SIGNALS Flashcards
What are the 6 classes of 2 position signals?
- Home
- Dwarf
- Disc
- Distant
- Siding Dwarf
- Calling on
What are the 2 main purposes of signal systems?
- Communicate to the driver the state of the line ahead
- Give the driver authority to proceed
What are the two types of two position signals?
- Light Type
- Disc Type
What signal is both a class and a type?
Disc Signal
What do two position Home signals protect (and positioned at)?
Stations
Signal Boxes
Sidings
Level Crossings
Junctions
What two aspects can the two position Home system show?
Red - Stop
Green - Proceed
When a two position home signal is showing proceed, are the points set and the line clear ahead?
Yes the points and line are clear.
What does a proceed aspect on a two position home signal not show?
Does not indicate if next signal is at proceed.
Driver should be prepared to stop at next signal and assume it’s at stop.
What 2 aspects do distant signals display?
- Caution
- Proceed
Why would a distant signal be at caution?
- A train is in the section
- An obstruction on the line
- A signal in the block is at danger
When coming across a distant signal at caution, can it tell you which signal is at stop?
No, it only indicates that a signal in the block is at stop
What does a call on signal mean?
A train can enter into an occupied section, past the stop aspect.
How would a driver pass a calling on signal showing proceed?
Advance cautiously past the signal and be able to stop short of any obstruction
If the home signal is clear (green) AND bottom light is on, can you proceed?
No, it would be treated as an irregular signal aspect. Treat as both signals are at their safest aspect.
What are disc signals used to control? (train movements)
- Running line to running line
- Running line to siding
- Siding to siding
- Siding to running line
What 2 aspects do disc signals display?
Stop and Proceed
What does a disc signal tell us? (PTSN)
P - Points are set
T - Track ahead may be occupied
S - Speed is reduced speed cautiously
N - Next signal is unknown so be prepared to stop
When a disc signal is at proceed, what must you be aware of?
The line may be occupied or obstructed
What is the max speed at a siding?
15km/h
What is the max speed at points? (running line to running line)
40km/h
How can a disc signal show an aspect at night?
It has a red or green light depending on if it reads stop or proceed
How do you read a set of 4 disc signals on one post?
Top to bottom, left to right
1-3
2-4
What does a two position dwarf signal control?
- Running line to running line
- Running line to siding
- Siding to siding
- Siding to running line
What are the two different types of two position dwarf signals?
Standard 2 position dwarf signal
And a siding Dwarf (fitted on same past as home signal)
What aspects can a dwarf signal display?
Stop - Red/Blue/Purple
Proceed - Green or Yellow (for a siding dwarf)
How can a siding dwarf and a call on signal be distinguished?
Call on is just the light
Siding dwarf has the light AND a siding sign
If a two position dwarf signal is at proceed, is the line clear?
No, the track ahead may be occupied
What happens when a track circuit is broken?
The signal reverts to it’s fail safe aspect (stop)
What are 3 things that can break a tracks circuit?
- Damaged track
- Obstructed track
- Occupied by another train
How does an axle counter work?
It counts how many axles enter a block and makes sure it matches with how many axles leave the block. It feeds this information to the signals to show the block is occupied or clear.
What light colours can be shown by a 3 position signals?
Red - stop/reference light
Yellow - warning
Green - clear
What information can a 3 position signals provide?
Points - set or not set
Track section ahead - clear or occupied
Speed - normal/medium track speed
Next Signal - whether next signal aspect is proceed or stop
What is the top light (A light) referring to in a 3 position signal set?
The A light refers to normal speed
What is the bottom light (B light) referring to in a 3 position signal set?
Medium speed aspect
What signal class can have a C Light or Low speed aspect?
Home signal
How can you tell a home signal and an automatic signal apart?
Home has two lights vertically
Automatic has the two lights staggered
What are the three classes of 3 position signals?
Home
Automatic
Dwarf
Why is it important to know the difference between the classes of signals?
Rules and instructions vary depending on class and location of signal
Where are 3 position signals fixed at and protecting?
Stations
Signal boxes
Sidings
Level crossings
Junctions
Which classes of 3 position signal is usually controlled?
Home signals and Dwarf signals
If you need to pass a home signal that is uncontrolled, who would you contact for permission?
Signaller/Area Controller (Signal Control Panel)
What is the primary purpose of automatic signals?
Expedite the passage of trains by dividing long sections of track into shorter sections.
Can automatic signals at stop be passed?
