3 ms·
Not necessarily at the exit. Normal signal: train stops if there's a train in the section ahead (or it's reserved for another train on a conflicting path), oth
by red_admiral 3y ago
Not necessarily at the exit.
Normal signal: train stops if there's a train in the section ahead (or it's reserved for another train on a conflicting path), otherwise train goes.
Chain signal: train stops here until it can get a mutex on a path past another non-chain signal.
So if you have rail sections (small letters) and signals (capitals) a - A - b - B - c - C - d in a row on a plain line and A/B are chain signals and C is regular, then trains from the left will stop at A until the train can grab all sections b, c, d in one go.
That's why chain signals at the entrance to a junction are good (prevents a train stopping on the junction) but you want regular ones at the exit, at least if some plain line follows.
- pmoriarty 3y ago"Chain in, rail out" is the standard advice. However, if you search around r/Factorio you'll see there's debate about whether that's the best advice for beginners. Chain both in and out is supposedly the foolproof method, and apart from stations, rail signals are just an optimization. Though I've played a lot of Factorio, I've never really felt the need to dive deeply in to signals, and I'm happy to just use the foolproof method and leave more optimized solutions for those who need them.
- mcv 3y agoI prefer to see it as regular signals designate the next segment as a segment where trains are allowed to wait. If you don't want trains to stop in that segment, don't put a regular signal in front of it. And of course you don't want trains stopping on intersections, because they'll block everybody, so you always put chain signals in front of intersections.
- kzrdude 3y agoThe train needs to reserve the whole next contiguous sequence of chain signals to be able to go, so the foolproof method makes it sound like each train reserves the whole path from one station to another. It makes sense, but I like to do the optimizations, then, and allowing trains to stop in longer stretches where they can.