Factorio Forums

Hello,

Would anyone mind posting a comprehensive description of splitter behavior as of the latest version? I can't do one myself because I'm travelling and away from the game. Thanks!

My hypothesis for version 16.36 is that a splitter has an internal input and output priority (an independent priority for each belt lane unlike the one you can set, so basically two splitters, one for each lane), both initially set to the right belt.

If the belt has two inputs available and two outputs free, it will move the Input Priority belt to the Output Priority belt and the vice versa, and the priority will remain the same.

If it can only move one item, because one input is empty, or one output is full, then it takes or gives to the belt with priority first. Then the splitter sets the priorities to the belts that didn't get used.

Example: Right -> Right priority. Left and Right inputs available, but Right output is full, it can't do Right -> Right, so it does Right -> Left. Priority becomes Left -> Right.
Example: Left -> Right priority. Left input available but no Right input, Right output is full, it does Left -> Left. Priority becomes Right -> Right.

Setting the splitter priorities prevents the internal priorities from changing. While a splitter starts with Right -> Right, setting the priority will change this, even if the priority is disabled again