The above image shows many of the features of the diagrams, most notably the white lines representing each track. Other features are detailed below.
Train Describer Berths
This image shows how Train Describer (TD) Berths are displayed on the diagrams. TD Berths are primarily used to display Train Reporting Numbers (headcodes). They are formatted as follows:
- A green TD, as shown above, means it is a valid headcode and probably* represents a train. These headodes are clickable and will take you to a Realtime Trains search for the train.
- A white headcode doesnt necessarily* represent a train and is most likely a reminder for the signaller, for example BLOK means the line is blocked, **** means the signalling system has detected a train but doesn't know what it is.
- A blue headcode represents 1Z99 which is a special train, usually a rescue train for another failed train, though it can be used for snowploughs, overhead line inspection or de-icing trains.
- A pink headcode represents a London Underground train, usually between Queen's Park and Harrow & Wealdstone.
- Four grey blocks, as shown above, represent an empty "last sent" TD Berth, usually seen at dead-end platforms/sidings or depots
* Due to the nature of TD berths just being 4 alpha-numeric characters, signallers can input any four letter code into them. This means that some trains may be mis-labelled, intentionally (e.g. to prevent station information boards showing platform info or to serve as a reminder) or a mistake (e.g. inputting a zero instead of an 'O' or similar), meaning the above formatting is only an estimate as to what the codes represent.
This image shows how signals are represented on the diagrams.
- The top-left signal represents one displaying a "stop" aspect with no route set from it.
- The top-right signal again shows a signal displaying "stop" however this one has a route set from it, represented by the white post. It hasn't cleared to "proceed" for a number of possible reasons including points still moving, a train has already passed or the signal has approach control.
- The lower-left signal represents a signal for which the state (stop/proceed etc) isn't known. These signals may be "automatic" or in an area where this information isn't available.
- The lower-right signal is one which is showing "proceed" (either green, yellow or double yellow), this means a route must be set as well.
This is another set of signals, now with indications used for shunting and permissive working.
- The top-left signal is a basic shunt signal showing "stop" with no route set.
- The middle-left signal is showing a "proceed" aspect with a route set. It is also possibe to have a shunt signal showing "stop" with a route set.
- The lower-left signal is a shunt signal where we have no data for it.
- The top-right signal is where a shunt signal and "main" signal (previous section) are combined. This shows one at "stop" with no route set.
- The middle-right signal shows the "main" aspect cleared.
- The lower-left shows the shunt signal or subsidiary signal cleared to allow a train into a siding or to share a platform with another tain.
More to come...
How it works
This website uses the data feeds available from Network Rail. Mainly the Train Describer (TD) feed.
The TD feed provides all the data seen on the main page including the positions of trains down to the signal-level and the state (clear/danger) of many of these signals.
For further information see the GitHub repositories for this site
This site was created and is maintained by Cameron Bird.
Hosting, front-end design and other helpful code by Mark Cockburn.
Other hosting provided by DigitalOcean.
This website uses data from Network Rail Infrastructure Limited
This data is used under the licence found at https://www.networkrail.co.uk/who-we-are/transparency-and-ethics/transparency/open-data-feeds/network-rail-infrastructure-limited-data-feeds-licence/