TL;DR
Some entities like inserters, belts, assemblers can benefit from using conditions with themselves, without any other connected entity. There are certain applications for this like in the examples below. Current workaround: add a dummy entity that does nothing just to enable the circuit network, e.g. a display panel. Connecting to an arbitrary entity nearby is not always desirable due to space restrictions or signal leaks.What?
Unlike Logistic connection, Circuit connection can't be enabled with 0 wires.1) Belt stopping when specific item is on top.
- I have a belt and I want the belt to pause in front of inserters in order for items to be picked up without leaking through.
- Sometimes it is convenient to connect the belt with the inserter, but if the inserter is itself connected to the circuit network with Hold for other reasons (like knowing what items are in the system at all times), this won't work, as the belt will pause when the Inserter picks any item.
- Need a dummy display panel for each piece of belt, since using just one for all of them would cause the belts to cross-contaminate each other.
2) Inserter self-filtering
- I want to output stacked items on a belt, but the source can contain several items.
- I don't want the stack inserter to be stuck waiting for items if there are fewer than 16 in the chest.
- A solution to this is to have the inserter use "Hold" to send a signal to itself, and then Set Filter + Blacklist. This will cause the inserter to drop items even if not reaching full capacity.
3) I want to pause as assembler when too many of an expensive item are made



