Lux

Checks whether ambient-light (illuminance) sensors fall inside a lux range, such as: "the lounge is dark", or "the office is brighter than 300 lx".

This is the natural condition for daylight-aware lighting: instead of guessing from the time of day or the weather, it reads what your light sensors actually measure. It is used with sensor entities whose device class is illuminance.

When you add a Lux condition to a scene, the editor shows (top to bottom):

• Any of or All of — shown above the sensors once you pick more than one. "Any of" passes when at least one sensor reads inside the range; "All of" requires every sensor to match.
• Entity — a picker listing your illuminance sensors. Pick one or more. Leaving it empty makes the condition match anything (no constraint).
• is / is not — whether each reading must fall inside the chosen range (is) or outside it (is not). "is not" inverts the whole test — the band and the Any-of/All-of quantifier — so Any of (hall, landing) is not Dark matches when neither sensor reads below 10 lx.
• Range — either a named lux range (see below) or a custom inline band with a Min and/or Max in lux. A band is half-open: it matches when min ≤ reading < max. Either bound may be left empty for an open-ended range.

A sensor reporting unavailable, unknown, or a non-numeric value never counts as inside or outside a range — it is treated as unobservable, so neither is nor is not passes on it. An "is not bright" test will not fire just because a sensor dropped offline.

Examples

Setup	Meaning
Lounge sensor, range Dark	The lounge reads below 10 lx.
Office sensor, min 300	The office is at 300 lx or brighter.
Office sensor, is not, range Dark	The office is reading, and not dark (≥ 10 lx).
Hall + landing, Any of, range Dim	At least one of the two reads 10–50 lx.

Named lux ranges

Ambience ships five built-in ranges:

Range	Band
Dark	below 10 lx
Dim	10 – 50 lx
Normal	50 – 300 lx
Bright	300 – 1000 lx
Very bright	1000 lx and above

You can change these, hide them, or add your own in the panel's Settings → Conditions tab → Lux ranges. Scenes that reference a named range pick up any later edits to it automatically.

Next: Occupancy.