Factorio Forums

I have read the wiki and even watch the 1 hour tutorial to get at least the gist of understanding of circuit network as a whole. not sure because the game is too engineering for me or because I'm just overwhelm with the fact that there are mathematical formulas needed to use this tech to its full potential , but I still honestly dont know how to use this for practical use besides for electricity, oil, and train.

does circuit network can actually combines item? can it also process it to another items, lets say copper plate to copper cable? without the automation machine? because according to the videos I've watched he talked about input and output, and in example say copper plate, multiply by 2, set the output to copper cable, and then the whole network will find any signal with available signal and gives the output according to the setup. now, what i dont understand is this output thingy. what does it actually do? does it produce an actual output? or just gives signal, some kind of reminder, or just showing you the thing the same thing when you press ALT? is it really crucial for me to know how many items I currently have with this circuit network? or is there more to it than that?

because the very very basic setup of circuit network i saw is that it will give you the same information that you get from pressing ALT, except it tells you the numbers of items you currently have also.

for practical uses, I think the its useful for electricity because in the tutorial it tells me that I can switch from solar panel during the day and switch to steam machine during the night, means I can save lots of coal instead of relying on it 24/7.

some people on steam forum told me circuit network is optional and I can launch the rocket without it, but at the same time I dont want to regret things by not learning how to use circuit network in the early game. just like me before not using radar and realize I have to expand my resources further or else my main base gonna running out of raw materials soon

JapaneseMom wrote: Sun Sep 13, 2020 8:56 pm does circuit network can actually combines item? can it also process it to another items, lets say copper plate to copper cable? without the automation machine? because according to the videos I've watched he talked about input and output, and in example say copper plate, multiply by 2, set the output to copper cable, and then the whole network will find any signal with available signal and gives the output according to the setup. now, what i dont understand is this output thingy. what does it actually do? does it produce an actual output? or just gives signal, some kind of reminder, or just showing you the thing the same thing when you press ALT? is it really crucial for me to know how many items I currently have with this circuit network? or is there more to it than that?

The circuit network signals are virtual. They have no meaning outside of the networks made with red/green wire and the ability to turn off inserters/belts/pumps/etc.

JapaneseMom wrote: Sun Sep 13, 2020 8:56 pm because the very very basic setup of circuit network i saw is that it will give you the same information that you get from pressing ALT, except it tells you the numbers of items you currently have also.

While circuit network can give you, the player, some information it can also provide that information to other machines in order to control them.

JapaneseMom wrote: Sun Sep 13, 2020 8:56 pm for practical uses, I think the its useful for electricity because in the tutorial it tells me that I can switch from solar panel during the day and switch to steam machine during the night, means I can save lots of coal instead of relying on it 24/7.

some people on steam forum told me circuit network is optional and I can launch the rocket without it, but at the same time I dont want to regret things by not learning how to use circuit network in the early game. just like me before not using radar and realize I have to expand my resources further or else my main base gonna running out of raw materials soon

Putting it simply: the circuit network is all about stopping something from happening:

• Backup steam: You can use circuit network to stop steam engines from running more than they need to by controlling a pump on the steam tanks.
• Oil cracking: You can use circuit network to stop all your heavy oil from be cracked leaving you without any lubricant by controlling a pump at the heavy oil tank
• Saving nuclear fuel: You can use circuit network to stop nuclear reactors from constantly consuming fuel and only run when needed by controlling the inserters feeding nuclear fuel into the reactors

And so on. By default the factory will always run as fast and as much as it can. With circuit network you can stop/slow down some process. Whenever you have some machine that's doing something too much or too fast then the circuit network can help stop/slow that machine down.

This also means that the circuit network is completely optional. You can just let all the machines run normally without any circuit control. You can let steam engines run as much as they want (or just fully replace steam engines with solar/accumulators in the right ratio). You can directly use the heavy oil of one refinery to feed the lubricant chem plant. You can run nuclear reactors all the time since nuclear fuel is plentiful anyway. And if you ever run out of resources you can just expand further. There's no problem in factorio that can't be solved by building bigger and expanding further.

With the logistics network it's pretty useful to use the circuit network to control how much of certain items are produced. Of course you can just limit a chest to a certain number of stacks. That works, but has the issue that you can't easily put in more than that limit in the chest.

Take yellow belt production for example. You can just limit the output box to 5 stacks of belts. Then when you deconstruct something to replace it with red belt the robots can't put those excess belts in the box, where they could be turned into red belts. Instead you could connect the chest to the output inserter and tell it to only put in belts if there are less than 500. Now you can remove the limit on the box and you can put it more than 500 by other means.


For steam backup power you can use this simple SR-latch:
https://wiki.factorio.com/Tutorial:Circ ... am_example
Though instead of using a power switch I simply switch the offshore pumps


* As said, oil cracking is another obvious application and something I consider a must have there. It's also very simple. Just switching some pumps depending on the fluid level in a tank. For example only crack heavy oil when you have a tank of lubricant
* Uranium enrichment can also be made easier with some simple circuits. But it's not strictly needed
* You can control how many construction and logistics robots are inserted into a network by reading the robot statistics and switching on inserters
* You can turn train stations on and off. This is very useful to supply outposts with repair packs or ammunition. Or to deliver acid to uranium mines. Just have one train go to all outpost and then turn off stations that have enough supplies.

You can do all kinds of other neat things with it, but people are correct that they are entirely optional. You don't need any kind of truly complicated contraptions.