Glossary of Terms


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Lamp Proving
A system that ensures the required lamp(s) are lit, for example, by measuring the current drawn by the lamp(s).

Overseas
Disciplines: Train Control
Lamp Repeater
Repeater, the indications of which are given by lamps which are either lit or extinguished.

Preferred
Disciplines: Electrical
Landmark
Provided instead of a distant signal at places where it is necessary, in all cases, for trains to approach with caution.

Regional
Disciplines: Train Control
Lateral
The direction across the track, parallel to the line joining the top of the rail heads.

Preferred
Disciplines: ALL Disciplines
Lateral Track Shifting Force
The lateral force exerted by each wheelset, tending to shift the rails and sleepers laterally in the ballast.

Preferred
Disciplines: Rolling Stock, Infrastructure
Lateral Wheel To Rail Force
The lateral force between an individual wheel and the rail including components at the wheel tread and/or flange, depending on the contact conditions.

Preferred
Disciplines: Rolling Stock, Infrastructure
LB
Line Blocked


Disciplines:
LC
Line Clear


Disciplines:
LCL
Less than Container Load


Disciplines:
LDU
Locomotive Display Unit


Disciplines:
Lead Investigator
A person appointed by the responsible authority, who is charged with the responsibility for the organisation, conduct and control of the investigation and for the production of the final investigation report, generally referred to in this Standard as 'the investigator'.

Preferred
Disciplines: ALL Disciplines
Lead Rail
The rail in a crossingwork assembly between the heel of a set of points and the adjoining crossing.

Preferred
Disciplines: Infrastructure
Leaky Co-axial Cable
A special co-axial cable which radiates radio transmission signals continuously along its length.

Preferred
Disciplines: Electrical
LED
Light Emitting Diode signal


Disciplines:
LED Signal
Abbreviated term for 'light emitting diode signal'.

Overseas
Disciplines: Train Control
Less Than Container Load (LCL)
Many freight forwarders consolidate consignments which are less than a full container load into full containers for transport by rail. (Historical usage was 'less than car load'.)

Legacy
Disciplines: Rolling Stock, Operations
Level Crossing
A location where the railway line and a road or pedestrian walkway cross paths on the same level.

Preferred
Disciplines: ALL Disciplines
Level Crossing Accident
A collision involving a train with either a road vehicle or a person at a level crossing, including a pedestrian crossing.

Preferred
Disciplines: ALL Disciplines
Level Crossing Test
This is an operational test of level crossing control circuits to check for adequate protection time, time of operation, etc. The checks are made by comparison with track plans, control tables etc.

Regional
Disciplines: Train Control
Lever (or Switch) Plate
An identification plate fixed to a lever (or adjacent to a switch), describing the lever / switch function together with the order of pulling details.

Regional
Disciplines: Train Control
Lever Bands
Contacts housed in a circuit controller that is associated with a lever.

Overseas
Disciplines: Train Control
Lever Frame
A frame in which the levers working signals and points in an area are mounted together and interlocked as required by the layout.

Regional
Disciplines: Train Control
Lever Lock
An electro-mechanical mechanism fitted to hold (and release) the lever in a predetermined position. May be combined with a circuit controller.

Regional
Disciplines: Train Control
Lever Rod
The rod connecting the point lever and crank.

Preferred
Disciplines: Infrastructure, Electrical
Lever Sleeve
Piece of equipment placed over a lever as a blocking facility to physically prevent it from being operated.

Regional
Disciplines: Train Control
Lever Stick
A circuit in track circuited areas, which insures that a signal lever is returned by the signaller to the normal or normal indication position after each train movement before the signal can be again cleared.

Regional
Disciplines: Train Control
Lift (container)
A lift is the picking up and placing of a container either on or off a wagon.

Preferred
Disciplines: Operations
Lift (track)
To raise and pack the track to the required design level.

Preferred
Disciplines: Infrastructure
Lifting Bar
When this type of bar is operated, it rises to rail surface level and falls again once it is in position. If a train is passing over the bar, the wheels prevent the bar from lifting and consequently prevent the associated points from being unlocked or operated.

