Train Movement Sequences
In Fig 3, train 7752 has started and is now occupying track circuit 105 as well as 107. Signal C23 has returned to danger. Remember that the diagram seen by the signalman is not to scale so that track circuit 105 is a lot shorter than 107. This will distort the view of the passage of the train. An experienced signalman gets used to it.
Fig 3 - Route occupation display
Note that the track circuit for crossover 76 has been split into two parts, even though the points at the two ends must be set and locked together for the crossover move. The splitting of the track circuit allows trains on the up and down lines to pass freely.