Just use this https://mods.factorio.com/mod/railloader (I really think this one should be in Vanilla, ore's are always dumped in wagons from above and dumped out of from below it at the processing plant)
Even faster in combination with https://mods.factorio.com/mod/deadlock- ... es-loaders.

Alt+R turns your personal Roboport function on and off.

Thanks. Did search for 'station, contents and read'. Forgot that people will use synonyms instead of the terms actually used ingame. Tried the 'inventory sensor' mod and it's too slow... An inserter wil already insert fuel in the train before the 'inventory sensor' senses the contents of the locomot...

If you place a fuel chest next to the station and insert the trains from that chest you can read its content for your signal. How is this a solution??? This mod is a solution: https://mods.factorio.com/mod/Inventory%20Sensor Tried the mod and it's too slow... An inserter wil already insert fuel in ...

TL;DR Title says it almost all. The checkbox to include the locomotive should be separate. Why: I dislike the fact that when I delete a train I get 300 of the fuel in my inventory. I want to be able to use an inserter to only fill the locomotive with a limited amount of fuel. As you use a more 'expe...