Difference between revisions of "Signals"

Revision as of 14:13, 3 November 2017

A Block Signal in Realistic View

The Three Different Direction Configurations of Block Signals

Purpose

Signals prevent trains from crashing into each other while driving on the same track and it is for this reason that they are an important part of any railway system - safety first guys!

A signal divides a railway line into two sections known as blocks. If a block is occupied by a train then the signal dividing these blocks won't allow any other train to enter that occupied block until this block is cleared.

Placing of signals

one left mouse button click = two way signal will be placed on a railway track
second left mouse button click on the same signal = two way signal will be transformed to one way signal
(side of the track we clicked on will determine the orientation of the one way signal)

Signals cannot be placed in tunnels, on bridges, at stations and directly on railway intersections.

Different kinds of signals:

Type	Block Signal	Information
Two way signal		Allowing trains to pass in both ways - mostly used in dead end stations with low traffic.
One way signal		Allowing trains to move only in one direction - often used on double tracks with high traffic.
Chain signal		-comming soon-

Block signals explained

Block signals allows access only on the blocks which are not occupied by other train. Block is the space of railway between two signals. You can see the block status with the arrows pointing towards the segments. Red arrow means that the block in the arrow direction is occupied.

Block signals basics

signal block on straight track

station with two track and two-way signals

On the left picture you can see our example station situation with incorrectly positioned signals. Each block is located between two signals / end of the track and colored with different color. Red is the station block, blue is the "entry" block, green is the rest of the track.
In the real functional railroad with two trains, you will almost immediately hit the deadlock issue with the train. The problem is in the two-way signals on a single track. Very soon the trains will stay at one signal against each other. To avoid this, you can introduce some kind of avoiding track with one-way signals (right picture). You can notice that the station block is now split into two tracks with two one-way singal. One "entrance" signal, one "exit" signal. The incomming train will from the green block, to blue block. Then the train enters the station and blocks the red block. Next incomming train will have red sign on the entrance signal, because of occupied red block. The diference between left and right example is, that the train have a space to leave by the yellow block. This is effective enough on the low load railroads. For examples of how to use the signals, go to the Junctions page