Redstonery
Redstonery › Circuits › Container full alarm
Detection circuit

Container full alarm

Detect a high inventory boundary.

6 × 2 footprint1 layer7 blocksTested in 4 rotationsJava Edition 26.2
Open in the simulatorBuild it in the game

Layout

Layer 0 (on the floor)
barrel at x 0, z 0comparator [facing=west, mode=compare] at x 1, z 0redstone dust at x 2, z 0comparator [facing=west, mode=compare] at x 3, z 0redstone block at x 3, z 1redstone dust at x 4, z 0redstone lamp at x 5, z 0
redstone dustrepeater or comparatorlampcontainerredstone blockarrows point where a device sends its output; north is up

How it works

A comparison against a side strength of 15 activates only when every barrel slot is full. Removing even one stack clears the output.

  1. The comparator supplies a fullness level.
  2. A reference or signal-length boundary identifies the design’s full or near-full condition.

Inputs and outputs

  • Inputedit barrel contents (x 0, y 0, z 0)
  • Outputalarm (x 4, y 0, z 0)

Blocks you need

2 × comparator, 2 × redstone dust, 1 × barrel, 1 × redstone block, 1 × redstone lamp.

Build it in the game: 7 commands

Relative to where you stand, with x running east and z running south. Paste one line at a time into chat, or into a chain of command blocks. The block art is the game's own; the layout is what the page above shows.

setblock ~0 ~0 ~0 minecraft:barrel
setblock ~1 ~0 ~0 minecraft:comparator[facing=west,mode=compare]
setblock ~2 ~0 ~0 minecraft:redstone_wire
setblock ~3 ~0 ~0 minecraft:comparator[facing=west,mode=compare]
setblock ~3 ~0 ~1 minecraft:redstone_block
setblock ~4 ~0 ~0 minecraft:redstone_wire
setblock ~5 ~0 ~0 minecraft:redstone_lamp