Glossary of Terms


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Narrow Gauge
The track gauge of 1067mm (3' 6').

Preferred
Disciplines: ALL Disciplines, Infrastructure
National Transport Commission (NTC)
Body established under a Commonwealth Act
and an inter-governmental agreement with a charter to develop, monitor and maintain uniform
or nationally consistent regulatory and operational reforms relating to road transport, rail
transport, and inter-modal transport. This body is funded jointly by the Australian
Government, states and territories.

Preferred
Disciplines: ALL Disciplines
NCO
Network Control Officer


Disciplines:
Neck
A small line of track in a yard used for the shunting of a locomotive.

Regional
Disciplines: Operations
Nested Containers
Nested containers refers to the transport of multiple empty containers to a location using a single slot on a particular wagon.

Regional
Disciplines: Rolling Stock, Operations
Net Tonne Kilometre
Net tonne kilometres is a measure of the payload of wagons (the net tonnes) multiplied by the distance travelled.

Preferred
Disciplines: ALL Disciplines
Net Train Weight
The weight of hauled vehicles in a train consist.

Preferred
Disciplines: ALL Disciplines
Network
A combination of track and other infrastructure controlled by an Rail Infrastructure Manager.

Preferred
Disciplines: ALL Disciplines
Refer to Railway Network.
Alternative
Disciplines: ALL Disciplines
Related Term: Railway Network
Network Access Level Crossing
Generally permanent level crossings provided at authorised locations for Network maintenance.

Preferred
Disciplines: ALL Disciplines
Network Control
The function responsible for managing train paths and issuing occupancy authorities.

Preferred
Disciplines: ALL Disciplines
Network Control Officer (NCO)
A Competent Worker who authorises, and may issue, Occupancy Authorities, and who manages rail traffic paths to ensure safe and efficient transit of rail traffic in the Network.
The Competent Worker may be known a Train Controller, Network Controller or Signaller.

Preferred
Disciplines: ALL Disciplines
Network Control Officer Directions
Any instructions issued by Network Control relating to the management, maintenance movement and safe operation of all traffic within train control territory.

Preferred
Disciplines: ALL Disciplines
Network Notice
A notice issued by an Rail Infrastructure Manager which contains safeworking information for workers.

Preferred
Disciplines: ALL Disciplines
Network Registered
Rolling stock that the Rail Infrastructure Manager can consider for train or route acceptance.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Network Registration
The process used by a Rail Infrastructure Manager to permit initiation of the train acceptance process.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Neutral Relay
A relay which operates in response to a pre-determined change of the current in the controlling circuit, irrespective of the direction of the current.

Preferred
Disciplines: Electrical
Neutral Section
An arrangement of insulators and earthed equipment introduced into the overhead line equipment and designed to ensure that two adjacent electrical sections are kept separated even during the passage of the pantographs of electric trains.

Preferred
Disciplines: Electrical, Infrastructure
Neutral Temperature
The rail temperature at which the track has no longitudinal thermal stresses.

Preferred
Disciplines: Infrastructure
Non Bulk Freight
General freight, comprising containerised freight, steel, motor vehicles, paper products and other general merchandise.

Regional
Disciplines: Operations
Non Conformal Contact
Contact between the wheel throat and rail gauge corner giving a gap of more than 0.4mm between their undeformed shapes.

Preferred
Disciplines: Rolling Stock, Infrastructure
Non Detectable
Rolling stock that does not activate track circuits.

Preferred
Disciplines: Rolling Stock, Electrical
Non Electrified Route
Not equipped to supply power to electric trains.

Preferred
Disciplines: ALL Disciplines
Non Field Lubricated Bearings
Bearings that do not require any lubricant to be added during the service period.

Preferred
Disciplines: Rolling Stock
Non-automatic Signal
A signal that is not controlled by track circuits.

Preferred
Disciplines: Train Control
Non-controlled Location
A location where the rail traffic crew carries out the signalling and Safeworking operations.

Preferred
Disciplines: ALL Disciplines, Operations
Non-interlocked Points (on Signalled Running Lines)
Points which are not interlocked with the signalling and which must be securely locked by spike, point clips or clamps, and XL locks.

Preferred
Disciplines: Operations, Train Control
Non-storage Operation (anti Pre-selection)
A term used when pre-selection (storage) of a route is not provided and where the control to move points can only be set up if the points are free or available at the moment the control is applied.

Regional
Disciplines: Train Control
Non-vital
Signalling equipment and circuits are considered non vital where failure to function correctly would not cause an unsafe outcome of the signalling system. Non-vital equipment and circuits do not affect the safe operation of the signalling system.

Regional
Disciplines: Train Control, Electrical
Non-vital Blocking
Non-vital blocking is blocking which is incorporated in an operator Interface or train control system to inhibit specific controls to call routes and points from being sent out to an interlocking.

Regional
Disciplines: Train Control
Normal Contact
A term used to designate a current carrying contact when the operating mechanism is in the normal position.

Regional
Disciplines: Train Control, Electrical
Normal Direction
On a line for which the signalling is provided for one direction only, Normal applies to the signalled direction.

Preferred
Disciplines: Train Control, Operations
Normal Operation With Train Protection And Control (TPC)
This is when all TPC systems are operating and trains are running up to permissible speeds.
(Train and infrastructure systems are within maintenance tolerances.)

Preferred
Disciplines: ALL Disciplines
Normal Position
The position in which signal and other devices are assumed to normally lie, according to rule, convention or otherwise, i.e., stop aspect displayed, points set for main track, devices energised or de-energised, etc. The normal position generally refers to the position where the protection is applied e.g. signals at stop, releases locked and not available.

Preferred
Disciplines: Train Control, Operations
Normal Speed
A speed that does not exceed the speed limit currently in effect for the location and type of rail traffic.

Preferred
Disciplines: Operations, Rolling Stock
Normalise
Cancellation of a set route and release of the interlocking including approach locking, but not including route locking being maintained by a train within the route.

Regional
Disciplines: Train Control
Nose
The machined or point end of a crossing near the point of intersection.

Preferred
Disciplines: Infrastructure
Nose Rail
The rail used to manufacture the nose of a crossing. It forms a V with the scarf rail.

Preferred
Disciplines: Infrastructure
Refer to 'female half of vee'.
Alternative
Disciplines: Infrastructure
Nose To Nose Interlocking
Directional interlocking which may be cancelled, under certain conditions, to permit entry to an occupied track.

Preferred
Disciplines: Electrical
NTC
National Transport Commission


Disciplines:
Abbreviation for 'National Transport Commission'.
Alternative
Disciplines: ALL Disciplines
Null Count Test
This is a check against the circuit book analysis sheets to verify that there are no wires terminated on spare contacts of relays and other operating mechanisms, nor on spare fuses, links, terminals, and all other spare termination points.

Regional
Disciplines: Electrical
Number Light
Backlit vehicle number.

Preferred
Disciplines: Rolling Stock