Train Depot Design

[ppa]

Is there anyway to make a train depot that will prefer to "suck in" the incoming traffic before letting any train out of the depot? I tried using presignals from the right-of-way train depots, but it's not optimal yet. Can anyone help?

[ppa]

Ok, never mind. Got it.

[FooBar]

Would you care to show your solution? Others might learn from that.

[ppa]

I am terribly sorry for the false claim! I thought I had it, but I didn't. I thought the following design should do what I wanted it to do, but there is one huge problem as explained under "Bad thing". I found it when I was about to make this post. So, my call for help is still valid. Please let me solve this.

depot.JPG (120.21 KiB) Viewed 2514 times

Good thing about this design
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There are three 'important' signals in the design, A, B and C. A is a one-way normal signal, while B and C are two-way signals, with B being an exit and C being a combo. As you can see in the design, if an incoming train has passed A, B is red in the reverse direction and so is C. So, no train comes out of the depot until the incoming train (Train 10 in the figure) has entered the depot. In the figure, I even tested with the incoming train 10 stopped between A and B. Although there are three trains already waiting in the depot, none comes out. As soon as I release Train 10, it'll just go right into the depot. So, that's good. Incoming trains wouldn't have to wait at all if we leave enough space between signal A and B. My purpose was to use this kind of depot attached to a main line, so that all incoming traffic to the depot will be sucked into the depot without disruption in the main line. (This doesn't work if C is pre-signal instead of a combo. I don't know why.)

Bad thing about this design (which makes it completely useless)
==========================================

Let's consider the scenario where there is a train (let's call it Train 1) in the depot that is coming out soon. There is no train in the line outside, except for a train (let's call it Train 2) that is about to reach A. As there is no train between A and B, B is all green and so is C. So, the Train 1 in the depot will come out. Now, just after it comes out but before the engine has passed C (you can see this if you make the buildings invisible), let's say the Train 2 passes A. Now, B is red in the reverse direction because Train 2 is between A and B now. Since B is red, C is red as well. Train 1 hasn't passed C, so it waits just outside the depot and just before C forever. Everything's blocked!

[zombie]

Hi.

Just skip the combo presignal in this setup. The exit signal inside the depot is a entry presignal. Therefor the presignal exit for the inbound track is enough. If a train leaves the depot an incoming trian might have to wait for a short time but after that it has priority above the trains inside the depot.

Kind regards

Zombie

[ppa]

Hi.

Just skip the combo presignal in this setup. The exit signal inside the depot is a entry presignal. Therefor the presignal exit for the inbound track is enough. If a train leaves the depot an incoming trian might have to wait for a short time but after that it has priority above the trains inside the depot.

Kind regards

Zombie

Thanks for the reply. I think I read it somewhere about a signal inside the depot but was never sure of it. Thanks for confirming it.