6 Common Lightbulb Questions, Answered

What makes LEDs different from CFLs? Why can’t you use certain lights outside, and just what do those numbers on the boxes mean? For today’s blog post, we’re covering every question you’ve had about the different kinds of lights - and then some!

Question: What makes LEDs different from CFLs?

Answer: The principal difference lies in the way they produce light. CFLs use a mechanism involving mercury, whereas LEDs use a semiconductor device. You can learn the difference more extensively in our previous blog post. 

Question: Okay, then what are incandescent lights? 

Answer: Incandescent lights come in all different shapes and voltages, but they all share the same mechanism. When electricity passes through the tungsten filament characteristic of incandescent lights, the bulb produces heat, therefore light. Incandescent bulbs were the most popular lights back in the day, but they have been gradually replaced with their more cost-efficient counterparts: CFL and LED lights. 

Question: What kind of incandescent lights are there? 

Answer: Incandescent bulbs encompass a wide range of different bulbs. The most common of which being GFLS, Candle, Mushroom, Classic, Reflectors, and Pygmys. 

Question: Which lights are okay to use outside? 

Answer: Here’s a good rule of thumb: incandescent and halogen bulbs are okay in covered locations, certain LEDs if they have an outdoor rating, and CFLs should NEVER be used outside. 

Question: What do the numbers on the boxes mean? 

Answer: You’re typically going to see three different letters corresponding to CRI, Lumens, and Kelvins. CRI (color rendering index) is a measure of how accurate the color looks under a white light. The higher the number, the better the lighting looks. For example, daylight has a CRI of 100. The CRI you want to look for when purchasing lights should be somewhere around 80 or higher. 

Watts used to be the industry standard way of measuring a bulb’s brightness, but now we use lumens. Typical brightness is around 800 lumens, but it can range to as high as 2,600.

Kelvins refer to the color temperature: the lower the color temperature, the warmer the bulb’s color will be. The scale for Kelvins ranges from 1,000 to 10,000. Daylight is most similar to light bulbs of 4,500K and above.

Question: I want to replace a bulb measured in watts. How do I know what kind of bulb to get in lumens? 

Answer: Here’s a simple conversion chart: 

375 lm ~ 25 W

600 lm ~ 40 W

900 lm ~ 60 W

1125 lm ~ 75 W

Question: What do the letters on a lightbulb mean? 

Answer: Those refer to the shape of the lightbulb, ranging from A-R. Type A is generally the standard light bulb you might picture in your head. Type G is more round and full. Type C resembles the shape of a candle flame. Check out a full reference with photos here.

Question: Now, how can I get electrical assistance? 

Answer: You’re in the right place! We’re proud to provide quality electrical service for the West Michigan community. Shoot us a message or call with your inquiry and we’d be happy to get started!