# What is the difference between t8 and t12 fluorescent lights?

The number that comes with the T is used to denote the diameter of the fluorescent tube. Since the measurements come in eights of an inch, the T8 has an inch of diameter while a T12 comes in 1.5 inches. The narrower your choice of a fluorescent lamp is, the more efficient its energy output will be.

T12 tubes pull 40 watts, and are frequently being replaced with lower wattage t8 tubes, which operate on 32 watts. When posing the question can a t8 light work on a t12 ballast, the short answer is no. The only way around the dilemma is to replace the ballast.

Secondly, what is the difference between t8 t10 and t12 fluorescent tubes? The main difference is in sizeā¦the T8 is one inch in diameter and everything else is divisible by that number: T5 = 5/8 inch, T6 = 6/8 inch, T8 = 1 inch, T10 = 1.25 inches (10/8), T12 = 1.5 inches in diameter (12/8). While the size is the main difference there are other differences that are worth mentioning.

Similarly, how do I know if I have a t8 or t12 ballast?

This will reveal a lot about your current fluorescent tube and usually indicate if the bulb is T8 or T12. If no markings are available, the size in diameter of the tube is the easiest way to determine the type you have installed. T8 tubes are 1-inch in diameter and T12 tubes are 1 1/2 -inch.

Are t8 and t12 sockets the same?

T12 primarily run off a magnetic ballasts and T8 bulbs operate on electronic ballasts. But most people have them operating on a magnetic ballast. Even though the fluorescent light socket is exactly the same for both of them, they cannot operate on the same ballast.

### Do I need to remove the ballast to use an LED bulb?

LED technology does not require a ballast to regulate the amount of energy flowing to the lights. Additionally, removing the ballast will reduce energy usage and result in even great cost-savings as ballasts continue to draw more power than necessary.

### Do I need to change the ballast for LED lights?

No LED bulbs require a ballast, although some are engineered to work with an existing ballast. You will find ballast-compatible, or “plug-and-play” LEDs that are designed to replace linear fluorescents, compact fluorescents, or HIDs. Incandescent and halogen lamps do not require a ballast.

### Are t12 bulbs being discontinued?

In effect since July 2012, the legislation eliminates nearly all 4-foot T12 lamps, some 4-foot T8 lamps, most 8-foot T12 lamps, and almost all standard halogen PAR38, PAR30 and PAR20 lamps from the market. T12 technology is over 80 years old. Since that time, lamps and bulbs have been developed that just work better.

### Can I put LED bulbs in my fluorescent fixtures?

Many LED tubes are “plug and play”, meaning you can just install them like you would a fluorescent bulb. For this to be true, look for bulbs that are “ballast-compatible” meaning that they can use the ballast already installed in your fluorescent fixture to power the LEDs.

### What happens if you use wrong ballast?

If you use a wrong sized ballast the LRC will not be tuned so you are likely to not start the lamp at all. There is the possibility of burning out components pre-maturely also due to overcurrent and overvoltage conditions particularly if using a larger ballast on a smaller fixture.

### Can you replace t12 fluorescent tubes with LED?

Install a direct wire or ballast-bypass linear LED lamp. Right now, a ballast-bypass is our top LED replacement option for T12 fluorescent tubes. Ballast-bypass LEDs work straight off the line voltage flowing directly to the sockets, requiring you to remove the original fluorescent ballast.