Most of customer they don’t know about Lumen/lux but most of them inquiry watts, but we educate our clients what is the Lumen, in order to save the energy and reduce cost best for choose the Lumens.
1.What is the relationship and difference between Watts and Lumen?
Wattage, indicates how much electrical energy the lamp would consume in one hour.
Lumen, measures the total amount of light emitted by the lamp, this will directly matters how bight it is.
I hope you can understand that its not higher wattage but its higher lumen which is the key factor to decide the lamp is brightness or not.
With the popularity of LED and the continuous development of the industry, now we have more efficient products, we can get very high lumens per watt which is almost double so save energy and get more brightness than high wattages
for eg. 10 watt can give 1000 lumen and 15 watt can give 1500 lumen but with better led and optics even 10 watt can give 1500 lumens.
Below is the comparison of our 165lm/w high bay lamp with other lower lumen efficiency lamp, it can save you electric bills and be friendly to the environment:
2.What is the relationship and difference between Lumen and Lm/W?
Someone would say there is something wrong there even yet! Lumen is important, but Lumen/watt is more important.
1. Lumen is for the complete fixture
2. Lumen per watt is the light efficiency to decide how much the lamp is evergy saving and how much electricity fee it can save for you under the requirement of same brightness.
So when you buy a lamp, first you need to know how many lumen you would need, then you can compare the light efficiency of lumen/watt to choose the right one. With higher lumen/watt, the lamp would consume less power energy.
Below is the real IES test result of our S5 led high bay with more than 175lm/w:
3.What is the relationship and difference between Lumen and LUX?
Lux, refers to the luminous flux of visible light received per square meter, the direct illumination on a surface from the lamp, equals to lumen per square meter at a certain distance.
Lux is related to the distance of the light source, which directly shows how bright your work table or floor will be
Lumen is a total amount of light emitted from a light source in all directions
From the feeling of end user, LUX is the most direct reflection of the lighting effect to check whether it is bright enough or not.
However, Lumen of a lamp is easy to test with IES test equipment, while it is not easy to get LUX result before installation. As for LUX, it needs to do simulation to get the LUX result, build virtual scene, with professional optical simulation software, such as DIALUX, need accurate lamp IES light distribution files.
And there will be some differences between the simulated results and the actual results after installation, because there are many factors that can affect the results in the environment.
To put it simply, LUMEN simply refers to the total light amount emitted by the lamp, LUX refers to the light amount at a certain point after installation
4.What is the relationship and difference Foot candles and LUX?
Foot candles is the lighting delivered to the zone.
Believe it or not, foot candles are the most common unit of measure used by lighting professionals to calculate light levels in businesses and outdoor spaces. In a nutshell, a foot candle is a measurement of light intensity and is defined as the illuminance on a one-square foot surface from a uniform source of light.
While lumen measures the amount of light created by a lighting fixture, foot-candles is a measurement of the amount of light that reaches a surface area.
Just like feet and meters are both used to measure length, foot candles and lux are both used to measure how much light is emitted onto a surface.
The main difference between the two is that an FC is a measurement used in the imperial measurement system whereas a lux is used in the metric system.
Use of one term or the other will typically depend on the set you are working on and where you are in the world. Some sets may use the imperial measurement system while others use the metric system.
5.What is the relationship and difference Luminarie Lumens and LED Lumen?
To buy fixture lumens, not LED lumen!
Several factors can affect the overall Luminarie Lumen
A. Light efficiency of light source(LED)
B. Lamp lens transmittance(generally 87%~93%)
C. Heat dissipation condition (that is, heat loss, in high temperature, the light efficiency will decrease)
D. Drive efficiency
6.What is the relationship and difference PFC and Watts?
Lumens and watts are very important, but is there any other important factors that needs to check when buy a lamp? -Power factor (FP),
There are “quite bright” Luminaries but they are inefficient as they have a very low power ratio necessary to convert energy into light.
Power Factor is the ratio of total power flowing through the circuit load to the lamp power. The closer the Power Factor is to unity (1), the more efficiently it would be.
A lamp with a bad power factor is going to be inefficient, will put an unnecessary strain on the grid, and possibly cause problems to the rest of connected devices
Eg. the lamp power is 100W, with PFC 0.9, the total power consumed in the circuit would be 111W; with PFC 0.6, the total power consumed would be 167W. This is directly related to how much you have to pay for electricity.
So choose a lamp with good PFC is energetically and environmentally more important, save energy and save money. In nowadays, most of led lamp PFC can be higher than 0.9, ours even can be 0.95.
7.One more: qualtity-duration
A good quality lamp can save you from trouble with maintenance and replacement. So first, you need to check the warranty terms. And also the lumen depreciation.
Some products at the beginning the lumen might be very high, but it might break down in a short period time. Then you have to add more lamps or even replace all of them to more efficient ones.
So the lamp with a high lumen/w and the ability to control same play within the working life is a far more relèvent issue in saving energy and money over time.