One lumen is the flux emitted into one steradian by a source of one candela. At 555 nm, where the eye is most sensitive, one watt of radiation equals 683 lumens; at other wavelengths it is fewer. As rough benchmarks, a household 60 W incandescent gave about 800 lm and a typical 2x4 LED troffer delivers 3,000 to 5,000 lm.
Spec says 800 lumens minimum per pendant, and these cut sheets show delivered lumens, not source lumens, so we're fine.
Also heard as
- lm
Related terms
Luminous flux
The total amount of visible light a source emits in all directions, weighted for the eye's sensitivity and measured in lumens.
Candela
The unit for how much light a source throws in one direction, and the SI base unit behind lumens and lux.
Lux
The metric measure of light landing on a surface: one lumen falling evenly on each square meter.
Luminous efficacy
How many lumens a light source or luminaire produces for each watt of electric power, in lm/W.