Factorio Forums

Hi,

I have been looking for an answer for this, but not yet clarified.

I need to load and unload trains, the thing is that as you all know , we need to balance all the wagons so that the whole train won't be waiting for a single wagon. so we need to balance all the wagons.

what is the best (ups friendly) way to achieve this?

I am trying to build a big base, and need ways to optimize for ups and your help is appreciated.

I am not sure about UPS. One thing I do know is that balancers will draw evenly upon all the cargo wagons. Bots, not quite so much.

Bots delivering to, or picking up from, nearer chests will finish any one trip faster. Thus, it can be sent on a repeat trip that much sooner, which results in that nearer chest being filled (or emptied) faster. There are ways to try to circumvent this (more bots; use of Active Providers instead of Passive Providers, which causes its own issues; careful positioning of the supply and destination chests) but all they can do is slow this down, eventually you will have the first cargo wagon empty long before the final one to empty gets emptied.

OF course, using bots reduces the number of inserters needed to move the item from train (to chest to chest) to destination machine. Wagon->Chest->Belt->destination machine, as opposed to Wagon->Provider Chest...Requestor Chest->destination machine.

astroshak wrote: ↑

Sat Apr 03, 2021 9:23 pm

I am not sure about UPS. One thing I do know is that balancers will draw evenly upon all the cargo wagons. Bots, not quite so much.

Bots delivering to, or picking up from, nearer chests will finish any one trip faster. Thus, it can be sent on a repeat trip that much sooner, which results in that nearer chest being filled (or emptied) faster. There are ways to try to circumvent this (more bots; use of Active Providers instead of Passive Providers, which causes its own issues; careful positioning of the supply and destination chests) but all they can do is slow this down, eventually you will have the first cargo wagon empty long before the final one to empty gets emptied.

OF course, using bots reduces the number of inserters needed to move the item from train (to chest to chest) to destination machine. Wagon->Chest->Belt->destination machine, as opposed to Wagon->Provider Chest...Requestor Chest->destination machine.

Thanks for the message.

as you have said , using bots uses less entities... like inserters and balancers ...
my requirement is 21.5k iron per minute for a tile....
it requires about 8x8 balancer, if I intend to do it with bots , it takes about 100 -150 bots I guess ....
so , which one do you think is better for UPS ?

varundevan wrote: ↑

Sat Apr 03, 2021 3:32 pm

as you all know , we need to balance all the wagons so that the whole train won't be waiting for a single wagon.

Only if you use the "full cargo inventory" wait condition. Try setting "time passed" instead if you don't want to wait.

DaveMcW wrote: ↑

Sun Apr 04, 2021 12:19 pm

varundevan wrote: ↑

Sat Apr 03, 2021 3:32 pm

as you all know , we need to balance all the wagons so that the whole train won't be waiting for a single wagon.

Only if you use the "full cargo inventory" wait condition. Try setting "time passed" instead if you don't want to wait.

Thanks for the message.
yes , that can be done ,but
that might result in in efficient train schedules, the train will be running continuously, and that takes UPS

If the overall time to fill all a trains wagons is shorter by using bots, then it doesn't matter if they are filled in a balanced way; time-wise anyway.

Of course, if you are at mega-base stage then inserters will fill a wagon pretty damn quick.

I had same problem for my base so I shall list what I tried. maybe you can take these as suggestions depending on your play style. I use belts for factories but bots unload/load to/from blue belts (I use bots for balancers, high amount requester chests solve balancing problems generally).

most of my stations require lets say 17 chests, 9 chests, 14 chests to load/unload as target or source. not even a balancer exists for these numbers for a 4 wagon train. in past I used big balancers (24x24) but UPS was bad. my 2k vanilla base was having 40UPS (my computer can run UPS optimized bigger bases actually so it was my mess up). there were many balancers, big ones, all around the base. I did not try to solve the problem with balancers again.

I also have the "some wagons are not empty" situation. simple wait condition "cargo empty OR 30sec" worked fine in some cases and I do not think it is inefficient. most of the time you have to be careful about that duration, 30 is not a good number sometimes, sometimes it is fine, sometimes changing.
one minor thing I can add about it. one wagon is not empty is not a big problem if you are unloading. lets say you are using 2 sides. and 4 wagon train becomes 48 (logistic) chest for you. at very dire circumstances you shall have 6 chests full which prevents train moving, and depending on your case it might be enough. but it has a benefit. next train shall unload within a few seconds because all chests are empty (also other side of the stuck wagon). if other side is also full then it is even better, it becomes 12 chest of buffer and it is generally more than enough. I believe this is kind of self balancing. of course chest positioning matters a lot and it creates this situation anyway.

another stupid idea I tried was balancing wagons to side by side. 4 wagon train would balance 1>2, 4>3 wagons. in unloading most of the time the first or last wagon was not empty. I put inserters from chest to chest, the 2 chests between two wagons next to each other (1 inserter), can become 2 inserter if using other side. again it is not suitable or effective but it is a way to get rid of final bits of items to make train move. you need to know which wagon is stuck and set direction of inserter. sometimes it is just fine.

another trick I tried was to unload to chests but then bots would them to another chest to fill another dummy wagon, or two. for example I need 10 outputs. I would run into problems with using more from a wagon. I would unload like 2 belt per wagon, and then fill another dummy wagon and unload 2 belt from there, basically 8 to 10 balancer with a n imperfect ratio. it works in some numbers. it can cause further issues about UPS since you shall have more inserters now.

another attempt was to add buffer on count instead of "empty/full". lets say train moves when %80 is full, or %20, "item count > X" or "item count < X" instead of full cargo or empty cargo (especially on oil wagons because of fractions), that X would be mostly 1k (half wagon ore) for me. I am not sure if it is UPS bad because now train continuously checks a count in train.

finally I decided to use loaders/unloaders and infinite power bot mods though, I did not bother to be vanilla only. if you are fine using them then you have many options or even solve the problem with mods easily. merging chests are also an option, there is a mod for it. kind of cheating but I did not want to bother about this anymore.

now my stations are like 4 wagon train unloading to 48 passive logistic chests and bots move items to 20-30 requester chests which unload to 20-30 bluebelts with unloaders, same with loaders. with regular bots and roboports the numbers shall be lower but also depends on your base, or design. it i megabase anyway so numbers shall always be high.

cheers

You can balance both loading and unloading by using active providers on the unloaders, filtered storage chests as the input to your machines, and then normal providers/requesters for your machine output and train loading.

I use the following with great success:

Train -> active provider -> bot -> requester -> belt
(and the other way around)

The bots only need to fly a short distance. This way, the bots "only" take care of the balancing.
It would be more UPS friendly to avoid belts completely but I don't like the mess on the screen. I can't see my cursor if 10000 bots are on the screen.

The loading/unloading with bots is uneven because bots travel to the closest location. There are several option to avoid this. I like these two:

1. More train stations. The problem behind the uneven unloading is the reduced throuput when only the last wagon is being unloaded. More stations = more throuput.
2. Use: Train, inserter, chest, inserter, provider chest. Use logic to balance the second inserters. You can find smart contraptions on the forum, but a "stuff<500" connected to the furthest chest(s) is also fine.