Lumen/ Watt
Used to measure LED light bulb power consumption.
Lumens describe the ''brightness'' of a led light, "wattage" describes the power it takes (on your utility bill) to drive that led lamp.
In general, however, a higher wattage lamp will normally produce more light (more lumens) than a lower wattage lamp OF THE SAME TYPE. The unit for measuring electrical power. It defines the rate of energy consumption by an electrical device when it is in operation.The energy cost of operating an electrical device is calculated as its wattage times the hours of use. In single-phase circuits, it is related to volts and amps by the formula: Volts x Amps x PowerFactor = Watts.
LED's use about 1/5 of the energy of their equivalent incandescent flood replacement and 1/2 of their equivalent compact fluorescent (CFL) replacement.
Please note:LEDs have a lumen to watts rating
LED bulbs: 70-80lm/W
CFL bulbs:50-70lm/W
Incandescent bulb:5-6lm/W
The measurement of that light energy is the lumen (lm). Simply put: lumens are the measure of the total light output we see. This 'brightness' is now required to be listed on light bulb packaging. Lower numbers are duller and higher numbers are brighter.
When purchasing light bulbs the best measure to determine suitability is the lumen.
LEDs have a lumen to watts rating that far surpass incandescent bulbs and even have better ratings that compact fluorescent bulbs (CFLs).This means that an LED light will cost you less in electricity and still shine bright.
Typically used to measure the light intensity produced by a lighting fixture. The higher the lux reading the more light the lighting fixture is producing over a given area. Known as lumens per square meter.