Questions and Answers About LED Lighting – Why LED?

1. Q: What are the advantages of LED Lights?

A: LED (Light-Emitting Diode) Lights offer a multitude of advantages over traditional light sources including lower electricity consumption, much longer lifetime, higher durability, no ultraviolet and infrared radiation, low heat and smaller size.

2. Q: Can I directly replace my existing lamps with LED lamps?

A: We offer all different kinds of LED’s and some are direct replacements of incandescent, halogen and fluorescent lamps. This means, you do not have to do any changes to your existing system.

3. Q: Why should I choose LED lamps over the cheaper traditional lamps?

A: Technically, the true cost of traditional lamps are quite a bit more expensive then LED’s. Traditional lamps maybe cheaper in the initial acquisition of the lamp, however, when you consider the power traditional lamps use for a certain amount of lumens (brightness), the life cycle of a traditional lamp, then the maintenance costs maintaining the the traditional lamp, LED’s true cost is about 20-25% of traditional lamps.

– LED lights use much less energy. When installed at applications with long work hours the saved electricity cost can bring the payback time to less than 2 years.

– LED lights have much longer life, from 30,000 to 60,000 hours. Imagine that you do not have to change your lamps for the next 10 – 20 years, especially those hard to reach light fixtures.

For commercial applications long life LED Lights mean lower replacement costs and no more group re-lamping. When you start taking into consideration the reduced maintenance costs, the ROI (Return Of Investment) time for LED Lamps escalates.

LED lamps produce very little heat thus reducing the power used by your air conditioner.

LED light has no harmful UV (ultraviolet) and IR (infrared) rays.

LED lamps contain NO mercury like the fluorescent lamps. LED Lights are completely safe for the Nature and can be disposed as ordinary waste.

4. Q: Does the lifetime of a LED Light Bulb shorten by frequent on/off switches?

A: Unlike the fluorescent lamps, lifespan of LED Lamps is NOT influenced by frequent switching.

5. Q: How does a LED work?

A: The LED (Light Emitting Diode) emits light by the effect of electroluminescence. When a semiconductor diode is turned on electrons recombine with holes and energy is discharged in the form of light.
Here’s another key point, there are no moving parts to this and a big reason why life span is greatly increased. Light Emitting Diodes are often referred to as solid state lighting.

6. Q: What is the color of the light from a LED?

A: The light color of LED Lamps is measured by Correlated Color Temperature (CCT) in Kelvins. Contemporary High Power LEDs are covered with phosphor to convert light from a blue LED to a wide spectrum white light.             Most common LED Light colors used are:
         Warm White (Soft White) – 2,700 – 3,300 K – the color of the light of a traditional incandescent light bulb
         Natural White (Daylight) – around 4,000 K –
         Cool White > 5,000K – similar to moonlight, xenon lamp light color

7.  Q: What is Color Rendering Index?

A: The Color Rendering Index (CRI) is measuring the ability of a light source to simulate the colors of different objects accurately in comparison with the sunlight. Although there are critics of the subjective color rendering in practice, the CRI is widely used as a measurement of the quality of the light. Higher CRI corresponds to better quality light, in scale from 0 to 100.

8. Q: What is the CRI of LED light?

A: Generally LED lamps score above CRI 80, which is higher than many other light sources. LED Lamps with CRI above 90 are used for visual inspection tasks.

9. Q: How efficient LED lamps are?

A: The output of energy in light sources comes in the form of light or heat. The higher the ratio light to heat, the more efficient the lamp. Today’s high efficient LED lights have efficiency of about 50 %, compared to standard incandescent lamp with 2-3% and fluorescent lamps with 15-20% efficiency. Traditional lamps emit light in all directions, we call this an omni-directional lighting, LEDs however (naturally by design) only emit light in a uni-directional (single) fashion, this means that the light is easier to manage with less losses. Simply put, when trying to light up  pathway, an omni directional bulb emits light towards the sky, in efforts to fix that, we use reflectors to reflect the light that would normally go up back down. However, no matter how great the technology, we lose much of the usable light. That presents an even greater advantage in regards to LED lamps’ high efficiency over all other existing light sources.

10.Q: What is luminous efficacy?

A: The luminous efficacy is the light output per unit power input. Efficacy is measured in lumens per watt (lm/W). Nowadays commercially available LEDs have efficacy of 130 lm/W for cool white and 107 lm/W for warm white light (CREE XLamp MX-6). This is much higher when compared to incandescent bulb that produces 15 lm/W, fluorescent lamp with 60-70 lm/W and metal halides initial 90-100 lm/W.

However, the efficacy of a single LED should not be mixed with the efficacy of the lamp. Many manufacturers and resellers state the LED Lamp Light Output as sum of the output of the individual LEDs. This is not correct because there are always losses from light trapped inside the lamp. The efficacy of a LED Light Lamp, also called LED Light Engine, can be increased by better design and using high quality materials.

11. Q: Is the lumen per watt the only aspect I should consider when choosing a LED Light?

A: No, you should consider also the CRI (quality of light) and your individual visual preferences in terms of CCT (color of light). Some people like the more yellow Warm (Soft) White light that resembles the light from the incandescent lamp while others prefer the brighter and more true-color rendering Cool/Daylight white.

12. Q: What is the lifetime of a LED Lamp?

A: When properly installed and well ventilated, LED Lamps will very rarely burn. However, the brightness of the LED light fade over time, so LED Lamp’s life is measured by 2 characteristics – how much will it fade after 1,000 hours of exploitation, and when the brightness will reach 70% of the initial value.

High Quality, professional grade LED Lamps are rated at less than a decrease of 3% light output for the first 1,000 hours, and after a 30,000 – 50,000 hours for a 20% decrease in lumens.

When compared to a 400w probe start metal halide for example, which has a typical lifespan of 15,000 – 20,000 hours, but after 40% of life span (6,000 – 8,000 hours of use) there is a decrease of 35% of the initial lumens.