How to quickly determine the quality of LED light - LED bulb
I think this situation will be happened to every buyer ,many people may be attracted by this cheap price ,but in another side,we also afraid too low price will cause product quality to descend seriously, what to do? How to simply identify one LED lamp ?This is a big topic, after all, there are so many kinds of led light, so let's start with the LED bulb.
As the biggest export quantity of LED light ,there is no doubt for LED bulb,but it’s not easy for technological requirements.As the size of bulb is small,all the heat is concentrated in the cavity body, once the cooling and temperature control is not good, the whole lamp will be easy to appear dead lamp and light failure too fast, especially more than 7w bulb light.
As the biggest export quantity of LED light ,there is no doubt for LED bulb,but it’s not easy for technological requirements.As the size of bulb is small,all the heat is concentrated in the cavity body, once the cooling and temperature control is not good, the whole lamp will be easy to appear dead lamp and light failure too fast, especially more than 7w bulb light.
Lets take this inferior bulb and elegentlight bulb for example,we will see the difference:
1.Power supply part:
When you got one driver first check three points: driver design,wiring and electronic materials.
①Power supply solution
From the LED development to the present, domestic power supply plan after a lot of practice and perfect, although there are some gaps with the IC in foreign countries, but basically can meet the ordinary production needs.So, in terms of options, the difference is not too big (if you use a regular new material, not a recycled material or an unknown IC.
From this two photos maybe can’t see IC item No,but at least you can know the solution of this two type are both IC switching mode power supply.So only check the solution of this two type ,it’s almost no big different.
②Lay out
Layout of wiring can be directly decided the quality of power supply.A good electronic engineer when do the wiring, not only should follow the basic principles of wiring, and combining with the production process to avoid a lot of bad situation (such as many power panel surface residue in the production of some tin slag, lead to high voltage when it is easy to produce electric spark).Except this,Also consider heat dissipation.We know that on the LED power supply board, IC and the transformer are the main source of heat, the electrolytic capacitor is most easily affected by the temperature and cause short life of the components, so the reasonable wiring, the heat is necessary to spread out as far as possible.
Both driver wiring are reasonable in the front side,However, elegentlight's power panel has a large number of copper cladding and is attached to the IC hole on the back side, so it has an advantage in heat dissipation.①Power supply solution
From the LED development to the present, domestic power supply plan after a lot of practice and perfect, although there are some gaps with the IC in foreign countries, but basically can meet the ordinary production needs.So, in terms of options, the difference is not too big (if you use a regular new material, not a recycled material or an unknown IC.
From this two photos maybe can’t see IC item No,but at least you can know the solution of this two type are both IC switching mode power supply.So only check the solution of this two type ,it’s almost no big different.
②Lay out
Layout of wiring can be directly decided the quality of power supply.A good electronic engineer when do the wiring, not only should follow the basic principles of wiring, and combining with the production process to avoid a lot of bad situation (such as many power panel surface residue in the production of some tin slag, lead to high voltage when it is easy to produce electric spark).Except this,Also consider heat dissipation.We know that on the LED power supply board, IC and the transformer are the main source of heat, the electrolytic capacitor is most easily affected by the temperature and cause short life of the components, so the reasonable wiring, the heat is necessary to spread out as far as possible.
③Electronic materials.
The price difference of the power supply plate mainly focuses on the material, and the quality of the materials directly determines the life of the power supply.In order to save cost, many power plants have used the materials and recycled materials to serve as the main material, resulting in a very unstable power supply.The photos of these two power sources should be obvious to you, especially capacitors and transformers.
2.PCB Board
The price difference of the power supply plate mainly focuses on the material, and the quality of the materials directly determines the life of the power supply.In order to save cost, many power plants have used the materials and recycled materials to serve as the main material, resulting in a very unstable power supply.The photos of these two power sources should be obvious to you, especially capacitors and transformers.
2.PCB Board
①LED lay out
LED SMD wiring generally follow the layout is mixed serial and parallel principle, now in order to reduce cost and control the heat, the mainstream design is to reduce the power of output current as far as possible also under reasonable design conditions .
