Led lights are usually the first choice when we choosing lighting products, so it is useful to know the performance of LED lighting products.
The product specifications of each manufacturer are quite different, the luminous efficiency of LED lighting products is usually between 601m/w to 1001m/w, color-rendering index is usually between 60 to 90, color temperature is usually between 2700k～6500k and the life of the products is usually between 20,000 to 50,000 hours. So how should we choose?
1) Choose a high Lumens / Watt led lighting product
Luminous flux, the total amount of visible light that emitted by a light source per unit time, unit: lumens (lm).
Luminous efficiency, the light energy that generated by the light source per watt (commonly known as luminous flux), unit: lumens / watt (lm / w)
The luminous efficiency of a LED lightning product is the number of total luminous flux divided by the total power consumption in conditions of rated voltage. The higher number of the luminous efficiency, the better energy saving effect of the LED lighting product. At the same power, a LED lighting product with high luminous efficiency has a large luminous flux, which means the product is brighter and more energy-efficient.
2) Choose a product with high color-rendering index
Color-rendering refers to the proximity of an object to a true color when it is illuminated by light. The larger “ra” number which is the unit of the color-rendering , the closer this object is to the true color. We generally considered that 80 to 100 is an excellent color-rendering range. 50 to 79, acceptable. If the color-rendering is less than 50, than we treat it as poor color-rendering.
3) Choose the color temperature by personal preference
The unit of color temperature is Kelvin (K), the color temperature of red light source is about 800 to 900k, the color temperature of yellow-white light source is about 3000k, white light is about 5500k, and blue light is between 8000k-12000k. theoretically speaking, users can choose LED lighting products with any color temperature, as long as they feel comfortable. People who prefer warm light, they can choose color temperature around 3000k. Those who prefer daylight color can meet the requirements between 5000-6500k. If users prefer cold color light, then choose color temperature between 8000k-12000k.
According to Kelvin’s definition, color temperature between 2800-10000k belongs to the range of sunlight color temperature. However, only light with a 6500k color temperature (also known as d65) is defined as the standard color temperature of white light.
4) Choose LED products with less luminous decay but more luminous flux
Luminous decay is the process in which the luminous flux of a light is gradually attenuated until the exhaustion. It can be understood as the process in which the brightness is gradually attenuated after using the LED lighting product for a period of time.
Lumen maintenance rate is a little bit difficult to understand, it is a ratio of luminous flux value of a LED light that has been lit for 100 hours ( this is also be called initial value) to the luminous flux of a LED light that has been lit for 2000 hours. Lumen maintenance rate is a concept that to measure the luminous decay.
The general explanation is that the brightness of a LED lightning product will decrease after being used for a while. The higher the lumen maintenance rate, the less attenuation of the LED lighting product.