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What's corn bulbs?

Views: 1     Author: Rebecca     Publish Time: 2017-12-15      Origin: Focus Lighting Manufacturer

Brief Introduction of LED corn bulbs

As we are familiar with led bulbs, led flood light, led tube, led panels and so on. How about led corn bulbs?

Today, we will introduce what is led corn bulbs, why design led corn bulbs? Corn bulbs application, advantages and some technical problems.

  • What is led corn bulbs?

LED Corn Bulb got its name because of its resemblance to an ear of corn.

  1. Corn head is the lamp holder.

  2. Corn grain is the SMD chips.

  • Why corn bulbs to be designed?

Corn bulbs designed by Mr. Yang which is an Chinese engineer in 2010. His theme is to create a new, unique bulbs under the same function to replace CFL. 

As we all know that in LED area. Heating and lifespan is the most predators.

Heating will determined by the design of the lamp body. Led corn bulbs design maximize use of air convection to solve the problem of heating.

The lifespan of the driver is determined by solutions.

But what’s solution of drivers? A power solution just like a game rule that takes advantage of each component, while at the same time limiting the life of them.

Some drivers will use top-level components, but it cannot show characteristics of each materials, then lifespan is limited.

Some showed, but the materials cannot reach driver’s requirements. It also failed. 

Lifespan would be longer only combine both of them.

Of course, cost is also most important for engineers when we design corn bulbs.

  • Led corn bulbs application:

At the beginning, led corn bulbs is to replace CFL, so mostly indoor use. We called them household lamps. Such as installed in Hotel, House and so on.

With the widely accept of led corn bulbs, it gradually extended to the outdoor use. Mostly replace MHL/HPS, HID, HQI.  IP65.

Widely used in parking lot, street, courtyard, warehouse, supermarket, lawn and square.

Installed in post top, shoe box, high bay, wall pack, canopy, cobra head, bollard fixtures.

  • LED corn bulbs advantages:

  1. Beautiful appearance, Universal mounting position/ 360degree beam angle.

  2. Unique heating design

  3. 3-5 times to replace MHL/HPS, HID.  7-9 times Incandescent lamp equivalent. 2 times to replace Fluorescent.

  4. 150 lpw ultra-high High efficiency 

  • Led corn bulbs technical challenge:

8w-150w corn bulbs can be offered in market. But 60w is an boundary of corn bulbs. Technical for Internal drivers and heating below 60w is mature. But there are more challenges above 60w corn bulbs.

  1. Heating for Internal drivers above 60w corn bulbs.

  2. Most of factories use aluminum body for heating, but it’s heavy. Especially for high power led corn bulbs.

  3. Led corn bulbs are widely used for Urban Construction. Under the quality of them, should be choose cheaper and more reliable materials? Cost control challenge us all the time.

  • Certificates for LED Corn bulbs

North American: ETL  UL1993&8750.   UL1958c.   DLC 4.0,  DLC4.3  

Mexico :NOM

Germany:VDE   ENEC18/   ENEC25   TUV   CE ROHS   EMC

Other country in Europe: CE  ROHS EMC

Korea: KC 

Australia: SAA 

  • Are you familiar with UL standard corn bulbs?

1. Normally UL certificates from factory is UL1993 & 8750 standard. But our corn lamps get UL1993 and UL1598c certificates. They are different UL No.

Then what’s difference?

UL1993 Standard for Self-Ballasted Lamps and Lamp Adapters.

UL1598C Standard for Light-Emitting Diode (LED) Retrofit Luminaire Conversion Kits.

If led corn lamp get UL1598C, that means they already get UL1993. And UL1598c lamp can remain the original fixtures UL certificates when retrofit.

2.  UL1993 for 100% enclosed fixture or not?

You can get this information from your lamps, UL products to be required print CAUTION PART:  

Or you can get information from UL test report:


3. UL corn lamps have requirement for fixture dimension when installed? 

If UL test report showed Min.Lamp Compartment Dimensions, that means heating is limited in a space. If dimension is limited, we should think twice our corn lamps is suitable for your fixtures or not.


4. UL corn lamp suitable for dry or damp location?

UL1993 have 3 levels. Dry, damp and wet location.

Mostly IP20 corn lamps is dry location.

IP64/65 corn lamps is wet location.

  • Are you still buying DLC3.1 standard led corn bulbs?

DLC(Design lights Consortium ) published V3.1 standard in 2015.11.20. Led corn bulbs with Screw base (E39) officially joined the DLC category.

Most of the corn lamp manufacturers on the market get DLC3.1. But ours had approved DLC4.4 standard.

DLC(Design lights Consortium ) had published V4.4 standard. Compared with V3.1, V4.4 had more requirement on lumen efficiency. It required 90 lpw with fixtures, not only for the lamps.

All led corn bulbs that cannot reach DLC4.0 will be removed from DLC website start from 2017.4.1. 40% -60% of led corn bulbs would be cut from QPL!


Focus’s 100w LED Replacement for 400w Metal Halide  

Most People will ask 400w 36000lm, 100w LED 12500lm. 

12,500lm = 36,000lm? 100w = 400w?

I will explain from following reasons:


1. Low-cost operation 

Using 100w of System Energy saves over $2,860 in energy costs over the rated life of  a lamp. Versus a standard 460W Metal Halide lamp system based on $0.11 kWh.

2. The long life with 50,000 hour rated life at L70. Lasting 2.5X longer than the HID.


A simple upgrade that will work with many currently installed HID lighting systems. Uses existing fixture optics and ballast.

Instant on/ Brightness. Open fixture rated. Temperature rating for -40℃ to 60℃. Doesn’t work on reactor or electronic ballasts.

  • What is the tether kit used for?

If experiencing bad fixture sockets, arching or environmental issues this level of protection is needed.

When installing the tether kit read the instructions completely & carefully.

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