Train buffer/Wait station conditions

[Nonotorious]

So despite playing this game for over 2700 hrs i have never built a train buffer so i figured i would try it out on my current map. However i am having a problem trying to set up the wait conditions for the trains properly.
right now it looks like this:
https://steamcommunity.com/sharedfiles/filedetails/?id=2544258480

The dropoff station boxes are connected to the station which toggles on and off depending on demand, the limit is set to 1 so trains are forced to stay at the wait station before heading to unload and send to train box is also ticked which should be sending a signal to the train but i cant seem to figure out what.
The trains are set-up to move if there is no activity, empty or at 30s if there is too much being used from 1 of the cargo wagons and new train will come in.
The problem is i can't figure out the circuit network wait condition for the wait station, i put wait 30 in there just so they wouldn't just continue to drive around looping until the fuel runs out. If there is a signal being sent to the trains from the dropoff station i should be able to use it to make them stop there without having to mess around too much with the circuit network.

[AlexMBrennan]

Remove the 30s wait condition.

If there is a signal being sent to the trains from the dropoff station i should be able to use it to make them stop there without having to mess around too much with the circuit network.

I would not recommend doing this with circuits; it is theoretically possible but very difficult - you need to keep track of open requests for resources, and trains currently en route to the destination to dispatch one train for each open request.

[Nonotorious]

That is a placeholder so they don't continually loop when the dropoff stations are turned off.

[AlexMBrennan]

OK, there might be a small misunderstanding here - do you disable the stations or set train limits? If you disable the stations then you need to not do that and only use train limits.

If you set the train limit to 0 if no resources are required, and to 1 if some resources are required then the trains will wait at the stacker if no unloading station is available even if you do not have a wait condition. That is what you want.

[Nonotorious]

Yes i was disabling them when the ore was filling past a certain point and it runs pretty smoothly its just the wait condition that was wasting fuel.
How does the train limit option work it doesn't have any numbers or options it just outputs a signal? Now they are just sitting there at the wait station while the dropoff empties.
Obviously i can wire it all up but if the options are there they should be easy to use but i don't understand em.

Here's what they look like atm:
https://steamcommunity.com/sharedfiles/filedetails/?id=2544432761
https://steamcommunity.com/sharedfiles/filedetails/?id=2544432887

[knighttemplar1960]

You can remove the train stations in the copper wait station stacker and remove that stop from your train consist. If this is the ONLY area where you have stations named like this you can leave the train limit blank on each unloading station and all of the copper ore trains that have this station as their stop will wait in the stacker for an unloading station to open up. All you have to do is make sure that you have a number of rail sections in the stacker to allow all the trains with this stop to wait without blocking the incoming rail. So if you have 9 ore trains you need the 3 stations and 6 parallel lanes for the trains to wait in.

If you have 2 smelting locations like this and 18 trains then you would want to set a train limit of 3 on each of the stations. You can also do that with more than 18 trains and only 9 will be at each unloading area. The other trains will wait at the loading areas until a spot opens in one of your smelting areas so you would have to make sure that there is a stacker big enough to hold the extra trains at the loading areas to make sure that you don't get a bottleneck. You will want to set train limits on those station also to make sure that your trains are evenly distributed.

To make sure that your unloading is evenly distributed at the destination you can unload from a rail car into 4 chests that then unload onto a belt system something like this.
https://steamcommunity.com/sharedfiles/filedetails/?id=2525797981
this will give you a fully compressed belt from each rail car and you merge the belts into a lane balancer to solve the uneven unloading problem. That will allow you to set your rail stops to load full cargo and unload full cargo and each train will only have 2 stops so it will always be waiting at one or the other when it isn't travelling. No looping back around and around.