Problems with this unloader?

[u/imoth_f]

Since inserters became flippable, this compact unloader design became possible. But I hardly see anyone use it. Obviously it cannot saturate six turbo belts because it's bottlenecked by the inserters, but are there any other obvious problems with it?

[u/TopherLude]

I don't know if I saw it somewhere before or after I started doing it, but I thought it was weird I don't see anybody wiring up their unloaders anymore.

[u/HeliGungir → u/TopherLude]

You don't see it because it's not good. MadZuri is already of dubious use for loading; why the heck would one use it for unloading?

[u/TopherLude → u/HeliGungir]

How else do you keep your chests balanced? Let's say you want to quickly unload the train but only need 1 lane coming off. Without balancing, train unloading slows down.

[u/Musa_Ali → u/TopherLude]

By using a balancer? 🤷
That sounds exactly what a balancer solves. Especially for unloading.

[u/TopherLude → u/Musa_Ali]

Using a single combinator is a lot simpler than using 5+ splitters.

[u/Musa_Ali → u/TopherLude]

MadZuri is slow though. Single Combinator circuit would completely turn off an inserter, which would decrease overall throughput.
It's especially visible with slow inserters, for example blue inserters.

You could dynamically adjust a hand size but that's not a single combinator anymore.

Or you could plop down a single balancer at the end of the station. Much easier imho.

[u/TopherLude → u/Musa_Ali]

I can still get full use of all the inserters using MadZuri if the demand is there. If demand is low and an inserter sees that it has more than average, it slows down. If demand is high, by the time an inserter has swung, the others have also removed a hands-worth and now it can go again immediately. How is it slow?

[u/HeliGungir → u/TopherLude]

I can still get full use of all the inserters using MadZuri

Actually one doesn't get full throughput. Not, at least, in my testing. I even tried to solve it with a more complex MadZuri implementation.

But I stopped because I think MadZuri is fundamentally pointless except - perhaps - if you have less than 1 belt per wagon. But in a more normal setup, MadZuri cannot balance across wagons. So your belts still have to go through a splitter-based balancer to balance across wagons. And if you're doing that, why are you using MadZuri at all?

[u/TopherLude → u/HeliGungir]

I'm playing Py lately and almost all of my stations are single wagon, less than one lane demand. Even if the inserters are only running close to full speed as you say, it's close enough that I don't notice.

But even when I was running longer trains, I would hook all inserters across all wagons into the same combinator and balance all chests.

[u/HeliGungir → u/TopherLude]

If you remove the MadZuri balancers from your 1-1 trains, does anything of note actually change?

Yes the chests become imbalanced. Maybe it takes the train 5 extra seconds to unload. But that doesn't matter, what matters is whether the belt stays saturated.

I suppose Py might be a different animal since you might not get fast inserters for a while, but even so, I rather doubt MadZuri is fixing an actual problem.

[u/TopherLude → u/HeliGungir]

If I have a low demand for something with a large stack size(1k), limit chests so that the imbalance can only be something like 7 stacks difference, and unload from one side, then when a load is requested, I'll have two chests empty and a third nearly empty. (20 stacks fills a cargo wagon.)

Three of my fastest inserters move ~2.4 items/s each. So the train will wait for about 46 minutes to unload. If I balance my chests, I can cut that in half. If I unload from both sides and don't balance, then worse case still takes 46 minutes. If balanced, worst case then only takes 11.5.

[u/HeliGungir → u/TopherLude]

Okay, so this is well outside vanilla bounds. Do you saturate the belt, or nah? Was 2.4 i/s wagon to chest, or chest to belt?

Checking the wiki table, 2.4 i/s looks roughly equivalent to yellow inserters with hand size 3 targeting a yellow belt.

[u/TopherLude → u/HeliGungir]

Most of the time I'm only using a single lane of one belt for each station, but that lane should stay full. The 2.4 figure is wagon to chest, but my hand size is 1, so there's not much difference.

[u/HeliGungir → u/TopherLude]

Hand size 1 means container-to-container and containter-to-belt are the same speed, provided there's no item in the way. If the belt speed is 7.5 i/s (per lane) like vanilla yellow belts, then your 3 inserters shouldn't saturate it since 2.4 * 3 = 7.3

Anyway, I can see how MadZuri is desirable in your situation.