Yes, only if you follow Rule 1, Section 3
Which signals are classified as absolute or permissive?
Absolute - Home, Dwarf, Disc
Permissive - Automatic
How many aspects can a 3 position signal show?
6 with A & B lights
7 with A, B & C lights (only on home)
What aspect is this signal showing?
Clear Normal Speed
For a Clear Normal Speed aspect, what does the signal tell us? (PTSN)
P - Points are set
T - Track is clear
S - Speed is track speed
N - Next signal will show proceed
What aspect is shown on this signal?
Normal Speed Warning
What does a Normal Speed Warning tell us? (PTSN)
P - Points are set
T - Track is clear
S - Speed is track speed, but prepare to stop at next signal
N - Next signal will be at stop
This signal is Reduce to Medium, what speed is medium?
40km/h
What does a reduce to medium signal tell us? (PTSN)
P - Points are set
T - Track is clear (till next signal)
S - Track speed but prepare to reduce to medium by next signal
N - Next signal will be at medium aspect
What does a Red A light over a Green B light signify? (Name + PTSN)
Clear Medium Speed
P - Points are set
T - Track is clear
S - Speed is medium (40km/h)
N - Next signal will be a proceed
What is the name of this aspect and what does it tell us? (PTSN)
Medium Speed Warning
P - Points are set
T - Track is clear
S - Speed is medium (40km/h), prepare to stop before next signal
N - Next signal is at stop
What do 2 red lights on a signal mean?
Stop!
Points may not be set, track may be occupied.
When stopped at danger aspect, what should you do with your reverser?
Set to neutral or off
Marker lights to white
What is the name of this aspect and it’s PTSN?
Low Speed Caution
P - Points are set
T - Track ahead may be occupied
S - Speed is low speed 15km/h, be ready to stop short of any obstruction
N - Don’t know next signal aspect, assume next one is at safest position
What 2 locations can a low speed signal take you to?
- A siding
- Main line track/running line to running line (eg. to a station to couple with another train)
When can a Low Speed Caution never be used?
For train movements into a bi-directional portion of track
What signal aspects come before a stop aspect?
Reduce to Medium (sometimes) then Normal Speed Warning or Medium Speed Warning
What does an illuminated 65 or 80 mean on a home or automatic signal?
High speed points ahead, reduce to 65 or 80 based on what is shown.
What does an illuminated red A on a 3 position home signal mean?
Home signal has been switched to automatic as is to be treated as an automatic signal (only visible on a signal at stop)
If a signaller is operating points and signals, the signal box is referred to as?
Switched In
If the signaller is off duty, what is the signal box referred to as?
Switched out
When the signal box is switched out and running by the passage of trains, what is the mode called?
Fleeting Mode
What 3 aspects does a three position dwarf show?
Stop
Low speed caution
Clear low speed
What is the primary purpose of Banner Indicators?
They indicate the aspect of the signal ahead when a clear view of the signal cannot be obtained
Banner Indicators are not….?
They are not:
Fixed signals
Considered to be signals in advance
What signal is being repeated on the Banner Indicator when it shows 2 horizontal lines?
Stop
What aspect is shown on the Banner Indicator?
Normal Speed Warning
What signal is the Banner Indicator showing?
Reduce to medium
What aspect is the Banner Indicator showing?
Stop
Who do you report a faulty Banner Indicator to?
Train Control @ Metrol
When are hand signals used?
- To stop trains in an emergency
- Control shunting movements
- To communicate specific instructions
How are hand signals made?
Hands, flags, paddles and lamps/torches
If you lose sight of your hand signaller or the hand signal is unclear, what should you do?
Stop your train Immediately and make enquiries
When are stop/danger hand signals used?
- In an emergency to warn of danger
- By station staff if they need to stop you leaving due to an emergency
- During shunting movements
- Given by a driver when protecting a disabled train
- Given by a hand signaller when a defective signal cannot be secured at stop
What flag is used for Stop?
Red Flag
How is stop/danger hand signalled at night?
A steady red light or any coloured light waved violently
Or a red light on a dispatch paddle
What is the hand signal for stop during the day?
Arms above the head with elbows bent at 90 degrees
How do you hand signal ‘Move Backwards’ during the day? (Move towards hand signaller)
Wave arm inwardly across the body
How do you hand signal ‘Move Backwards’ during at night? (Move towards hand signaller)
Wave a white light slowly from side to side across the body
How do you hand signal ‘Move Backwards’ during at night? (Move towards hand signaller)
Wave a white light slowly from side to side across the body
How do you tell the driver to (insert instruction) move slowly when hand signally at night and day?
