Guide to Trainz…

SIGNALLING

INTRODUCTION

The Trainz signalling system has been expanded to include additional aspects for more prototypical operation. It is a first look at some of our plans for signalling in future Trainz modules, and while it isn’t intended to be a true reflection of real life at this stage, it offers some satisfying possibilities for signalling your tracks.

In order to make effective use of the system, it’s necessary to become familiar with it’s operation, and how it relates to prototype systems.

If you do not wish to explore the expanded signalling system, you can continue to use the original 3 aspect system, as it’s function is unchanged. The following signals are used in exactly the same way as their Trainz predecessors….

BR_04

BR_04RH

QR_04

QR_04RH

SAR_004

SAR2_004

SAR_G005

USA_04

USA2_04

USAG_005

sig3gant

sig3rolft

sig3rorgt

pkp lightpost 3

pkp lightpost 3 long

pkp lightpost 3 side

pkp lightpost 3 side long

The expanded system is capable of displaying the following indications during a Driver session….

0 STOP

1 STOP THEN PROCEED

2 CAUTION AND LEFT DIVERGE

3 CAUTION AND RIGHT DIVERGE

4 CAUTION

5 PROCEED AND LEFT DIVERGE

6 PROCEED AND RIGHT DIVERGE

7 ADVANCED CAUTION

8 PROCEED

AI trains respond only to the standard aspects 0, 4 & 8. If an AI train encounters a signal displaying aspect 5 (proceed and left diverge), it will operate according to the next signal it is programmed to recognise, which is 4 (caution). If an AI train encounters a permissive signal such as an automatic signal at stop (aspect 1), it will consider this to be an absolute signal at stop (aspect 0), and will not proceed into the block until it considers the signal to be at caution or clear.

BR & QR

There is essentially no difference between the BR & QR systems; the only notable difference for our purposes is that the QR position lights are reversed for right hand drive. These lights are never used during a Driver session, but may be activated during scenarios.

The position lights are used to call trains into occupied blocks for shunting etc.

The BR & QR systems are capable of 2-aspect signalling, simple 3-aspect route signalling, and 4-aspect signalling. There is no support for 4 aspect route indicators at this time.

	As depicted in Fig.0; the QR and BR systems include signals with lunar lights for depicting divergence to either left or right. For the purpose of Trainz, these are suitable for use on 3-way junctions only.
Fig.0

		For the purpose of signalling ordinary junctions, there are dedicated left and right indicators as shown in Fig.1. See further details about their use under SIGNAL PLACEMENT.
Fig.1

	Fig.2 depicts a distant signal; it will not protect the rear of your train after it has been passed, as it is not capable of displaying red. The distant or approach signal is placed in rear of a home signal, and is used to give the driver an early indication of the state of the home signal ahead. If the home signal is at CLEAR the distant signal will display clear. If the home signal is at STOP, the distant signal displays caution. Never use distant signals to protect junctions or other crossings, as they are incapable of stopping AI controlled Trains. The signal in Fig.3 above is another 2-aspect signal, this one is capable of displaying STOP and CLEAR only. Under the 2-aspect system, the driver has no warning of the state of the next signal other than on sighting in the visible distance ahead. These signals should be used in low speed areas; or interleaved by distant signals in normal speed areas.
Fig.2		Fig.3

USA

The USA signalling system in Trainz is based on the NORAC rules. The color - light and searchlight varieties are capable of displaying the same aspects; the only difference is that the searchlight signals use a single globe for each head rather than three separate globes arranged vertically on each head.

The US system is speed based, unlike UK signalling which is route oriented; and the Trainz system makes use of some of the USA ‘limited’ speed aspects.

	The most common US signal protects a section of track where no diverging path is to be expected. Fig.4 depicts an absolute signal, it may not be passed at red. Fig.5 depicts an “automatic” signal; which can be identified by the presence of a number board. After bringing your train to a halt before an automatic signal at STOP, you may proceed into the block at a speed sufficiently low enough to stop within the visible distance ahead. An automatic signal should never be used to a protect junction, or entrance to single line as they do not provide absolute protection.
Fig.4		Fig.5

	On the approach to a section containing a diverging path such as a passing loop, you can find an automatic signal with two heads, as shown in Fig.6. This is the distant signal for the junction. Being another permissive signal as indicated by the presence of a numberboard, it may be passed at STOP. The “home” or “absolute” signal ahead which protects the junction may not be passed at STOP. It may have two or three heads, but the indications for use in Driver sessions are the same. The absolute signal with three lights as shown in Fig.7, is capable of displaying low speed aspects for entering occupied blocks during Scenarios.
Fig.6		Fig.7

SIGNAL PLACEMENT

Signal placement is very important for correct operation of the system. There are some rules to consider while signalling your map.

