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Here are answers to your LED lighting Frequently Asked Questions. We hope this page is helpful and informative. Be sure to come back from time to time as we continually add to this page to reflect the most popular questions posed by our customers.  Have another question? Contact C&G LED Lighting directly.


Q1. Do LED lights burn out?

All lights have lumen depreciation, which means the light output slowly decreases over time.  Unlike other types of lighting, LED bulbs do not burn out, but slowly decrease in brightness.  Higher quality LED products have efficient heat sinks and LED chips. Heat sinks extract heat away from the LED junction and high quality LED Chips depreciate very slowly, while cheap chips can depreciate very rapidly.

End life of LED products rate at 70% of initial luminous flux, or 70% of the original light output.  All other lights from incandescent to metal halides burn out sooner and degrade much faster than LED lights.  All other lights typically rate at when they burn out, LED lights rate and when they stop producing enough light.  LEDs are more about lumen maintenance compared to end life.  Improvements in packaging and heat sinking are improving the lumen maintenance characteristics of illumination-grade LEDs.

Q2. How do dimmable LED lights work?

The dimming design uses the most updated technology of Frequency and Peak Current Modulation, which provides even and stable dimming function ranged from 1% to 100% of full luminous flux. Pulse Width Modulation presents a technique to safely dim an LED from 1-100% of its nominal brightness. By pulsing the LED with current, and varying the duty cycle of the current waveform, the LED rapidly transitions between on and off, and the relative times spent give the impression of being dimmed.  Digital fade dimmers should be avoided.

Q3. Do LEDs attract insects?

No they do not. Insects see entirely different spectrums of light and are attracted to ultraviolet light. A side note - flowers create "nectar guides", invisible to the human eye and ultraviolet light attracts insects to flowers for reproductive purposes. This is not to say that all bugs aren't attracted to LED lights, but most can't see the light that LEDs produce.

Q4. Why does LED lighting cost more than traditional lighting?

LEDs can operate as standalone devices, but when grouped or clustered they require additional steps to operate properly. LEDs need proper components such as a circuit board, driving components and some cases and housings to endure the elements. LED circuits can be designed rapidly, but to ensure that they operate correctly and for long periods of time they require testing.


Q5. Are LED lights dimmable?

Dimmable LED bulbs from C&G are dimmable.  The dimming IC from NXP which provides even and stable dimming function ranged from 1% to 100% of full luminous flux.  Our dimmable LED products are compatible with 99% of dimmers being sold around the world, including LUTRON, OSRAM & TCL.

What this means is that our dimmable LED lighting solutions can be installed in existing homes and businesses out of the box.


Q6. Do LEDs produce heat?

LEDs produce very little amounts of heat. The heat noticed in some instances is due to on board components and other factors of the light circuit. In comparison to incandescent, LEDs produce a fraction of the heat. If LEDs are hot to the touch, they are poorly designed being overpowered due to improper circuitry.


Q7. What does CRI stand for?

The color rendering index (CRI) (sometimes called color rendition index), is a quantitative measure of the ability of a light source to reproduce the colors of various objects faithfully in comparison with an ideal or natural light source.  It makes red look red, blue look blue, etc.


Q8. How much can I save by using LED lighting solutions?

We provide a free Energy Savings Calculator download which calculates exactly how much you will save over time by switching to LED lighting solutions.  With some basic information about cost per kilowatt hour, labor costs, current lighting information and LED info you will know exactly when the ROI and total savings occur.


Q9. How do you make a white LED?

The first method is to combine light from red, green, and blue colored LEDs. If you get the right mix, the effect is white light. This is the same way your television works—a white object on the screen is really depicted using dots of red, green and blue lit up in proportions that form an impression of white. White formed this way can be “tuned” to look warm or cool by adjusting the amounts of colors in the mix.

The second method uses a blue LED with a phosphor coating. The coating emits a yellow light when the blue light from the LED shines on it. The mix of the yellow light with the blue light forms a white light. Inefficiency in the phosphor conversion is one reason that a white LED is less efficient overall than a colored LED. Some of the light energy is lost in the conversion to yellow.




Q10. What’s LED different from Incandescent and fluorescent?

LEDs differ from traditional light sources in the way they produce light.

In an incandescent lamp, a tungsten filament is heated by electric current until it glows or emits light.

In a fluorescent lamp, an electric arc excites mercury atoms, which emit ultraviolet (UV) radiation. After striking the phosphor coating on the inside of glass tubes, the UV radiation is converted and emitted as visible light。

Q11. Are LEDs affected by extreme conditions?

LEDs are geared for harsh environments and are used for both normal and extreme applications indoor and outdoor. LEDs function from -40F to 180F easily operating in environments where incandescent and fluorescent bulbs fail. There is no delay or required "warm up time" for LEDs to function.

Q12. What is an LED driver?

An LED driver is a self-contained power supply that has outputs matched to the electrical characteristics of your LED or array of LEDs.  Drivers should be current-regulated (deliver a consistent current over a range of load voltages). Dimmable LED drivers may also offer dimming by means of pulse width modulation (PWM) circuits. Drivers may have more than one channel for separate control of different LEDs or arrays.


Q13. What is the useful life of LED bulbs?

High quality, white LED bulbs last for 50,000 hours.

Useful life or active life of incandescent bulbs stands for the time it takes for half the bulbs in a carton to burn out.  Most bulbs have a useful life of 1,000 hours, but halogens last closer to 3,000 hours.

