Connections

Connections are links between two or more trains and are inserted when the vehicle is creating a condition between the arrival(s) and departure(s) between different trains. They are necessary requirement for the rostering. They are also essential to see capacity consumption by turnarounds in terminal stations. Connections can be created in the track occupation diagram by drawing a rectangle with the mouse encompassing the trains to be connected. It is also possible to use the context menu function with a right-click on the first train. It is a requirement that the trains to be connected are placed on the same track.

Connections are created for each train and operating day individually. If there are many variants and operating days in use, connections could be different for each calendar date. It is good practice to create connection only after the timetable has been checked for conflicts.

If connected trains need to be modified there are four different possibilities, depending on the specific modifications:

1. The connection is removed before changes are made to the timetable. This is the recommended method and ensures full control for the planner!
2. The connection is not removed, but unaffected by the changes: Nothing happens!
3. The connection is not removed and affected - it changes the status to invalid: The connection can be restored, when the conditions for its validity return (for example by modifying the second train, too). If no further modifcations are made, the connection will remain invalid. It is possible to create completely new connections.
4. The connection is not removed and the modification is blocked: Nothing happens!

Connection validity

A connection can be invalid for a couple of reasons:

• train order
• entry type pass
• different tracks
• missing track information
• train deleted or missing

An invalid connection can return to an valid status is the reason for invalidity is removed, for example if the train order is restored. An invalid connection is not visualised in the track occupation diagram, therefore the connection table should be checked.

Balanced Connection

The connection is checked for balanced incoming and outgoing trainset parts. If the connection is not balanced and either more outgoing or more incoming trainset parts are part of the connection, or the connection is of entirely different trainset parts, or one of the trainsets does not have trainset parts, a coloured triangel will appear to highlight the need for user intervention:

1. Violet: Trainset information is missing for one or more trains.
2. Rose: Trainset parts information is missing for one or more trains.
3. Orange: Trainset parts are not the same.
4. Yellow: Number of Trainsets parts is not balanced between incoming and outgoing trains.

Connection table

Under the Timetable tab the connection view displays the list of all connections (valid and invalid). It allows the user to delete connections, especially the invalid ones that are not needed any more. It also allows to modify certain characteristics of the connection, such as Minimum Turnaround Time or Operating Period.

Conflict checker for connections

The conflict checker "Turnback time" checks the planned turnaround time against the Minimum Turnaround Time (MTT). The MTT can be set manually in the connection table or in the trainset information in the Project. The check "Turnaround connections" checks for missing connections or problems with existing connections (in other words if connections are valid and balanced).

Operating Days of a connection

The normal operating days of a connections are dictated by the operating days of the trains forming the connection. The Default operating calendar for a connection is the intersection of all operating days of all trains connected. A special case is the connection spanning more than one operating day (see dedicated chapter below).

Additionally, the user is able to define a subset of the operating days of the connection, for example a single day of validity. This is relevant, when the trains connected have different connections on different days of the week.

Connections spanning multiple days

Connections between trains on different days can be present if different forms. The connectioon in itself doesn't change, but the user might want to handle them differently than simple turnaround connections.

Connections over midnight

Connections over midnight can be between two trains of the same operating day (e.g. a train arriving at 23:55:00 and a train departing at 24:15:00) or between trains of different operating days (e.g. a train arriving at 23:55:00 and a train departing at 00:15:00 at the following operating day) - see below.

Connections between trains on different operating days

Connections trains of different operating days are managed in the same way as connections between trains of the same operating day. They only have a day shift of one day. If the activity period is restricted (Operating calendar is NOT Default, but Custom Calendar), the first train is relevant for defining in which calendar day the connection is active.

These kinds of connections are possible to generate from the track occupation diagram, either by drawing the rectangle or by the use of the contect menu "Connect to the next train", if both trains are visualised in the diagram. If the next train is not visible the context menu offers a second option "Find next trains" which will search for the next train on the same OCP track in the span of 72 hours to connect to.

Connections between trains on different operating days with connection durations longer than 72 hours

If for operational reasons trains are parked for longer periods on station tracks, and therefore consume capacity relevant for timetable planning, a connection with a duration longer than 72 hours can be created. This is not possible from the track occupation diagram, but in the connections table. There the OCP and OCP track can be specified and two train codes are inserted. The connection is formed for one Activity Day, based on a single operating day of the first and second train, both individually selected by the user. It is not possible to generate connections representing split and join operations with this function. (Will be available from v1.19 onwards)

Automatic connection creation

In the track occupation diagram the Automatic Turnaround function can be used to create many connections together. Please note that the connections are formed only for the trains visibile in the diagram and for the intersection of the Operating Days of both trains.