Which LED I should choose? How do I know what is good and what is not? How different is "LED bulb" for 20 PLN from the one for 150 PLN? Is it just matter of marketing?
After years of gaining experience about diodes, LED lamps and lighting market we feel up to it, to write an objective article - guidance on the evaluation of the profitability of buying a variety of different LED lighting products.
Let's start than.
We'll focus on products that are relatively simple to compare - light sources based on LED lights - often called LED "Bulbs".
On the market there is a lot of types of LED light components: handles, diodes, etc. They got different power, durability and manufacturers. How to choose right one?
Enclosures
We are dealing with low-cost "heat sinks" made of plastic, as well as beautiful (technically) aluminum or even aluminum–copper constructions - which perfectly receive the heat from the LEDs to bring them back to the environment. (What is the relationship of heat from LEDs - you will find HERE.) You can also meet designs that are pure imitation - as if someone wanted to do a cooling cover but did something wrong. It has aluminum radiator, but heat transfer from the LED elements to the heat sink is very impaired. This type of heat sinks works better than plastic but the result is only a longer agony of LEDs. Whole product will also stop working soon. On the first sight - it is very difficult to identify such a structure. There remains a commonsense approach stating that the product is usually worth so much, how much it costs.
Diodes
You can meet with specimens of trash that shine light of weird colors - certainly not white, as well diodes emitting white light, indistinguishable from incandescent light. There are also elements glowing nicely, but for a very short period of time. The color itself is one thing, and that is what we will see in that light is another thing. Manufacturers of cheap LEDs have here a large room to maneuver. Ratio of color reproduction (CRI Ra - with a maximum value of 100, for the sunlight) is the size of noticeable to the eye, but difficult to measure. In a word - only after some time of use it gets out that you installed a light that looks "strange", in which the colors are hardly distinguishable, and can often be mistaken. Professional users for whom color accuracy can be crucial should be especially aware. We mean here: hairdressers, cosmetic stands, clothing and footwear stores, stands with vegetables and bread, graphics studios and all other places where color accuracy is a matter not to be missed. It is obvious that the higher the color rendering (richer spectrum of light) is, the higher would be the price. In cheaper products you will never find high CRI. You have to assess whether you need a high CRI in your application or not. Note that CRI factor is not equivalent to color of the emitted light.
Power converters
Also here - you can buy flickering bungling at which after one hour your eyes hurt like in front of like the spherical monitor in the 90s (God forbid use something like that in place where you work or rest) or a source of stable glowing light, where it is a pleasure to read or watch a movie with a glass of wine. The converter is often the weakest link in the whole system. It is not easy to create highly miniaturized inverter power supply, which also will offer high performance and durability at a low price. These values are closely related and usually grow together. You can find LED, which are relatively cheap and trouble-free but it shines a bad light.
Summary
There is no one rule that says what to buy, or says that the product of dubious quality and low price is bad for us, and the expensive - good. As in many other areas – you must first define our requirements and determine whether the use of high quality is so desirable that you were willing to pay a higher price.
If you decide to buy "economic" source of light – you will realize that sources vary in color and intensity of light. What is more you will need to be replaced them often with new ones as a result of damages / defects. Is it profitable? - You should assessed it individually.
Our observations say about the following price ranges for 5-6W bulbs:
- Up to 20 PLN -> most of them are low quality "Plastics". Poor light, fatal durability, lack of reproducibility, often break up in the hands just after it is removed out of box. We often joke, that this type of bulbs "degrade already in the catalog". If you see aluminum here - you found a great sale or mere imitation.
- From 20 to 50 PLN -> aluminum casings of various stripes. Mainly we see here economical LEDs having problems with color reproduction and repeatability. Sometimes you can meet a nice white color of the emitted light. Unfortunately, there is no guarantee of long maintenance of that color. Durability converter - only sometimes you can find something good - usually from the top of that range.
- From 50 to 100 PLN -> Models worth of interest. Typically, the best ratio of price / quality. Often used LEDs from renowned manufacturers. Color reproduction index does not allow to distinguish them from incandescent and fluorescent sources. Usually very good durability and lifetime maintenance of light color. It is good to choose models with external power supply (definitely confirmed). This greatly improves the life and improves the working parameters. Do not cling to LEDs power given in watts, but pay attention to the real efficiency of the LEDs used. You can check productivity by dividing the luminous flux (lumens) by the power (watts). The higher the value, the better. 80lm / W is already obsolete. Now standard is around 100lm / W. In most cases it is the best choice for residential and commercial usage. Warranty will never go below two years, and in the upper price range - is 3 years or more.
- Above PLN 100 -> models usually for professional use. CRI usually exceeds 90, a lifetime is obviously a huge and often difficult to predict. The color of light unquestionably perfect and reproducible.