Firstly, and at ground level, the ideal situation for all trackside features is when all tracks are laid in the same direction. If you’re heading south for example with your new frontier, avoid moving ahead and laying backward toward the southbound track with northbound track.

Avoid placing signals at intervals shorter than braking distance considering the speed limit and the types of train that you operate. If you are using a 3-aspect system whereby you have only placed signals capable of displaying STOP, CAUTION and CLEAR; then you will need to allow distance on sighting a yellow signal to stop before the red signal ahead.

This is issue is particularly sensitive when planning signalling for AI traffic. Always allow suitable braking distance considering the locality and the type of traffic the route will see.

4-Aspect Systems

The QR and BR 4-aspect signals e.g. BR05, and the US multi-aspect signals e.g. USA_002, USA2_002 etc are capable of displaying the state of two blocks ahead. The sequence approaching a signal at STOP is as follows….

CLEAR / ADVANCED CAUTION / CAUTION / STOP

These aspects provide the driver with early warning of a red signal ahead, and in regions protected by these signals; it is generally possible to place signals at redu

Junction Levers

When placing a lever or point machine at a junction, ensure it is placed on the piece of track in rear the spline point where the track divides. The same rule should be observed when positioning signals, which protect a diverging path, and in fact they should be positioned in rear of the lever or point machine. Fig.8 depicts the lever incorrectly placed in advance of the spline point, on one of the diverging sections; see Fig.9 for correct lever placement. If you can move the lever beyond the diverging spline point, it is incorrectly placed. Your junction elements therefore need to appear in the correct order. Approaching a junction as the driver, you should first pass the signal, and then pass the lever, then the spline point where the divergence starts. The junction lever must be placed between the signal and the spline point at the start of the divergence. To toggle spline points in and out of view in trackside mode use Ctrl-O.
	Fig.8	Fig.9

Signalling Junctions

Trainz features simplified support for junction signalling; it is capable of displaying a route indication in for the next junction. This feature is not an exact parallel with the prototype.

Placing a signal with route feathers in rear of a junction will warn the driver of the state of the junction ahead. If the junction is set to the diverging path (which you essentially nominate that to be by choice of signal), a row of white lights will illuminate indicating the direction of divergence.

If the diverging path makes a further divergence and it is not protected by another signal, then the route feathers on the previous signal will not light unless the direction it is capable of displaying is set at both junctions. The route indicator will only light if the extreme path is set for the direction it can display over successive unprotected junctions.

This issue also applies to the US & SAR systems, expect the indication of diverging path is given by the relevant combination of colours rather than a row of white lights.

The US & SAR signals are not direction oriented in real life, however, when signalling junctions, the direction of the divergence must be considered. If you consider the route left to be the divergence, then a left – specific set up is required. The US and SAR signals for left divergence are the only signals with an L in the filename.

e.g.	USA_L001 for left divergence USA_001 for right divergence USA2_L001 for left divergence USA2_001 for right divergence SAR_L001 for left divergence SAR_001 for right divergence.

RH in the filename for QR & BR signals means that the signal is positioned to the right of the track. The QR and BR signals are visually route specific.

e.g.	QR02 for left divergence QR03 for right divergence

The following illustrations show typical signalling scenarios for protecting junctions as intended for use by the Trainz 1.3 signalling system. To avoid clutter, these show the signalling for one direction only, travelling from bottom upwards. The signals in the diagrams are labelled with their names as appearing in the menu.

USA - Diverging Path

Note the differences in the installation of signals protecting left and right divergence. While they look visually identical, they are programmed to respond to one direction only, and it’s therefore necessary to place the correct signal.

Fig.10

Note that not only on approach to a junction, but also where a multi-aspect signal protects the divergence entering the main line, the specific left or right - programmed signal is used.

e.g.	USA_02 where the track enters from the left USA_L02 where it enters from the right.

SAR - Diverging Path
While the US system differentiates between absolute and permissive signals by the use of number boards; the SAR system has lights staggered across the mast on permissive signals. Where a single aspect signal is used, a small marker lamp is fitted roughly half way up the mast; it’s position either side of the mast indicating the kind of signal. All lights to left of mast = absolute Lights staggered across mast = permissive.
Fig.11
Under the Trainz signalling system, only the permissive 003 signals are programmed to display “Reduce to Medium Speed”; but in terms of the logic, it is simply an ADVANCED CAUTION aspect, and therefore is displayed only when the absolute signal ahead is at CAUTION, and irrespective of whether the path is set to diverge.