Regional
Disciplines: Operations
Light Emitting Diode (LED) Signal
A colour light signal that uses light emitting diode technology in place of incandescent lamps and coloured filters.
LED signals can be arranged to combine the Red, Yellow and Green Aspects into one aperture to generate the appropriate aspect.

Preferred
Disciplines: Train Control
Light Engine
See Light Locomotive.

Alternative
Disciplines: Rolling Stock
Light In Colour Light Aspect
Luminous indication constituting the whole or part of a signal.

Preferred
Disciplines: Electrical
Light Locomotive
One or more locomotives coupled without vehicles.

Preferred
Disciplines: Rolling Stock
Light Rail Network
A passenger-carrying railway system operating with trams or other similar shorter length, lower speed and lower axle-load self-propelled vehicles. Typically used in urban areas and often having a shared right-of-way with road traffic.

Preferred
Disciplines: Rolling Stock
Light Rail Stop
Any place designated for the picking up or setting down of passengers on a light rail route.

Preferred
Disciplines: ALL Disciplines
Light Rail Vehicle
A vehicle used on a light rail system.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Light Signals
Display coloured lights during day and night.

Non-preferred
Disciplines: Train Control
Refer 'colour light signals'
Alternative
Disciplines: Train Control
Light Track Equipment
Any small track maintenance machine or item of equipment that, under normal conditions, can be removed from the track by two workers. A lightly loaded road-rail vehicle that can be safely removed from the track may be regarded as light track equipment.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Light Track Vehicle
A track vehicle, generally a high-rail vehicle, which the Rail Infrastructure Manager has specified as light.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Light Unit
Assembly inside a sealed casing of all the parts (lamp, optical apparatus, coloured glass, terminals etc) necessary to exhibit a light's aspect.

Preferred
Disciplines: Electrical
Light, Battery Powered Tool Or Device
An internally powered tool or device that can be easily carried by one person and can be immediately removed from the track.

Preferred
Disciplines: ALL Disciplines, Infrastructure
Light, Non-powered Hand Tool
A tool that can be carried and easily removed by one person and is not powered by compressed air, gas, electricity, hydraulics, explosive charge or internal combustion engine.

Preferred
Disciplines: ALL Disciplines, Infrastructure
Light, Powered Hand Tool
An internally powered tool that can be carried easily by one person, without mechanical assistance.

Preferred
Disciplines: ALL Disciplines, Infrastructure
Likeness
means the semblance or appearance of something

Preferred
Disciplines: ALL Disciplines
Limit Of Authority
The limit of Authority may be defined by a sign, a signal capable of displaying a STOP indication, or a specific kilometrage point on a line.
It defines the location to which rail traffic may travel under a Proceed Authority or the limits of a work on track authority.

Preferred
Disciplines: ALL Disciplines
Limit Of Authority Overrun
Passing the end of movement authority. The conventional terminology for an overrun is a signal passed at danger (SPAD).

Preferred
Disciplines: Train Control, Operations
Limit Of Shunt Board
A notice board on a running line indicating a point beyond which shunting movements must not be made.

Regional
Disciplines: Train Control, Operations
Limit Of Shunt Indicator (LOS)
A special type of position light signal or sign to terminate a shunting movement along a line in the wrong direction.

Overseas
Disciplines: Train Control
Line
Horizontal alignment of the rails. Line is generally measured using the offset at a defined point along a chord of defined length. For vertical alignment see top.

Preferred
Disciplines: Infrastructure
Line Blocked (LB)
The normal state of a block section when no permission has been given for a train to enter it.

Overseas
Disciplines: Train Control
Line Capacity
For a given section of line, the practical maximum number of trains per hour permitted by the signalling system.

Preferred
Disciplines: ALL Disciplines
Line Clear (LC)
The state of the block section after a train has been accepted but before it has entered the block section.

Overseas
Disciplines: Train Control
Line Clear Release
The signaller can only pull the lever for the section signal if line clear is obtained from the box ahead. The lever is released either for one pull or one train.

Overseas
Disciplines: Train Control
Line Haul
The term used to describe the movement of trains outside of terminals and yards with shunting employees.

Regional
Disciplines: Operations
Line Pole
The poles in an overhead line route which carry the cross-arms supporting the line wires or cables.

