Tutorial 5. Adding Stops and Signals
Open the layout from Beginners Guide Part4 and save it with a new name.
It gets a bit boring having the train running round and round in circles non-stop, so lets add a station.
First, make sure that you’re not in track-laying mode, to avoid creating any accidental trackwork.
Right-click on the track and select Insert Node to insert an extra node near the exit end of the loop.
Point the mouse at the yellow mark on the other track, right-click and select “insert node” to put a matching node on the main line. Notice how the new node snaps to align with the other one.
Now right-click one of the new nodes, and select Stops and Reverse - New Stop.
The Stop dialog opens:
(If the stop dialog does not open automatically, double click the node to open the dialog)
If the arrow is not pointing in the direction of travel of the trains, press Change. Otherwise leave the options as they are for the moment and click on ok.
Repeat for the other track.
Watch the train - it will come to a sudden halt when it encounters one of the new stops. This suddenness is because there are no signals yet - the train needs a signal as reference point to slow down for a stop.
It’s very easy to add signals: you decide where to place the signals on the track and the Rail3D signalling system does all the rest…
As well as making trains aware of stops, signals have the much more important function of controlling trains to prevent two trains from entering the same track section. If you were to put a second train on the layout without adding signals, you would soon have a collision.
A signal can be added to any node. However, it’s recommended not to put a signal on the same node as a switch or a stop. For our simple layout, one possible way to divide it into sections is like this (each colour represents a section):
This arrangement allows a train to be stopped in one of the two station tracks without affecting trains passing through the other one. Breaking up the “main line” into two parts also makes life a bit easier - if we did not do this, then the first train would have to be completely off the main line and within the station loop before the second train could leave from the other track.
To achieve this arrangement, we need to place signals at the four nodes marked in the diagram. (In real life we would have to modify this arangement a little to allow for the possibility of trains over-running the loop exit signals, e.g. by fitting catch points: for the purposes of this exercise we’ll assume that speeds are too low for this to be necessary.)
First of all, add starter signals at the nodes immediately beyond the stops. Right-click on the node, and select New Signal.
A signal appears by the track at the node. Double-click on the node to open the signal dialogue.
As with the stop, make sure the arrow is pointing in the direction of travel of trains. Click on Change if it is not.
We also need to select the controlled signal option.
Note — Controlled and automatic signals
Modern signalling installations of the type modelled by Rail3D divide signals into two categories: automatic and controlled. (Semaphore signals are treated differently - we will not be using them in this tutorial.)
- An automatic signal, as the name implies, is not operated by the signaller, but simply reacts to the occupation of the track sections ahead: if the line is clear, the signal shows a proceed aspect (green, yellow, or double-yellow in the British system); if the line is occupied, it shows danger (red). Signals in Rail3D are automatic by default.
- A controlled signal normally shows danger (red). It only clears to a less restrictive aspect when the signaller sets a route for a particular train. In Rail3D there is no signaller: the signalling system detects the approaching train, determines where it is going, and sets the route from the controlled signal as soon as the line is clear.
The reason for this difference is easy to understand if you imagine what would happen if you put automatic signals at the exits from the loop tracks in our layout. Both signals would normally show green, but as soon as a train passed one of them to leave the loop, both would change to red together. If a train were approaching on the second track, the driver would see a signal changing from green to red in front of his nose, far too late to stop and avoid a potential collision. On the other hand, if you used controlled signals here, both would normally show red. When the first train approaches, the signal system sets a route for it and clears the signal for that line only, so the second train sees a red signal and is able to stop safely.
The starter signal is protecting a point where two routes converge, so it should be a controlled signal, which is normally at danger and only clears when a train asks for a route. Click on the check-box to select this mode.
Repeat for the other track.
We also need to use a controlled signal at the entrance to the loop, as an automatic signal would not be able to take account of the state of the points, and would only clear when both tracks were free. Add this controlled signal one node before the entrance to the loop.
Because this signal comes before a junction, we can replace the default signal model by one with a left-hand junction indicator. Open the signal dialogue and click on Type to open the signal selection dialogue, then browse to uk/3Aspect:
Finally place an automatic signal somewhere on the other side of the oval.
Watch the train - notice how it now slows down gracefully when approaching the stops. The starter signal will be at danger when the train comes into the station, and should clear when it is ready to leave. The starter on the other track remains at danger to protect the train from flanking movements.
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Notice too how the junction indicator warns the driver when we are being routed into the loop:
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You can download the layout from this tutorial here: tutorial5.zip (195kB)
Optional further steps
Optionally, you could add another train at this point. Since the signals are only set up for one direction of travel, be sure to place the train at the “clockwise” end of a link to make sure that it starts off the same way as the other train. Find something suitable, and drag it to a node well away from the current position of your first train (see Beginners’ Guide Part 3 for how to do this).
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The two trains should run alternately round the oval. For a change, open the point dialogue for the facing points at the loop entrance, remove the * from Alternate and put it in Free Route instead. This allows the trains to take whichever track is not occupied.
It looks a bit strange having steam trains controlled by modern colour-light signals; you could easily replace them with old-style mechanical signals — see Semaphore Signals for advice on how to do this.