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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.
Do T8 and T12 bulbs use the same ballast?
T12 and T8 lamps also differ on the ballast that they are operated with most of the time. T12 primarily run off a magnetic ballasts and T8 bulbs operate on electronic ballasts. Even though the fluorescent light socket is exactly the same for both of them, they cannot operate on the same ballast.
How do I know what type of ballast I have?
You can determine whether you have a compatible fixture in seconds. Simply turn the light on, then take a photo of the fixture using your smartphone or digital camera. If there are no dark bands on the resulting image, you have an electronic ballast that will work with direct drop-in LED tubes.
How do you read a ballast number?
The T stands for tubular and the number provides the diameter in 1/8 of an inch. Lamp diameter is determined by ballast type. Therefore, a T12 ballast must use a T12 bulb. A T5 ballast must use a T5 bulb and so forth.
Will a T8 fit in a T12 fixture?
T8 tubes are simply 1 inch in diameter versus the 1.5 inch diameter of T12 tubes. In an effort to make LED tube lights compatible with the internal dimensions of most fixtures, you will find that most LED tube lights feature a T8 or 1 inch diameter. They can indeed be used in T12 fixtures.
How do I know what size ballast I need?
By selecting a ballast with an ideal ballast factor, you can optimize the light output of your fluorescent lighting system and maximize your energy savings. To estimate your total system lumens, multiply the rated lumens of your lamp by the ballast factor. For example, 3200 lumens x 0.77 BF = 2464 total system lumens.
Are all T8 ballast the same?
Not every T8 ballast is created equal. In such a case, a programmed start ballast might be better choice. Programmed start ballasts also work well in dimming applications, because as a lamp is dimmed, the electrodes cool. Programmed-start ballasts can heat the electrodes as they cool, prolonging lamp life.
Are all T12 ballasts the same?
There are two lamp families that work with a ballast: fluorescent and HID. And there are two types of ballasts in each family: magnetic and electronic. For the fluorescent family, both T12 linear fluorescents and two-pin CFLs use magnetic ballasts. For HIDs, some metal halides and HPS lamps use magnetic ballasts.
Can I replace a T12 ballast with a T8 ballast?
The easiest and lowest price option to replace a T12 is a T8 linear fluorescent. They have become the go-to option for pre-existing T12s. If you still have magnetic ballasts, switching to a T8 will require a ballast swap.
What is T8 vs T12?
The main difference between T8 and T12 tubes is the tube’s diameter. T12 tubes are 1.5″ in diameter while T8s are just one inch. All other things—socket sizes, lengths, distance between pins—are the same. T8 LED tubes won’t fall out if you try to install them in a T12 fixture—they’ll fit just fine.
What does T8 mean on a light bulb?
A T8 lamp (on the right in the figure below) is eight-eighths of an inch, or one inch (2.54 cm), in diameter. Both T12 and T8 lamps use the medium bi-pin base, which allows T8 lamps to fit into the same luminaires as T12 lamps of the same length.
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.
How do you determine the wattage of a ballast?
A ballast factor is a number, typically between 0.70 and 1.2, that tells you how much light a lamp will emit with that ballast. So how do you get that number? Ballast factor is calculated by dividing the lumen output of a lamp-ballast combination by the lumen output of the same lamp(s) on a reference ballast.
How do I choose a replacement ballast?
It needs to fit the electrical requirements of the lamp that it will run. When purchasing a ballast, you’ll need to read the type of lamps it’s designed for, how many lamps it operates, and the voltage the lamps will run on. Choosing the right ballast for a lamp will optimize the light output and life of the bulb.
Are T8 fluorescent bulbs being discontinued?
Even some T8 lamps have been phased out. US Congress has enacted legislation to prohibit the manufacture of these and other inefficient lighting technologies, and is calling for manufacturers to meet minimum efficiency requirements and lumens per watt for new products.