What is 50,000 hours? It is 50 times the life of a typical incandescent bulb and 5 times the lifetime of an average compact fluorescent lamp. In fact, if you ran one Green Lighting LED lamp for 6 hours per day every day, it would last for nearly 23 years. That is five presidential elections, a home remodeling or a full generation. You may never change another light bulb again.


Q14. Why do LEDs use such little power?

LEDs do not use a filament where a conductor is heated and light is created. Filament based lighting consumes more power than the light produced. LEDs produce very little amounts of heat and do not use filaments making them far more efficient in consumption and output.



Q15. Are LED diodes inherently directional?

LED diodes are not inherently directional.  One way to boost light intensity is to focus the beam more tightly.  This is accomplished not with the LED chip itself, but a lens which directs light.  MR and PAR series LEDs have a beam angle of 15 to 60 degrees.  This does not change the light output, only the direction of the light.


Q16. Why are LEDs different colors?

The color of an LED is a function of the material used to make the junction. There are two main flavors used in visible light LED junctions:

  • Indium gallium nitride (InGaN): used to make up the blue, white, true green, and UV types
  • Aluminum gallium indium phosphide (AlGaInP or AlInGaP): used to make the red, yellow, and orange types


Q17. Do LEDs have a wire filament?

No, LEDs operate using entirely different components. LEDs are diodes - they only allow power to move in one direction. The anode (+) is where the current comes in and the cathode (-) is where the current goes out, much like the positive and negative terminals of a battery. Incandescent bulbs project light in every direction (omni directional) as opposed to LED lights which project light in specified directions (such as 20, 50 and 120 degrees) due to their package design and layout.


Q18. What is an LED?

L.E.D. is the common abbreviation for a light-emitting-diode.

LEDs are based on inorganic (non-carbon based) materials. An LED is a semi-conducting device that produces light when an electrical current flows through it.

A diode is a semiconductor that permits current flow in one direction.  Semiconductor diodes are a junction of two materials, one with a positive and the other with a negative charge.  When this PN junction is applied with a forward voltage, electrons and holes are brought together releasing light energy.  Hence: Light Emitting Diode.


Q19. What’s SSL technology?

Solid-state lighting (SSL) technology uses semi-conducting materials to convert electricity into light. SSL is an umbrella term encompassing both light-emitting diodes (LEDs) and organic light emitting diodes (OLEDs).




Q20. How LED works?

An LED consists of a chip of semiconducting material treated to create a structure called a p-n (positive-negative) junction. When connected to a power source, current flows from the p-side or anode to the n-side, or cathode, but not in the reverse direction. Charge-carriers (electrons and electron holes) flow into the junction from electrodes. When an electron meets a hole, it falls into a lower energy level, and releases energy in the form of a photon (light).

Q21. When LED was invented?

LEDs were first developed in the 1960s but were used only in indicator applications until recently.
The electronics industry has used LED technology for several decades as indicator lights for various electronic devices. In more recent years, LED technology has progressed to the point where it is viable for general lighting applications.

Q22. Why LED's?

As a rule, LED bulbs use 90% less electricity than standard bulbs. They have an unparalleled even spectrum of light and have a lifespan beyond ten years. LED's provide us the most efficient way to save energy and conserve our natural resources. If LED's were implemented right now universally, we would not need to build another power plant. LEDs would actually eliminate the need for over 30 existing power plants!

Q23. How LED emit different color?

The specific wavelength or color emitted by the LED depends on the materials used to make the diode. Red LEDs are based on aluminum gallium arsenide (AlGaAs). Blue LEDs are made from indium gallium nitride (InGaN) and green from aluminum gallium phosphide (AlGaP). "White" light is created by combining the light from red, green, and blue (RGB) LEDs or by coating a blue LED with yellow phosphor. See "Color Quality" section for more information.


Q24. What’s Low Power LEDs?

Low power LEDs commonly come in 5 mm size, although they are also available in 3 mm and 8 mm sizes. These are fractional wattage devices, typically 0.1 watt, operate at low current (~20 milliamps) and low voltage (3.2 volts DC), and produce a small amount of light, perhaps 2 to 4 lumens.

Q25. What’s High Power LEDs?

High power LEDs come in 1-3 watt packages. They are driven at much higher current, typically 350, 700, or 1000 mA, and—with current technology—can produce 40-80 lumens per 1-watt package.


Q26. Why have past attempts to create general illumination LEDs failed?

Conventional approaches to developing general illumination LEDs often involved retrofitting existing fixtures to house the new LED technology.

Instead of investigating the benefits and challenges of LEDs, many early attempts simply used traditional lighting standards and housings.

The problem was that LED technology breaks all traditional rules, and it quickly became apparent that old thinking couldn't be applied to this new technology.

Q27. Why don't LEDs function as efficiently in a traditional fixture housing?

An LED module may physically fit into an existing housing, but that housing doesn't leverage the inherent qualities of the LEDs. Standard housings can't handle the challenges of LED thermal management, which is vastly

different than thermal management for traditional incandescent or fluorescent lighting. Also, the optical design used in most traditional fixtures doesn't maximize the LED's efficiency.


Q28. Do I have to replace LED diodes?

An LED does not burn out like a standard lamp, so individual diodes do not need to be replaced. Instead, the diodes gradually produce lower output levels over a very long period of time. If one LED fails, it does not produce a complete fixture outage.