Factorio Forums

I found a way to Prohibit a path, if any other path are available.

I use this system to avoid some train to go to station waiting path. So now my train are not block anymore. Only train to my station go to the path of the station.

Just add a signal, force to red, if signal front of it is green
And this block signal become green again when a train come to my station. It force train to not use this way if a other way are available.

Doesn't that also cause the right train to slow down at the signal?

It depend. Most of the time, right train slow down because it break for stoping to the station, so signal turn green enough faster to not slow down trains.

mrvn wrote:Doesn't that also cause the right train to slow down at the signal?

The previous signal will always turn yellow before the stopping distance for the train reaches the red signal.

This works as long as there's not much congestion. If the other path is congested with trains a train may decide to go thru the red signal anyway.

Very cool trick.

It's going to have it's limitations, sure, but what doesn't?

Yoyobuae wrote:

mrvn wrote:Doesn't that also cause the right train to slow down at the signal?

The previous signal will always turn yellow before the stopping distance for the train reaches the red signal.

This works as long as there's not much congestion. If the other path is congested with trains a train may decide to go thru the red signal anyway.

Ahh, didn't consider that. So for the right train the second signal just has to turn green in the time between the first signal turning yellow (train reserves first tile of the block before it) and the train needing to reserve the second signal. So one has the size of the block before the first signal to switch. Certainly takes more than the one tick the signal needs to change so it should be fine.