How do circuit networks function?

[Nanako]

In a tutorial i saw someone make a chest with an inserter that would only take things out if the chest had more than X contents. But how does this work?

All i know is it's something to do with circuits, i've poked around a little and can't immediately see how these are supposed to work. i connected a chest to an inserter, and could see all sorts of items and a constant field as conditions. but not sure what to do with them

give me a quick primer please!

[Coffee Daemon]

Sure. So wire from inserter to chest. The network will read the contents of the chest. Simple enough.
The inserter Can be set to either not use the network, use t's own conditions, or use the network itself to tell it what to do. You'd want the middle one.

At the bottom you'll see a Enable Condition. This means when this is true, work (a.k.a. move items out the chest).

If you are storing coal in the chest, and the inserter's Enable Condition says "[coal symbol] > 50" that means it will turn on only when there is more than 50 coal in the chest. < would mean less than. = is self explanetory XD Most useful for if you want a little spare, but dont want to waste a whole chest on somthing.

[Ame]

The boxes on the bottom when you clicked on an inserter connected to a circuit network is the condition that will enable the inserter. The chest, assuming it's connected to the same network (fyi: connecting an inserter directly to a chest is still a circuit network, merely a very small one), will output signals that match the chests contents. For example, if a chest connected to a circuit network has 1k express belts in it, then it will send a signal of 1k express belts to the rest of that network.

Lets keep with the belts example and make a intermediate resivoir chest (my name for it, others might know it as something else). We have a chest with an inserter going into it and one pulling out of it. The thing is, we want some number of fast belts in that chest that is less than the maximum amount we want in the chest; I'll use at least 100 and a maximum of 500 for this example.

Now, follow these steps to set it up:

1) Use red or green wire (doesn't matter which) to connect the incoming inserter to the chest and then the chest to the outgoing inserter. If you did it right, you should see a wire of the appropriate color between the chest and each inserter; as well as having the additional options when you click on either inserter.

2) Now it's time to set the limits. We'll start with the incoming inserter; click on it. Make sure the button for "Enable/Disable" is x'ed (it should be by default, but it doesn't hurt to check), and ignore the section about reading hand contents (you can do some cool things with that part, but let's keep it simple for now). At the bottom of the popup window, you should see two large boxes on either side of a smaller box; this is the condition that must be true for the inserter to work. Click on the first box and set it to fast transport belt; this will tell the game to look at the network for a fast belt signal. Now click the other box, you should see a similar window as when you clicked on the first box; this time you want to set a constant of 500, which you can do at the bottom of the selection window (don't forget to click the "Set" button, or else the number won't be saved). Finally, click the smaller box between the other two, a drop down list will appear showing a number of comparison symbols. Click the "Less than" symbol (it looks like this: < ). In words, those boxes say "The inserter can work as normal as long as there are fewer than 500 fast belts in the network (Read: chest)."

3) Now for the other inserter, which will be similar to the first. Make sure the "Enable/Disable" option is x'ed, and set the first box to be fast belts. Here come the differences: set the 2nd box to a constant value of 100, then set the middle box to the greater than symbol (looks like this: > ). In words, those symbols say: "The inserter can work as normal as long as the number of fast belts in the network is more than 100."

4) Chech your work; ensure the inserters are situated properly and build the supporting systems to build red and blue belts. Then, watch the inserters to make sure they are working as intended. You should see the outgoing inserter not moving until the chest holds more than 100 fast belts. Then, you should see the incoming inserter stop once the chest holds 500 red belts. This system ensures that no matter how high your demand for blue belts is, you will always have at least 100 red belts in case they are needed.

This is just the beginning of what you can do with circuit networks, go experiment and have fun. Hope this helped.

[Nanako]

hi, thanks for the replies, apologies for slow response. Ive been experimenting and i think i have the hang of it, but another question has come up:

http://i.imgur.com/tWmzXcF.jpg

Here we see a line of chemical plants processing petroleum into solid fuel. This is wasteful i know, but i have lots of the stuff.

What i'm trying to do here is to set things up so that these plants process away any extra petroleum, based on the level of that tank above.

http://i.imgur.com/euHrIBW.png

This condition in the power switch works perfectly, it turns off when the level drops too low.

But the power switch turning off doesn't seem to actually affect the connected substations. I'm not really getting how power switches work.
Also turning off power in general, feels like a hacky method, but I can't seem to find a way to connect to the chemical plants directly. the wires wont attach to them, it just opens the menu instead

any assistance would be appreciated

[Killcreek2]

Power switches are used to connect two separate electrical networks together, or cutoff the supply between them.

Eg: http://i.imgur.com/KgjwEFw.png?1

The main power supply network is coming from the right [big pole], going through the power switch to the assembly lines beyond, via the med pole & substation.
This is the only power connection between the two areas, so the switch can interrupt it when needed [or triggered automagically by a circuit condition].

<edit> Hold a piece of copper wire in your cursor, and L-click the power poles then the side of the switch. You can also use this to remove cables automatically placed with poles.

<edit2> Personally, I prefer to place a pump on the input pipe to the block, and connect that pump to the tank circuit, so enabling the pump allows the chem plants to operate when desired by giving them fluid to use. Like this: http://i.imgur.com/JGPhuLN.png?1

[Nanako]

thank you :D The pump solution is waaay better than what i was trying to do, thanks!

[Killcreek2]

Yw. <3 pumps.