There are many factories producing LED tubes on the market, and the quality of products varies greatly. The price of LED tubes is transparent and chaotic. The same specifications are marked by each factory. The price difference is tens of yuan/piece, which is expert and explains clearly to the guests. This huge price difference is not easy. Take T8, 1200MM, 18WLED tube: the price on the market is sold at 50 yuan / support, and some people sell the price to 160 yuan / support, why is the price difference so big? The reason for the different prices is nothing more than the difference in the materials used for LED lamps. Let us explain the three main materials that make up the LED tube - LED light source, power supply, and profile.
One: LED light source: (Generally adopt 3528, 2835, 3014, 3020 as the main light source)
1: The quality of the light source is good and general, mainly based on the chip used as the core reference. The chip has CREE, Osram, Hewlett-Packard (HP), Nichia (Nichia), and other first-line brands, but these chips are mostly parallel imports. It's hard to argue. In Shenzhen, there are not a few manufacturers that will use it. The second-line brands include Epistar, Huga, ChiMei, Genesis Photonics, Tekcore, etc... These chips are recognized by the light source packaging manufacturers as cost-effective chips. Also the most commonly used.
2: LED chip quality judgment: take the size of the chip, such as 7*9mil to 10*23mil for reference, the larger the size, the more expensive the relative price, the better the quality; the level of the chip is as follows: A file, project Products, B-grade products, wafers and other grades of products, the price difference is multiplied to several times (the specific distinction between the appearance and performance of the A product and the special product chip, the insider is also difficult to distinguish, not to mention how to identify In fact, the so-called project, compared with the A product, is a little flawed in quality, but it is not a serious quality problem. But no matter what level of chip, after our hand, we can definitely determine what its chip level is. We are confident that the supplier can't lie.)
In summary: to judge the quality of the chip, we must first look at the chip brand? Then confirm whether the size of the comparison chip is the same or similar, and finally confirm that the chip level is A product? Special product? B file? Wafer? Regardless of the brand, the price of the same grade of chips, the price is actually very small, in other words, whether it is the wafer, Guangcai, Chi Mei, Taigu, New Century chips, as long as the A-class products, the chip size is the same, the quality is There is no difference. The quality is high and low to confirm the accessories used in the LED package , such as the thickness of the silver layer of the bracket? What is the quality of silica gel? The quality of the phosphor? Dispensing process control, etc., judging the quality of the LED light source from the parameters, mainly how high is the brightness? How high is the index? Is consistency good? (by professional instrument testing)
If the light source 3528 used alone has a brightness of 7-7.5LM or more, 2835 uses a dual chip, the brightness is single 15LM or more, and the color rendering index is 75-80; and the designated chip is A product Taiwan Guangmei or Chimei, the size is 9 *21mil or more. The quality of the light source is in the middle and upper grades. In particular, for the driving current of the light source 3528, the normal standard in the industry is 20MA. In order to reduce the heat generation of the LED tube, we sacrifice the brightness of some of the light sources of the 3528, not driven by the full 20MA, and only driven by 17.5MA. Efforts have been made to increase the brightness of a single light source to around 7.5 LM to reduce the "light loss" driven by low current.
In the market, more factories have LED tube light sources, and the brightness of single lamps is also 6-7LM. However, because they do not have the light source packaging capability, when purchasing the light source, they also require 3528 lamp beads to be cheap to 6 cents to 1 cent. The price can only force the relevant LED packaging factory to use a small-sized chip such as 8*15MIL or 10*16MIL or a B-product. 18W lamp 288PCS light source cost only 17 yuan to 28 yuan; middle and upper grade 3528 light source, such as chip wafer, Guangjia, Chi Mei 8 * 20 or 9 * 21 MIL, A product, the price is at least 0.15 yuan / The cost of the light source is 43 yuan / support. The cost of the light source is 18 yuan to 26 yuan per lamp.
Second: the market status: the current market LED tube to 3528, 2835, 3020, 3014 and other specifications
Some factories do not use 3014 light source, mainly 3014 is not good value for money, but why do so many people use 3014 light source on the market? As we all know, the 3528 wattage is 0.0625W / piece, generally driven by 20mA or less, is a low-power light source. 3014 is 0.1W, which is driven by 30mA. It belongs to medium and small power light source. Generally, it is about 10*30MIL for medium and small power chips. The price is more expensive. It costs 100 yuan or more per K. The chip is 3014. The cost is too high. The price is not good, so my factory does not use 3014 as the light source of the LED tube. The 3014 light source on the market is mostly about 120-150 yuan/K. We have dissected the 3014 light source used by many factory LED tubes. The chips used are all low-power chips, such as 8*15 MIL, 10 *16mil, 10*23mil, mainly with 30mA drive, has exceeded the current tolerance range of the small power chip, although the single brightness is about 11LM, the brightness and wattage are pushed by the current, plus the bracket of 3014 The size is originally small, although the 3014 bracket has a so-called "heat sink", but it will be overheated for a long time, the chip will overheat, the light decay is easy to produce, and it is destined to have a light decay problem in the future. . Some factories use such a 3014 reason, mainly a lamp, the same 18W, 3014 light source less than 100, we have calculated that a lamp can save about 20 yuan of light source costs.
Three: Power: The power of LED fluorescent lamps is divided into non-isolated and isolated.
1. Non-isolated constant current power supply: Non-isolated means that there is a direct connection between the load end and the input end, so there is a danger of electric shock when the touch load is applied. The advantage of the non-isolated constant current source is that the circuit design is simple and the manufacturing cost is not high. The disadvantage is that the high voltage of the AC power source is introduced to the load end, which may cause electric shock.
2. Isolated constant current power supply means that there is isolation transformer isolation at the input and output terminals. But both can isolate the input and output. The advantage of isolating the constant current source is that the circuit design is complicated and the risk of electric shock can be avoided. The disadvantage is that the efficiency of the power supply will be reduced, the manufacturing cost is high, and the volume is relatively large.
The price difference between the two types of power supply is large, the non-isolated power supply is 13 yuan/piece, and the isolated power supply is 26 yuan/piece. The quality of the power supply material is explained to the guests, so that the guest can make the most appropriate choice. Many non-isolated power supplies on the market are 6 yuan to 9 yuan / piece, isolated power supply 15 yuan to 18 yuan / piece, some factories use integrated power supply, directly soldered on the aluminum plate, the cost is about 2.5 yuan / piece, so, The price of the power supply is also about 10 yuan.
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