Look at first PCB board,we can see that the LED is designed all in series.The advantage of this design is that the output current of the power supply is very small, which can save some cost for the power supply.But this kind of design has a fatal flaw, once a led appeared problem, so the whole light is not bright, although now the led encapsulation technology is more mature, but it is always a risk, so as long as it's not extreme cases, general factory is not going to use this design.However, the second board adopts the line of 2 series 8 parallel, which takes into account the risk of the lamp and the cost of the power supply, which is obviously better than the first one.
② LED as the main heat source of
LED positionwholelight,where is the highest temperature of an LED lamp? Yes, on the led of the lamp, and the temperature of the led will be transmitted to the lamp board through the soldering disk, so it is necessary to make a proper lamp arrangement.
The first lamp board, the led all are on the edge of the lamp board, result is the temperature of the edge is too high, and the temperature in the middle is low, cannot form the effective heat conduction.The second lamp is relatively uniform, and the design is more reasonable.
③The quantity and power of LED
In the case of the output current is under certain circumstances , the quantity and power of the led determine the power and efficiency of the whole lamp.Why we say that?Take these two lamps for example:
First check the elegentlight board,totally 16 led SMD, each power is 1w.In order to make the whole light power is 12w ,that each led around 0.68w is the actual use of power, and we know that the led power efficiency is highest in about 70% of the rated power, so the lamp must be high light efficiency as a whole.
Lets see another board, 14 leds, suppose that each of the rated power is 1W, if the lamp is full power, the power of the single power is 0.77 W.Looks good right, but we see from screen printing on the lamp panel, the lamp is A60 caliber, and there is no cooling medium plate, if we make full power, the whole lamp heat dissipation structure can't afford to support, it is easy to dead , and light decay will be very fast.Therefore, through the picture we can speculate that this lamp is not full power, and the single power of the lamp bead is only 0.5 W, and the power of the whole lamp is between 7w-8w.
3. Structural parts
There are more discussions about structural parts: out body material,transmittance of PC cover and so on,we still compare with this two bulb and see .
①Middle heating panel.
Comparing the two structures, it is easy to find that the first lamp significantly reduced a thermal conductivity plate.We tested similar structure, found that the designed cooling are a problem, a lot of heat focus on lamp plate , can not be effectively conducted to lamp cup,then it will lead to serious decay of the whole lamp even under the normal working environment.
②Body material
Both are the structure of plastic and aluminum, but the appearance material is different, the first is the ordinary plastic material (see color is likely to be recycled PC material), the second is thermal conductivity PC material.We know that the shell structure itself is the better, the bigger the diameter, the better the heat dissipation.Obviously, the second one is in the best interest.So I'm going to give you a little bit of the diameter and the corresponding power of this kind of structure.
A50---3W
A55---5W
A60---7W
A65---9W
A70---12W
A80---15W
A95---18W
These are the optimal cost performance data obtained based on the strict long time test of elegentlight, testing conditions
Temperature:80℃
Relative humidity:90%
Time: 1440hours continuous lighting
Voltage:220v
Aging test results: lamp beads haven’t obvious sulfide (blackening), light decay < 20%, color temperature is less than 1000K.
③Transmittance of the PC cover
In Luminous Flux Of LED Lights , we know the usage and difference Of the light mask
The first light mask is black, and it is clear that the light transmittance will not exceed 65 % (the material is estimated to be recycled PC material or PS material), while the second one is obviously white, and the transmittance is 83%-86% after testing.Only based on this one, the light flux is going to be a difference about 150 lm.
With so much analysis, we can basically judge the parameters of the two lights. After reading this, we can find out why this 12W is so cheap.The basic good 5W bulb is brighter than it, and the quality is even better.
| Item | Diameter | Driver | Power | PF | Lm/w | Lumen flux |
| No.1 | 60 | Non-Isolated | 7-8W | 0.5 | 65 | 500 |
| No.2 | 70 | Non-Isolated | 12W | 0.5 | 95 | 1100 |
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