1. What are LED Lights, and do they save energy?
LED lights are much more energy efficient than all other lighting technologies that came before them. This includes metal halide, high pressure sodium, CFL, fluorescent, incandescent, and halogen lights. Any facility that replaces traditional lighting with LED will reduce its energy consumption by 50% to 80% immediately. Cost savings will also be greatly reduced due to their longer lifespan (up to 100,000 hours and more) because less time and money is spent on their maintenance.
2. How do LEDs Work?
LEDs are comprised of 3 main components: the LEDs (the light-producing chipset), the driver (used to convert AC to DC), and the heat sink (used for heat dissipation). DC power is taken by the LEDs from the driver to create light while the heat sink is used to keep the LEDs and the driver cool. Even though LEDs produce much less heat than other lighting technologies, the heat that they use must still be managed so that they can still function efficiently and realize their potential lifespans.
Efficiency is the name of the game when it comes to LED lighting, and this is why they are a superior choice to other types of lights. For example, a 400-Watt metal halide lamp can be replaced with a 100-Watt LED light.
3. Are there benefits to replacing traditional lamps with LEDs?
Yes. And there are a lot of them:
a. The cost of your electricity bill will be reduced immediately.
b. They produce less heat. Only about 5% of the electricity used by LED lights is converted into heat.
c. They have a long lifespan. 50,000 hours at a minimum and over 100,000 hours potentially.
d. They are extremely durable and practically indestructible. No brittle glass or fragile filaments are used in their construction.
e. They don’t contain any hazardous materials such as mercury.
f. They are easy to recycle. No special disposal requirements need to be considered.
4. How much money can you save when you convert to LED?
This will depend on what type of old lighting you are replacing. At a minimum, you will realize a savings of 50% when you replace fluorescent lights. This number jumps to 70% or more when replacing Metal Halide or High Pressure Sodium lights. And, as the efficiency and light quality of LEDs improve over time, the cost savings will be even greater.
5. Can you use dimmer controls with LED lights?
Yes, but there are two conditions that must be met. First, the bulb’s driver must be designed to allow it. Second, you’ll need to have the proper type of dimmer. Dimmers that are made specifically for LED bulbs can be found at most retail stores. If you use a non-dimmable LED bulb with a dimmer, it will fail, and its warranty will be voided.
Also, it’s important to know that there are two basic types of dimmers that you’ll use with LED lights: TRIAC dimming and 0-10V low voltage dimming.
TRIAC (triode for alternating current) dimming controls the flow of AC current and is typically used in residential applications. The current flow can be adjusted to set the light output of an LED bulb.
0-10V low voltage dimming is typically used with commercial and industrial LED fixtures. It requires special wiring and a special type of dimmer. Dimming is controlled by a dedicated DC voltage signal ranging from 0 to 10 volts. The light will operate at 100 percent output when the full voltage is passed (10V), 0 percent output when no voltage is passed (0V), and at any dimming percentage based on anything in between.
6. Do LED bulbs have any hazardous materials in them such as Mercury?
No. LED bulbs don’t have mercury or any other hazardous chemicals or metals. CFLs and fluorescents have a very small amount of mercury that must be disposed of correctly. So, when your LED bulb eventually stops working, you shouldn’t need to be concerned about special disposal requirements.
7. What color temperatures are available with LED bulbs?
Color temperature for light bulbs is represented as a measurement on the Kelvin scale. LED bulbs are available in a range of color temperatures, but the most common are in a range from 2700 Kelvin to 7500 Kelvin. Unfortunately, the only reliable measurement is the Kelvin scale. Lots of manufacturers use terms like Warm White, Natural White, Day White, and Cool White, but there is no standard that defines a Kelvin temperature to associate a color temperature with those terms. The warmer the light, the more yellow tones, the cooler the light, there are more blue tones.
In this example, we use terms to reflect the proper relationship to color temperatures:
2700 – 3200: Warm White – typically used in residential applications
4000 – 4500: Natural White – typically used in office applications
5000 – 5500: Day White – typically used in warehouse/industrial applications
6500 – 7500: Cool White – not typically used
8. Are LEDs used for outdoor applications?
Yes. However, they’ll need to be able to withstand outdoor conditions. This means that they’ll need to be waterproof or watertight. An LED bulb or fixture used outdoors can be damaged or rendered inoperable if water is allowed to penetrate its housing. Make sure to read its specifications to know what kind of protection it has.