Day - one arm raised above the head, other hand signalling movement
Night - green light performing movement instead of white
How do you hand signal ‘Move Forward’ during the day and at night? (Move away from hand signaller)
Day - Wave arm outwardly in a circle from the body
Night - wave a white light slowly up and down
How do you hand signal ‘Move Forward’ during the day and at night? (Move away from hand signaller)
Day - Wave arm outwardly in a circle from the body
Night - wave a white light slowly up and down
How do you hand signal ‘ease up’ by day and night? (Used during coupling)
Day - Raise both hands overhead, bringing fingertips together and then seperate
Night - wave a GREEN light slowly from side to side across the body
Immediately prior to coupling, what hand signal must be given? (To anticipate coupling)
Stop
How is the alright hand signal shown during the day and at night?
Day - Hold arm in horizontal position or a white flag
Night - white light held steadily or a dispatch paddle with a white light
Does an All Right hand signal mean proceed?
No, you must obey the signal aspect
What hand signal means Proceed or All Clear? (Day and night)
Day - Green Flags
Night - Green light held steady
What are 4 reasons why a Proceed/All Clear hand signal would be used?
- To authorise a driver past a fixed signal when it’s out of order (after receiving correct authority)
- To pass over certain points not interlocked with signals
- To caution a driver entering an occupied line where no low speed signal is provided (after stopping and giving driver verbal warning)
- Displayed by track force protection by lookout or inner flag person
What does ABS stand for?
A - Automatic
B - Block
S - Signalling
What are the two variances of ABS?
- Double Line - designated up and down lines
- Single Line - Bi-directional
What is a block and a track section?
Block - Home signal to home signal
Track section - from automatic signal to automatic signal between a block
What are the two objects of ABS?
- Allows multiple trains to proceed in the same direction by limiting them to 1 train per track section at one time.
- On bi-directional ABS only one train can be in a whole block section when trains are running in opposing directions.
What defines a station limit?
A station limit is a portion of line that is under the direct control of a signaller and protected by the positioning of home signals.
How do you tell what area is the station limits for ABS?
From the first home signal to the first automatic automatic signal at advance
How is a signal diagram read?
A signal diagram is read like a map
What does ATC stand for?
A - Automatic and
T - Track
C - Control
What are the two objects of the ATC system?
- When 2 or more trains are proceeding in the same direction, the object is to prevent more than one train being on a track section at one time.
- When trains are proceeding in opposing directions through a single line section, the object is to prevent more than one train entering the single line section at a time.
How do departure signals protect the signal line track from opposing trains?
Once a departure signals changes to proceed the opposing departure signals is secured/sleeved to stop
At remote controlled crossing loops during period of signal failures, who might be asked to operate the dual control point machines?
A driver may be asked (by signaller or TC) to operate the points
What are the station limits for ATC?
From home arrival signal to arrival signal
When in a ATC station limit, who can give drivers instructions to move?
The signaller can give the driver instructions to move
What is the single line section?
Bi directional portion of line between two crossing loops
What signals control the entrance into the single line section?
Departure signals and a dwarf signal in some locations (when entering from a siding)
How can a home arrival signal be identified?
All home arrival signals have a low speed aspect (C Light)
When a home departure signal shows clear medium speed (ATC) when does the speed restriction end?
Once the train clears the points protected by the signals
What are the 3 main types of route indicators?
- Arrow
- Letter
- Feather
What are the 3 sub-types of the Letter type?
- Dual Gauge route indicators
- Illuminated letters
- Theatre type
What are the 2 sub-types of Arrow types?
- Painted arrows
- Illuminated arrows
What else can indicate a route is set? (Outside the main types)
Signal aspects can also indicate route is set
What letters are used on dual Gauge indicators?
V - Victorian Broad Gauge (5ft)
S - Standard Gauge (4ft)
Where is the only feather light indicator found on the MTM network?
Platform 1 at Richmond Station
How can signal aspects indicate a route?
Points must be passed at 40km/h (unless otherwise signed) so a medium speed aspect would mean the train is diverging and a clear normal speed means the train is proceeding ahead.
What route indicators is this?
Arrow Type - Painted arrows
What route indicators type and sub-type is pictured?
Arrow Type - Illuminated arrows
What route indicators type and sub-type is shown?
Letter Type - Illuminated Letters