Glossary of Terms


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JIS
Japanese Industrial Standards


Disciplines:
Abbreviation for 'Japanese Industrial Standards'.
Overseas
Disciplines: Rolling Stock
Joggled Stock Rail
A stockrail joggled such that a thick tipped point switch fits into the set in the stockrail, so that the running face of the switch lines up with the running face of the stockrail. With facing points the opposite point switch is frequently housed.

Preferred
Disciplines: Infrastructure
Joint (rail)
The location where two rails or trackwork components are connected.

Preferred
Disciplines: Infrastructure
Joint Hopping
Where fast-moving short vehicles pass from one track circuit to the next, the difference between the pick-up and drop-away times can cause the vehicle to momentarily be undetected.
Also called Block Skip.

Regional
Disciplines: Train Control, Electrical
Joint Occupancy
Simultaneous occupancy of track within defined limits.

Preferred
Disciplines: ALL Disciplines
Jointless Track Circuit (JTC)
A track circuit which does not require insulated rail joints at its extremities. The extremities are defined by the use of electrically tuned zones.

Regional
Disciplines: Train Control, Electrical
JTC
Jointless Track Circuit


Disciplines:
Abbreviated term for 'jointless track circuit'.
Alternative
Disciplines: Train Control, Electrical
Jumbo
Jumbo refers to container height and specifically to those containers which are over 2.7m or 9ft in height.

Legacy
Disciplines: Rolling Stock
Jumper
A length of conductor provided with clamps for use as a temporary electrical connection to bridge across a gap, for example, in a pipe, running rail, cable sheath, and catenary system.
And:
An interconnecting cable between vehicles in a train to provide electrical continuity.

Preferred
Disciplines: Electrical
Junction Indicator
An Indicator provided at a junction signal to inform the driver which way a junction is set, by means of a line of white lights.

Regional
Disciplines: Train Control, Operations
Refer to Route Indicator and 'position light junction indicator'.
Alternative
Disciplines: Train Control, Operations
Related Term: Route Indicator
Junction Joint
The connecting joint of rails of differing rail sections.

Preferred
Disciplines: Infrastructure
Junction Repeater Signal
A junction repeater is displayed at the signal in rear of the signal at the junction, when that signal is cleared, to inform the driver which way the junction is set. It consists of five lunar white lights inclined towards the direction the route ahead is set. Generally used to provide drivers of heavy freight trains with advance information that a route through a high speed turnout is clear.
This is different from turnout repeater.

Regional
Disciplines: Train Control, Operations
Junction Signal
A signal protecting facing points over which more than one main route is available.
In colour light signalled areas, the term junction signal also applies where there are facing points ahead of the signal and the straight-ahead route is not a main signalled route, although it might appear to a driver to be an available route.

Regional
Disciplines: Train Control
Junction Weld
A weld used to join two rails of differing sections.

Preferred
Disciplines: Infrastructure
Just Culture
An occurrence investigation environment which acknowledges human error and encourages honest reporting of errors whilst establishing clear accountability for errors.

Preferred
Disciplines: ALL Disciplines