Q. Does it shorten the life of an LED bulb to turn it off and on?
A. No, it does not. Unlike fluorescent bulbs, LED lighting is not affected by fluctuations in electric current.
Q. Do LED light bulbs switch on instantly or do they have a delay like compact fluorescent lights (CFLs)?
A. Most LED lights switch on instantly at full brightness just like incandescent or halogen bulbs. They do not suffer from the “blooming” effect of CFL bulbs.
Q. Where are the best places to put LEDs in my home or business?
A. LEDs complement all commercial and residential settings. LEDs are ideal for settings where lighting is required for extended periods of time or hard to reach spots like high ceilings, recessed or track lighting.
Q. Can all LED lighting be dimmed or used with dimmer switches?
A. Yes, LED lighting can be used with dimmer switches. When purchasing an LED light, ensure that it is dimmable. You also need to check if it will require additional hardware to dim properly. Some LED lights require using low voltage electronic or magnetic dimmers. The dimmer switch in place may not work as well so you may need to purchase additional hardware.
Q. Why do some LED lights last longer than others?
A. Not all LED lighting is created equal. All light bulbs suffer from diminishing light over time but unlike incandescent bulbs, LEDs don’t typically fail. They lose brightness over thousands of hours. The industry considers an LED light bulb’s life span over when it reaches 70% of its initial brightness. Well-designed LED lights can last 25,000 to 50,000 hours. The actual lifespan of an LED light depends on several factors. Since heat is generated around the LED chip, an accelerated decrease in life and performance of an LED light occurs if heat is not dissipated properly. Well-designed LED lights have components to move the heat generated by the LED away from the LED chip.
Some LED manufacturers may overdrive the LED. This yields more initial brightness from the LEDs but it also results in a shorter lifespan and shifts in color temperature. Manufacturer’s who claim 100,000 + hours for their LED lights are publishing a half truth because they are typically making claims based on lab tests of the LED chip itself and not the LED light bulb or LED fixture as a whole.
Q. What about using LED lighting in fully enclosed housings?
A. LED light bulbs do not like excessive heat particularly around the LED chip and circuitry. Using LED bulbs in any tightly enclosed space will result in a high ambient temperature and reduce the ability of the bulb to dissipate heat unless some type of heat sink is built into the housing. If heat is not dissipated properly, it will diminish the life of a LED light. Most LED bulb manufacturers include warnings that their bulbs are not for use in enclosed fixtures. If you do so, you void the warranty on the product.
Q. What does Color Temperature (CT) or Correlated Color Temperature (CCT) refer to?
A. LED lighting is available in a wide range of color temperatures from the warm yellow color of an incandescent bulb to the neutral color of a halogen or a cool blue color similar to a bright but overcast day. We recommend familiarizing yourself with the color temperature scale used to define what hue of light a specific LED bulb emits. Color temperature is based on the Kelvin temperature scale, measured in degrees, and ranges from 2600°K on the low end to over 6000°K on the high end. Most home applications utilize lighting with a CCT at or below 4000°K. Most commercial environments or modern decors seeking to reproduce a daylight look use lighting with a CCT at or above 3500°K.
Q. Do LED bulbs emit UV and IR radiation?
A. Most LED bulbs emit a “cold” beam that contains only visible light. Therefore, they contain no ultraviolet (UV) or infrared (IR) light. There are several advantages to using a light that only emits electromagnetic radiation in the visible spectrum. UV or IR lights fade colors, degrade artwork and radiate thermal energy (heat) in the beam. This is why LED lighting is an ideal solution for retail shops, galleries and museums. Retailers and the art world require and demand LED lighting with excellent color rendering and no UV or IR light that can adversely affect merchandise and art displays.
Q. What does beam angle refer to?
A. Knowing the beam angle of a bulb ensures you purchase the right product or “best use” for a particular application. Light bulbs are often referred to as “spotlights” or “floodlights” which relate to beam angle. However, the term is broad and ambiguous since there exists a wide variation of beam angles for each light. For instance, one floodlight bulb may have a beam angle of 30° while another may have a beam angle of 75°. Beam angle specifically refers to the angle at which the light output has been reduced to 50% of the maximum center beam brightness. For instance, let’s say a PAR30 LED light bulb has a center beam candlepower measurement of 800. If at 30°, the one side of the beam candlepower drops to 400, you know that the beam angle is 60° (see diagram below).
It is better to utilize spotlight bulbs when you want to concentrate light to a small area or highlight a particular object. It is better to utilize floodlight bulbs when you want to achieve broad illumination such as in recessed down lighting.
Q. What is a lumen?
A. A lumen is a measurement of light output. The technical definition goes beyond the scope of our frequently asked questions but understanding lumen is becoming increasingly important as we transition from traditional light bulbs to LEDs. With incandescent lighting, most people associate brightness with wattage. A 100 watt bulb is brighter than a 75 watt bulb. However, wattage is really a measurement of power required to light the bulb and not a measurement of light output.
A 60 watt incandescent bulb produces about 800 lumens of light. LED bulbs emit the same amount of light using 12 watts or less. It is the lumens that are important. The less wattage needed to power light, the better and more efficient your lighting. In the future, lumen output will be listed on bulb packaging. It will make it easier for the consumer to compare lighting, measure efficiency and design spaces with LEDs.