Regional
Disciplines: Electrical
Line Relay
A relay receiving its operating energy through conductors of which the track rails form no part.

Regional
Disciplines: Electrical
Line Wires
Electrical circuit single conductor wires or cables erected on an overhead line route.

Regional
Disciplines: Electrical
Lineside Indicator
A visual display device at or near the lineside that provides information relating to the operation of a train. An indicator may be provided in conjunction with a signal to qualify or amplify the instruction conveyed by the signal.

Regional
Disciplines: Train Control, Operations
Lining
The process of establishing the track to the design vertical and horizontal alignment for tangents and curves.

Preferred
Disciplines: Infrastructure
Lit
The internal illumination of signalling equipment.

Preferred
Disciplines: Train Control
Livery
Rolling stock exterior colour scheme and markings.

Preferred
Disciplines: Rolling Stock
Livestock Incident
Incident involving an animal(s) large enough to damage rail traffic

Preferred
Disciplines: ALL Disciplines
Loading / Unloading Indicators
Indicators that relay movement instructions to drivers when controlling trains in sidings.

Overseas
Disciplines: Train Control, Operations
Loading Gauge
The device used to ascertain whether a load on a vehicle exceeds any height or width restrictions imposed over the line on which the loading is to travel. This is necessary because of clearances of structures, overhead bridges and tunnels, etc. Smaller than the structure gauge.

Preferred
Disciplines: Infrastructure
Loading Outline
An outline drawing or specification that describes the maximum permissible dimensions and shape of loading for transit over a nominated route.

Preferred
Disciplines: Rolling Stock
Local Control Facility
An interlocking facility that may be switched to and from local control, but is capable of being switched to remote control.
Local control facilities may include local control panels, key operated switches, or other equipment.

Preferred
Disciplines: ALL Disciplines, Train Control
Local Earth
Portable appliance for establishing electrical connection between de-energised overhead traction wiring equipment and traction earth.

Preferred
Disciplines: Electrical
Local Possession
Possessions transfer control of a section of track from the train control system to a separate body for purposes such as major track repair or reconstruction. Trains other than those under the control of the separate body are denied access to the tracks.

Non-preferred
Disciplines: ALL Disciplines
Refer Local Possession Authority
Alternative
Disciplines: ALL Disciplines
Local Possession Authority
An authority that closes a defined portion of track for a specified period.

Preferred
Disciplines: Train Control, Infrastructure
Locally Controlled Station
A block station where the switches and signals are controlled from a panel in the station building, or interlocking frame in a signal cabin, at the block station.

Regional
Disciplines: Train Control
Location
A place in the Network with a designated name, identification number, or signaling reference.

Preferred
Disciplines: ALL Disciplines
Location (cases)
One or more signalling lineside apparatus housings at a particular site and the equipment contained therein.

Overseas
Disciplines: Train Control
Location Ahead Sign
A sign marking the approach to a location and the location's recognition by its designated name.

Regional
Disciplines: Operations
Lock Circuit Controller
Electric circuit controller, the position of which depends on that of the point lock.

Preferred
Disciplines: Electrical
Lock Drop Contact
A proving contact fitted to a gravity operated electric lock. The contact is closed when the lock is in its locking position.

Regional
Disciplines: Electrical
Lock Proving
Checking the position of a point lock.

Preferred
Disciplines: Electrical
Lock Rod
A bar or rod connecting the point switches to which the facing point lock is attached or on which the facing point lock operates. Usually placed as close as possible to the tip of the switch.

Regional
Disciplines: Infrastructure
Lock Slide
The part of the clamp lock point mechanism which unlocks, moves and relocks the switches.

Overseas
Disciplines: Train Control, Infrastructure
Lock Spike
Refer to Springspike.

Alternative
Disciplines: Infrastructure
Related Term: Springspike
Lock Stretcher
A stretcher bar that is secured by a facing point lock.

Overseas
Disciplines: Infrastructure, Train Control
Locked
The state of any signalling function or item of equipment when it is conditionally or unconditionally prevented from changing state or position by other parts of the signalling system.