Check to see what the bulb or fixture’s IP Rating is. An IP rating has two digits that tell you what level of protection it has from solids and liquids. The first digit signifies protection from solid particulates like dust (1-6) and the second digit signifies protection from moisture and liquids (1-8). An IP65 rating (or better) means that it can withstand a wet environment.
9. Will there be a decrease in light level during the course of its lifespan?
Yes. Toward the end of its operating lifespan, it will fade but at a very gradual pace which is barely noticeable. It’s called lumen degradation. It’s expressed as L70 which is the time it takes for a light to reach 70% of its initial lumen output.
10. If I want to replace a 400-Watt Metal Halide fixture, how many lumens do I need?
There are many things to consider here. The DesignLights Consortium (DLC) has denoted in their specifications that you need 10,000 lumens (at a minimum) to replace a 400-Watt Metal Halide. Some other factors come into play, like surface reflection, obstructions and other source of light, such as natural light sources coming into the building.
An indoor Metal Halide light is replaced with 15,000 to 21,000 lumens of LED.
An outdoor Metal Halide light is replaced with 12,000 to 21,000 lumens of LED.
LED Lighting Supply designs light solutions. We are product agnostics. We will select the best product that meets your needs. So, we have the ability to replace a 400-Watt Metal Halide with 10,000 lumens up to 30,000 lumens. We do find that you need more lumens indoors to do a proper replacement than you do outdoors. By using a lighting photometric analysis, we can determine how much you need to create the proper foot candles.
11. What are the steps required to replace a fluorescent tube?
There are several steps, but essentially this is no more difficult than a bulb and ballast replacement.
1. Take out the fluorescent tubes, then take out the ballast.
2. If needed, replace the existing lamp sockets in the fixture. It might be necessary to do this with single-end powered tubes if there are shunted tombstones.
3.To adapt the fixture for LED replacement tubes, you might need to rewire it. However, it’s important to note that you can also purchase ballast-compatible tubes. With these types of tubes, you can directly switch out the fluorescent tube and install the LED replacement tube without the need to rewire the fixture.
LED tubes with internal drivers use AC current, and then convert the power to DC within the internal LED driver to light the LED’s. We don’t supply tubes that can be driven from a fluorescent ballast nor do we recommend them. This is due to the fact that the fluorescent ballast will consume additional wattage which makes them less energy-efficient.
We can also provide LED tubes with external drivers. In these cases, the driver is housed outside the tube. It is typically installed in the same location as the fluorescent ballast. Like internal drivers, external drivers accept AC power and convert it to DC which is supplied to the LEDs in the tube.
If you have a native DC system (like solar lighting systems), we recommend that you use tubes with external drivers and skip the driver installation. You will have to make sure the DC power that is supplied to the fixture is compatible with the DC power requirement of the tubes.
12. When I buy LED, should I buy based on watts or lumens?
Always buy based on lumens. Watts is a number that is used to determine how much energy it takes to produce those lumens. You should also understand what is meant by lumens per watt (lm/w). This ratio tells you how much energy is used to produce light in a given bulb or fixture. For example, if you are comparing two fixtures that have the same light output (lumens), the one with the higher number of lm/w indicates that it takes less energy to produce the same light output. That’s the one you want.
13. What component of the LED system is typically the first to fail?
Almost always, it is the driver. That is why it is important to know who makes the driver in the LED fixture or retrofit that you purchase. We recommend brands like Philips, Inventronics, and Meanwell. An LED product with a 1- or 2-year warranty is an indication of how good the driver or product is. Typically, a good driver should last more than 50,000 hours.
14. What is the most common reason LEDs fail?
Heat. Heat is the enemy of electronics, the hotter it is, the shorter the lifespan of the light. With a good design, a light fixture can be made to withstand high-heat environments. A bulb or fixture that has an external driver will usually last longer than an integrated fixture that has the LEDs and driver as one unit.
15. What is Color Rendering Index (CRI)?
CRI measures the quality of light. This contrasts with lumens, which measure the quantity of light. It is a scale between 0 and 100. 0 is bad, and 100 is great. LEDs typically are in the 70-95 range. The higher the CRI, the more expensive the LED chip, and therefore the more expensive the product itself.
About the Author
Dwayne Kula is President of LED Lighting Supply. On any given day, Dwayne is writing content for the site and helps manage the marketing initiatives that are on-going. He has a Software Engineering degree and still dabbles in writing software for the company as needed. When not working, he enjoys spending time with his family, working out, playing the occasional game of golf and exploring New England.