Signals Flashcards
What is the Type of 3 Position Signal?
Light
What are the Classes of 3 Position Signals?
Home
Automatic
Dwarf
What are the Aspects of 3 Position Signals?
Clear Normal Speed
Normal Speed Warning
Clear Medium Speed
Medium Speed Warning
Reduce to Medium
Stop
Low Speed Caution
What are the 4 Points for Every Aspect?
PTSN
-Points
-Track Ahead
-Speed
-Next Signal
What is a Clear Normal Speed Aspect?
P - Points are set
T - Track is clear
S - Track Speed
N - Proceed
What is a Normal Speed Warning Aspect?
P - Points are set
T - Track is clear
S - Track speed
N - Stop
What is a Medium Speed Aspect?
P - Points are set
T - Track is clear
S - Track speed
N - Medium aspect
What is a Clear Medium Speed Aspect?
P - Points are set
T - Track is clear
S - 40km/h max
N - Proceed
What is a Medium Speed Warning Aspect?
P - Points are set
T - Track is clear
S - 40km/h max
N - Stop
What is a Stop Aspect?
P - Unknown
T - May be occupied
S - Do NOT proceed
N - Unknown
What is a Low Speed Caution Aspect?
P - Points are set
T - May be occupied
S - 15km/h
N - Prepare to stop if next signal is at stop
What is an illuminated “A” on a Home Signal mean?
It is now treated as Automatic, because:
-The signaller is no longer operating the panel
-The signaller has gone home
To check whether the points are set, what do you need?
Reactive Track Access Form, unless you can observe from a Position of Safety
Can you pass an illuminated “A” signal if you can see no danger?
Yes, under Rule 1, Section 3
Can you get an illuminated “A” if the signal is at Proceed?
No, because the signal is operating normally.
Are Banner Indicators Signals?
No, and you cannot accept them as signals. They are purely indicators.
When do Banner Indicators appear?
-When the upcoming signal is obstructed by infrastructure
-Cannot see upcoming signals due to the curve of the railway
-Viaducts
What must the Driver do if the Indicator fails?
-Treat as defective
-Presume that the next signal is displaying its safest aspect, STOP
-Contact Train Control
What are Repeated Signals?
Used to give advanced warning of a 3 Position Signal Aspect, when leaving a 2 Position Signalled Area.
What can a Repeated Signal Display?
Warning
Proceed
Reduce to Medium
What does a Repeated Warning Signal Aspect look like?
2 Straight Yellows
What does a Repeated Proceed Signal Aspect look like?
Green over Yellow
What does a Repeated Reduce to Medium Aspect look like?
-Works in the same manner as other 3 Position Signals.
-An illuminated 65 or 80 can be fitted to determine the upcoming track speed.
What is Axle Counter Technology?
-Uses sensors located at defined points
-When the train passes an Axle Counter, it records the number of axles passing that point, informing the signal. If the numbers match as the train passes, it alters the signals from behind to necessary signal.