Purpose of these Automatic Signalling Rules is to prescribe the Safe working Rules which support the application of Automatic Signalling.
The Automatic Signalling system uses continuous track-circuiting and/or axle counters to:
- detect the presence of rail traffic
- prevent following and opposing rail traffic entries into occupied
sections of track
- provide advanced warning of the status of the next signal.
The Automatic Signalling system allows trains to travel safely over:
- single lines, for movements in both directions
- multiple lines, for movements in either direction or one direction only.
Entry to and exit from sections of line can be governed by Absolute or
Permissive signals or Block Entry and Station Entry boards.
Automatic Signalling area consists of four key features (refer Fig.3):
- Block Sections
- Intermediate Sections
- Switch Locked Sidings
- Interlocked Stations.
If the Automatic Signalling system fails, or is otherwise compromised (e.g. disabled train) a special method of safe working, as outlined in these Rules, will be applied.
Separate rules apply for the Single Line Automatic Signalling System (SLAS) governing operations on the Midland Line (South Island)
For the purpose of these Safe working Rules the following definitions apply:
A signal that must not be passed at "Stop" without the authority of Train
Control or the Signaller as provided for in these safe working rules.
Absolute Signals are Stop and Stay signals.
Block Entry Board
Provided in Multi line areas where a signal is not available and defines a boundary for entry into a Block Section for wrong line running. These boards are absolute and may only be passed with the appropriate written authority from Train Control.
A Block Section is a single section of line between two adjoining interlocked stations in either single or multiple line area
The Block Section will permit movements in either both directions or one direction only.
Entrance to a block section is governed by a Departure or Starting signal or Block Entry boards.
These are Absolute signals.
Departure Signals control entry to a Block section where movements are signalled in both directions.
Starting Signals control entry to a Block section where movements are signalled in one direction only.
Block Section Entry Signal Identification in Multiple Line areas
- In multiple line areas Departure (fig #1) and Starting (fig #2) signals will be identified by the Signal marker board showing
"Depart" or "Start".
Any portion of a Block Section divided into two or more intermediate sections.
Entrance to subsequent intermediate sections is governed by an Intermediate signal. These signals can be Absolute or Permissive signals.
A station or portion of a station with automatic signalling provided to prevent conflicting movements.
Entry to an Interlocked Station is governed by Home signals or, where provided, Outer Home signals or Station Entry boards.
These are Absolute signals.
In multiple lines areas, the signals at some Interlocked Stations are Absolute Signals (Stop and Stay) fitted with an "A" light. These signals are manually controlled when the station is "Switched In" ("A" light not illuminated) and operate automatically when the station is "Switched Out" ("A" light illuminated).
These signals are Absolute signals when the station is "Switched In" and Permissive signals when the station is "Switched Out".
Where there is more than one main line between two stations, these are known as "Multi Lines".
The running direction of these lines is shown on S&I diagrams
The Locomotive Engineer, Remote Control Operator or Mobile Track Maintenance Vehicle (MTMV) Operator who is in charge of the train or machine group.
This meaning is specific to this document; not to be confused with National Rail System Standards (NRSS) or The Railways Act 2005
A signal that is normally controlled by the passage of rail traffic and may be
passed without the authority of a Train Controller or Signaller as provided for in these safe working rules.
Permissive Signals are Stop and Proceed signals or Stop and Stay signals with "A" lights illuminated.
A speed that allows rail traffic to stop short of an obstruction within half the distance of clear line that is visible ahead, taking into consideration the physical characteristics of the track being traversed and the environmental conditions. Not to exceed 40 km/h.
Safe Working Authority
A Safe Working Authority (SWA) form may be used to authorise rail traffic movements not otherwise permitted under the normal system of safeworking.
The person who directly controls signals at an Interlocked Station.
Station Entry Board
Provided in Multi line areas where a signal is not available and defines a
boundary for entry into an Interlocked Station for wrong line running. These boards are absolute and may only be passed with the verbal authority from the Signaller
Includes all lines within the outer most signals, station entry boards or points on each line controlled by the Signaller for the station or as otherwise defined on S&I diagrams
Switch locked Sidings
Sidings within an Interlocked Station or Block Section fitted with points that
can only be reversed for the siding after an electric lock has been released.
Wrong Line Running
Train movements running in the opposite direction in a Block Section where
the Automatic Signalling system is designed to allow train movements in one direction only.