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HomeLED TechWhy LED high bay have different quality, even when they have the same LED driver and LED Chip.

Why LED high bay have different quality, even when they have the same LED driver and LED Chip.

There are many LED High bay products use Meanwell driver and Nichia LED Chip, and all announce that the lamps have a 5 years warranty, but some of them break the first year or second.  How this come?  Chinese LED lighting market are full fill with different looking LED high bay lights,  some of them are 3 times prices than cheapest LED High bay light or more, and all announce that they have 3 years or 5 years warranty just because they have a meanwell driver. this is becoming more and more chaos when the demand is decreasing,  more and more manufactures are going to produce cheaper and cheaper products to meet temporarily profit because they don’t have a 3 or 5 years plan for their company, and just want to sell more and more , maybe vanish in few years, but this is normal in China.

There  are many small LED heat sink manufactures in Guang Dong,  producing these LED High bay kits when they first thinking of ” how to make it cheaper”, but not better and cheaper. this cause a lot quality problems for customers when they start to buy LED High bay lights, cause these lights will be installed at least  6 meters high,  and it cost a lot to get them off beside changing a new lamp for customers.  This break  the market of LED High bay lights, when bad quality LED high bay lights sold by some sales person who knows nothing about this product beside the wattage, lumen and power factor.

Thanks for all professional manufactures or dealers who sell quality LED high bay lights, you help to keep the market growing because of your insist on supply customers long life span LED high bay light.

but how to choose a good LED high bay light?   there are several important conditions matters,  LED drivers, LED Chip,  thermal housing are 3 main points.  then you have optical designs for different places,  water proof and dust proof, etc .

  1. LED Chips and drivers ,   the best choice are branded LED Chips like CREE, Nichia,  and drivers like Meanwell and Philips.  Also other branded LED chips and LED Drivers, but I will compare them in future articles.
  2. thermal housing design

different thermal housing design give complete different heat radiation.  please see Elite™ LED High bay light heat image below

Elite LED High Bay Light thermal housing

after tested, the max housing temperature is 58.2°C, but this is not all.  what we need to focus on is the LED Chip temperature,  as what we all do to cool down the LED Chips to keep long time using.  please see below heat image, the test result under 24 hours continue working with working temperature 30°C to 32°C.


heat image for 150w elitefrom the image, M1-M18 mean the temperature of PCB, HS1-HS18 mean the temperature of LED Chip, from the test:

M1 – M18 value= 61.1°C to 63.5°C,  and HS1 – HS18 value= 69.0°C to 72.0°C .

and after tested the normal heat sink,  like picture show below,

bad heat sink3

M1-M7 velue= 46.3°C to 55.5°C,  the M5, M6 and M7 are the most closest point to LED Chips,  The temperature is Cool.  but let’s see below picture,

 

bad pcb
from the above picture,  M1 – M20 value= 57°C to 66°C,    but  HS1 – HS12 value = 88.9°C to 96.8°C, which is amazing,  the temperature difference up to 30.8°C, Which means the heat from the LED chip, can not be conducted.  The heat all together inside the LED Chip, and the thermal housing did not work well.

and According to the LM80 test of Nichia NF2L757DR,   we see:

LED High Bay Light NICHIA LM80

 

when Nichia LED Chip is working with 100mA and 85°C working temperature,  the lumen decay is less than 3.3% after 10100 continue working hours,  which means 1263 working days if 8 hours lighting time per day.  This means the LED chip is almost zero lumen decay after 3 and half years working.  The actual working power and temperature is 116ma, but only 72°C max,  this is even lower than LM80 testing conditions.  and we will get less lumen decay on Elite™ LED High bay light.

Below picture show when Nichia working under 105°C  and 100mA ( This is the closest data can be found in LM80 tested).

LM80-105-100

From the LM80 test report,  the lumen maintenance is 87.3% to 94.6%, which means the lumen decay is 5.4% to 13.7%,  the worst condition is you get 400% light lose compare to the Nichia LED chip which working under 85°C. and for some bad LED high bay thermal housing , the Max working temperature for LEDs can reach 120°C or more,  which is beyond LM80 test, and can not predict the lumen decay after 10100 working hours.

beside the LED working temperature, the other key point is LED Driver working temperature.  please see below test result:

driver working temperature

on the bottom of the image,  M7=58.4°C, M8=62.2°C, M9=59.8°C,this is highest working temperature for LED Drivers( Meanwell HBG-160), and from the Meanwell official data,  the Diver are with 5 years warranty if the working temperature is below 70°C, and 40000 hours life time.

for both types tested, the LED Drivers working temperatures are about the same, but the temperature on LEDs are with 20°C difference, and for some worse quality LED high bay thermal housing , the temperature difference can reach  30° or more.   This is why the bad quality LED high bay lights’ LED break first or losing light very fast.

from the 2 test and calculation,  with our LED High Bay light,  you can get the minimum lumen decay after 5 years using with warranty.   if you want more information on Elite™ LED High bay light, please contact us:

 

 

 

 

 

 

 

 

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