4WD Lights Explained: Lumens, LUX & Wattage
When you're shopping around for lights for your vehicle, the technical terms used can get confusing. The most important part about a 4WD light is the light's intensity and distance.
There are thousands of different makes and models of LED light bars, spot lights, work lights etc. in the market today.
Before buying a 4WD light, do your research on it's specified lux and lumen ratings and work out whether it will suit your application so that you don't purchase a light that is to dull or too bright for the job.
Below, we're going to run through the differences between lux, lumens and wattage.
What are lumens?
Lumen is a unit of light, which is also known as Luminous flux.
We use lumens to compare the total amount of light output from a light emitter (light bar, spot lights etc). However, lumens isn't the be-all and end-all. In fact, lumens will only tell you one part of the picture because when it comes to producing a great beam pattern, it doesn't give you enough information to tell you how the light output is used.
What is lux?
Lux is a unit of light measurement where the area is also taken into account.
1 lux equals 1 Lumen/m2, in other words - light intensity in a specific area. Lux is used to measure the amount of light output in a given area - one lux is equal to one lumen per square meter. It enables us to measure the total "amount" of visible light present and the intensity of the illumination on a surface.
1 lux is the most common measurement of lux as it is the maximum distance a newspaper can be read. 1 lux @ 500 metres means that you could read a newspaper 500 metres away from the light source (light bar, spot light etc).
Watt is a unit of power consumed.
The more power a light emitter consumes, the more lumens it should produce. However, the relationship is non-linear and we can use the numbers from wattage and lumens to measure the efficiency of a light emitter. LEDs have far outpaced the industry as the most efficient light emitter and can produce more light than older halogen lights. One thing to note is the more power is consumed, the more heat is produced, which is wasted energy.
So, what's more important?:
The difference between lumen and lux is that the lux takes into account the light's intensity at a distance. Lumen on the other hand is measured at the light's source, and not at a distance.
While higher lumens is never a bad thing and shows you the light out put from a light, it does not explain to you the intensity of that light at a distance. When you're buying offroad lights, you want to know how far a light can reach, which is why lux is more important.