Unbalancers
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Unbalancer
Overview
The Idea behind unbalancers is, that you want to keep the traffic on 1 lane while the second lane is as empty as possible. The principle is called SML.
Simple Unbalancer
To move trains onto one single lane, a track between them is made. To prevent trains switching tracks while a train is close to the switch, priority is added. To force the switching, a penalty is added to the track that has to be empty.
Unbalancer with Bypass
If a switching train is jammed and is blocking the upper track, a bypass is made. The bypass ensures the continuous flows of trains on the upper track. The bypass also needs a penalty station, else trains will use the bypass and not switch to the lower track.