BR & QR - Diverging Path
The BR and QR systems are covered in Fig.12 Below. The use of the approach signal BR07 is optional, a normal absolute signal can be substituted, particularly if you expect the area to be heavy with AI traffic.
Fig.12

Gantry Signals
	Another new feature of Trainz is the addition of gantry signals, which hang from overhead. They all display the normal STOP/CAUTION/PROCEED sequence. The gantry and the gantry signal are two separate objects, and they must be aligned manually with one another. A little trial and error will result in satisfactory placement. There a several new kinds of gantry signal included, some are spaced at intervals, which rely on the use of double track sections for correct placement. The gantry signals appear in Surveyor as signals suspended at height above the tracks with nothing apparently supporting them. Move them along the tracks with the Move tool for trackside objects.
Fig.13

Signalling Numbering
	All signals can be numbered for the purpose of Scenario control, and all except the US absolute signals now feature editable number boards. Change the numbers by using the ‘define name’ button in the Track Panel / Trackside Objects.
Fig.14

Guide to supported BR & QR ASPECTS…

Indication: STOP

Stop - Block is Occupied

CAUTION: Proceed with caution

Next signal is at STOP

CAUTION DIVERGING: Proceed with caution prepared to diverge.

Block is clear, path is set to diverge at the next junction; and the next signal is at STOP.

ADVANCED CAUTION: Proceed expecting caution at next signal.

Line clear two blocks ahead; the next signal is at caution.

PROCEED: Proceed

Block is clear next signal is at caution or clear

PROCEED: Proceed prepared to diverge at next junction.

Block is clear, path is set to diverge at the next junction; next signal is at caution or clear.

Guide to supported SAR ASPECTS…

Indication: STOP

Stop - Block is Occupied

Indication: STOP THEN PROCEED

Stop then proceed prepared to stop short of any obstruction.

CAUTION: Proceed with caution

Next signal is at STOP

CLEAR: proceed

Block is clear and next signal is at caution or clear for normal speed

CLEAR MEDIUM SPEED: Proceed at medium speed

Block is clear but suitable for medium speed only, and next signal is at caution or clear for medium or normal speed.

CAUTION MEDIUM SPEED: Proceed with caution

Block is clear but suitable for medium speed only, and next signal is at STOP.

REDUCE TO MEDIUM SPEED: Proceed prepared to pass next signal at medium speed.

Block is clear for normal speed; next signal is at caution or clear for medium speed.

Guide to supported USA ASPECTS…

Indication: STOP

Block is occupied

Indication: STOP THEN PROCEED

Stop, then proceed at Restricted Speed until the entire train has passed a more favourable signal.

Indication: APPROACH

Next signal is at STOP. Proceed prepared to stop at the next signal. Trains exceeding Medium Speed must begin reduction to Medium Speed as soon as the engine passes the Approach signal.

Indication: CLEAR

Proceed not exceeding Normal Speed.

Indication: LIMITED CLEAR

Proceed at Limited Speed until entire train clears all interlocking then proceed at Normal Speed.

Indication: APPROACH LIMITED

Proceed approaching the next signal at Limited Speed.

Indication: MEDIUM APPROACH

Proceed prepared to stop at the next signal. Trains exceeding Medium Speed must begin reduction to Medium Speed as soon as the Medium Approach Signal is clearly visible.

GLOSSARY
ABSOLUTE SIGNAL	A signal that must never be passed when displaying STOP
AI	Artificial Intelligence
ASPECT	A command displayed by a signal i.e. STOP
DISTANT SIGNAL	A signal that warns of approach to an absolute signal ahead.
FACING POINTS	A junction or turnout where the main line diverges before the driver. It may be a branch line, passing loop, entrance to a yard etc. A turnout ahead at which your route may diverge.
FEATHERS	A row of white lights positioned on an extra head above the normal signal aspects, which indicate the state of a junction ahead.
GANTRY	A small bridge over multiple tracks supporting overhead signals.
HOME SIGNAL	An absolute signal.
IN ADVANCE	A home signal is said to be ‘in advance’ of it’s distant signal; i.e. it is up ahead.
IN REAR	A distant signal is said to be ‘in rear’ of it’s home signal. The fist signal you encounter in a station’s installation for example, is considered the rear.
INTERLOCKING	An arrangement of appliances such as signals and turnouts so interconnected that their movements affect the state of each other.
PERMISSIVE SIGNAL	A signal that can always be passed. The USA & SAR STOP then PROCEED indications of automatic signals are permissive in that they may be passed at red after bringing the train to a halt. The UK and QR approach signals are also permissive as they can always be passed. These signals are never used to protect junctions.

© 2002 Auran

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