

 

One group of "yellow and green" flashing simultaneously lights.

Clear at maximum line speed. Next signal shows clear at 60 km/h.

14) Expect clear at 100 km/h. Clear at maximum line speed, expect clear at 100 km/h.

One group of "yellow and green" flashing alternately lights.

Clear at maximum line speed. Next signal shows clear at 100 km/h.

15) Clear at reduced speed, expect clear at 30 km/h.

One red light, below, one group of "yellow and green" steady lights.

Clear at reduced speed (30, 60 or 100 km/h as shows in advanced signal). Next signal shows "clear at 30 km/h".

Signal may be subsidized by a "speed confirmation table".

16) Clear at reduced speed, expect clear at 60 km/h.

One red light, below, one group of "yellow and green" flashing continously lights.

Clear at reduced speed (30, 60 or 100 km/h as shows in advanced signal). Next signal shows "clear at 60 km/h".

Signal may be subsidized by a "speed confirmation table".

17) Clear at reduced speed, expect clear at 100 km/h.

One red light, below, one group of "yellow and green" flashing alternately lights.

Clear at reduced speed (30, 60 or 100 km/h as shows in advanced signal). Next signal shows "clear at 100 km/h".

Signal may be subsidized by a "speed confirmation table".