Unusual Train Pathing

[Zaka]

I hope I can explain this clearly...

I have build a factory that has a Ore Unloading bays on the North side.
There are 2 sets of waiting bays for the Unloading Stations, one to the East and one to the West.
Ore trains are only using the Western waiting bays although they have to drive past the Eastern bays to get there.

Map

The Waiting bays have a "Selector" that turns all of the signals red and continually polls the bays until a train is present.
When the selector finds an occupied bay it will turn the signal green and allow the train to proceed.
This balances the wait time of trains that are waiting for an open Unloading Bay.

Train Using Western Waiting Bay

http://i.imgur.com/894zd5x.gifv

Can some one explain why the trains go all the way around the top when the Eastern bays are unoccupied and available?
NOTE: Trains are RHD.

Thanks,
Zaka

ps Game is Vanilla 14.12
Game Save: http://www.filedropper.com/2016072946

[ssilk]

Moved fromGeneral to Gameplay Help

[kingarthur]

i dont see any super simple reason for why they are going all the way around. have you checked the signals on the east side. if they are all red the trains might be pathing to the west side because those signals keep turning green.

maybe post a copy of your save so we can take a closer look

[Zaka]

Thanks for the reply.

ALL of the signals on ALL of the waiting bays are red until a train arrives in the waiting bay.
Once the train enters the bay, the signal will turn green (if no other bays are occupied).

Link to save is at the bottom of the first post.

- Zaka

[Linosaurus]

If you completely block off the left ones by removing a piece of rail from each entrance, do the trains go to the right? This is just to rule out that some minor error makes them inaccessible.

[Zaka]

Yes. If i remove the "link sections" between the Western bays and the main line, the trains will use the Eastern bays.

- Zaka

[Zaka]

Please Disregard.

My error. The Combinator contraption that I built does not effect train pathing the way that I expected.

Apparently, when all paths are red, the train will take the last possible option.

- Zaka

[nuhll]

Could you PLEASE share your train setup? Combinator, waiting lines? PLEASE

[Deadly-Bagel]

As far as I know, if a train cannot reach its destination it first picks out the closest spot it can get to the station. This is not affected by distance, it measures it in signals. Once it has that, it calculates the closest path to that red signal (again not affected by distance).

There are some cases where if the path is too long it will prefer a shorter route, even if the path is available the long way, but you shouldn't have that problem in this setup.