Overseas
Disciplines: Train Control
Locking Bar
A fouling bar, provided for mechanically worked facing points, that acts in conjunction with the facing point lock, preventing the unlocking of the points during the passage of a train. It has generally been superseded by more modern forms of train detection.

Legacy
Disciplines: Infrastructure
Locking Chart
A drawing showing in graphical form, the layout of mechanical locking for a lever frame.

Overseas
Disciplines: Train Control
Locking Dog
A steel block attached to a locking bar or tappet of an interlocking machine, by means of which locking between levers is accomplished.

Regional
Disciplines: Infrastructure, Train Control
Locking Level
The interlocking level where controls between signalling functions are required to be satisfied before a route can be set.

Overseas
Disciplines: Train Control
Locking Level Release
Controls that are required to be satisfied before the locking on a route or a section of a route is released. Controls on conflicting routes are released by the train clearing track sections. If required, controls on opposing routes are released by the train timed to a stand on an appropriate track section.

Overseas
Disciplines: Train Control
Refer to Route Locking.
Alternative
Disciplines: Train Control
Related Term: Route Locking
Lockout
A system which allows a person requiring access to the track to provide personal protection by restricting or preventing the signalling of trains.

Overseas
Disciplines: Train Control
Locomotive
Self-propelled, non-passenger-carrying railway vehicles used for hauling or propelling other (typically freight or passenger) rolling stock.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Locomotive Display Unit (LDU)
On-board display unit on locomotives used in Section Authority System.

Preferred
Disciplines: Operations, Train Control
Locomotive Rolling Stock
Refer Locomotive.

Preferred
Disciplines: Rolling Stock
Long Route
A route combining one or more other routes.

Regional
Disciplines: Train Control, Operations
Long Section Token
A type of token covering more than one single line section, usually in radio electronic token block areas.

Regional
Disciplines: Train Control
Long Train
A freight train of 800m or more in length.

Preferred
Disciplines: Rolling Stock
Long Welded Rail
Track where the rail is welded into lengths between 110 m and 300 m, with the rail lengths joined by fishplated joints. Some thermal expansion is provided for at the joints.

Preferred
Disciplines: Infrastructure
Lookout
A Competent Worker responsible for keeping watch for approaching rail traffic, and for warning other workers to stand clear of the line before the rail traffic arrives.

Preferred
Disciplines: ALL Disciplines
Lookout Working
A safety measure used by Competent Workers to carry out work on track without a formally issued work on track authority.

Preferred
Disciplines: ALL Disciplines

Alternative
Disciplines: ALL Disciplines, Operations
Related Term: Balloon Loop, Crossing Loop or Refuge Loop
LOS
Limit Of Shunt


Disciplines:
Abbreviated term for 'limit of shunt indicator'.
Alternative
Disciplines: Train Control
Louvre Car (or Louvre Wagon)
A box wagon in which the wall panels include louvres or similar devices for ventilation.

Regional
Disciplines: Rolling Stock
Low Risk Failure
A wrong side failure where another part of the signalling system provides an acceptable level of protection.

Non-preferred
Disciplines: Train Control
Refer Wrong Side Failure.
Alternative
Disciplines: Train Control
Low Speed (indication) Signal
A signal indication consisting of a small green light fixed below the 'stop' indication on a running signal. The low speed indication is provided to facilitate working where closer headway is desired for following trains and permits a train to approach and pass the signal at a restricted speed.

Regional
Disciplines: Train Control
Low Visibility
Any condition that does not allow Competent Workers to view the distance required to work safely.

Preferred
Disciplines: ALL Disciplines
Lower Quadrant
A term applied to a semaphore signal whose clear position is designated by the arm below horizontal.

Regional
Disciplines: Train Control
LPA
Local Possession Authority


Disciplines:
Luminance factor
Ratio of luninance level of a surface to that of an ideal white diffusing surface (ref. AS/NZS 1906.4)

Preferred
Disciplines: Rolling Stock
Lunar White
One of the standard colours used in railway signalling established by specification for roundels, lenses, association of American railroads (AAR) manual, namely, red, yellow, green, lunar white for roundels, lenses. Lunar white is white with a blue tinge.

Regional
Disciplines: Train Control