Train time intervals not staying at a fixed amount

[lukey77]

This has been driving me crazy trying to fix this. Have my trains on a certain route set for an interval of 40 mins. Trains start at my main terminus, run to the end and back, then into a siding and back into the platforms to run again. After a few hours they are now 40 mins 10 seconds apart. After a day its about a minute. I have looked at my path signals, stop times etc and nothing should be effecting any of my trains. Is this a glitch or am I missing something?

[MirkoC407]

Have noted that either. About 5 minutes after a weekend with night services, i.e. out of depot Friday morning, back in Sunday evening. And no idea where it comes from. Was like that already before that infamous 3 minute delay patch.

[Weird and Wry]

v1.4 and earlier have no timing guarantees and trains make no effort to match any fixed timing, they only check a timer in the interval stop(s), which can and will add a random second from time to time due to rounding errors. v1.5 will have fixed timetables with fixed arrival and departure times.

[MirkoC407]

Thanks for clarification. With usually about 10 minutes, never less than 6 (a normal time to get a multiple unit based train ready to leave in the opposite direction) I was wondering where that comes from. I know there is no guaranteed times in 1.4 and lower, but was surprised when it managed not even to leave on a given time of X after a previous train, which for sure was possible considering time buffer at terminus stations.

[patrickov]

Originally posted by MirkoC407:

I know there is no guaranteed times in 1.4 and lower, but was surprised when it managed not even to leave on a given time of X after a previous train...

Consider all limits we give to a line as the minimum rather than fixed. In most cases this is explicitly written on the UI (e.g. minimum stop time)

Meanwhile, when you would want a train to go to run a line or, go to a depot, is fixed. But that time is when the train starts to do so. regardless of where it actually is.

[MirkoC407]

Originally posted by patrickov:

Consider all limits we give to a line as the minimum rather than fixed. In most cases this is explicitly written on the UI (e.g. minimum stop time)regardless of where it actually is.

For interval it is not designated minium. And that was what I wrote about. Especially with the trains being there a minimum of 6 to 10 minutes sitting each terminus, it was not clear why it could not leave spot on during the time of a weekend. There was never a reason to go later, except obviously for drifting internal calculations.

[patrickov]

Originally posted by MirkoC407:

For interval it is not designated minimum.

Effectively it is, because trains would always wait up to the interval you designated. They could only go later rather than earlier than it.

[MirkoC407]

Yeah, now we start counting lingual peanuts. Sure it won't go earlier. But with a train sitting (much) longer than its time for intermediate stops, like 60 seconds stopping time, waiting 10 minutes at the terminus on a line with 20 minutes train interval, there is no obvious reason for the player why it should go later. It is the easiest thing to actually depart bang on time 20:00 minutes after the previous train reliably if I consider front end game settings only.
So as Carlos explained, the only reason making sense is internal calculation and its rounding deviations. Which is fine for a calculated system. And of course, once you are late, you won't get back because the current system will then try to depart exactly 20 minutes after the already delayed departure and from Friday morning to Sunday evening those calculating deviations adds up...