Since their introduction as a commercial product in 1939, many different types of fluorescent lamp have been introduced. Are you a contractor? Image courtesy of RetrofitCompanies.com. Original 4–13 W range from 1950s or earlier. T12 primarily run off a magnetic ballasts and T8 bulbs operate on electronic ballasts. Soft White. The other common lamps are the larger T8 (eight eighths inch = 1") and T12 (twelve eights inch = 1½" tubes). It's not made electrically for that type of ballast, the T8 light bulb is. It was simply making the cheapest lamps possible for a marketplace that was exploding with the possibilities of fluorescent lighting. These are the basic different characteristics of each different fluorescent lamp type that is most commonly used in offices and … If you try to put a T12 lamp in an electronic ballast, it will generally flicker a lot and have some problems even though it may light up. However, follow-on retrofit replacements for all the other original T12 tubes were T8, which helped with creating the required electrical characteristics and saving on the then new (and more expensive) polyphosphor/triphosphor coatings, and these were even more efficient. It was largely driven by that and when other people start to see that it would work great for an office situation, improving productivity then it was also adopted there. Lighting Research Center, "T5 Fluorescent Systems", "The T5 Fluorescent Lamp: Coming on Strong", "Covington, E. J. Sometimes, they even produce more light than T12s. That is not true of fluorescent lamps, because the lamp must match theballast in the fixture. Systematic nomenclature identifies mass-market lamps as to overall shape, power rating, length, color, and other electrical and illuminating characteristics. 5 x BRITE SOURCE T12 Fluorescent Tubes - 2ft 4ft 5ft 6ft 8ft - 20w 40w 65w 75w 100w (2ft - 20w [3500k - Standard White - 535])) Brand New 4.7 out of 5 stars 6 £14.99 £ 14 . While both bulbs come in standard lengths, commonly 4 feet, the designation of 8 or 12 refers to the difference in the diameter of the bulb. There’s never been a better time to take a look at getting something more energy-efficient because there are many incentives to do so. Cool White. Notice: It can be works with T12 fixture if bulb base is G13 Bi-Pin. T4. Around 1980 (in the UK, at least), some new fluorescent fittings were designed to take only the newer, retrofit tubes (the lamp holders are designed not to take T12 tubes, except for 8 ft length). Color is usually indicated by WW for warm white, EW for enhanced (neutral) white, CW for cool white (the most common), and DW for the bluish daylight white. Another improvement that came along with T8 bulbs was an improved color rendition as well. T8 bulbs use about 35% less electricity to produce the same amount of light as a T12. Take a look at all the different types of LED light fixtures on our website that utilize this type of T8 configuration and you’ll probably find something that will work great for you. 81. Cover: Clear / Milky. Coverage of the reflector ranges from 120° to 310° of the lamp's circumference. Philips 17-Watt 2 ft. It took a very long time but finally back in the mid-80s, T8 lamp technology was introduced and became the new standard for energy efficiency and people began moving to that type of lighting. T8 tubes are simply 1 inch in diameter versus the 1.5 inch diameter of T12 tubes. The partial pressure of the mercury vapor alone is about 0.8 Pa (8 millionths of atmospheric pressure), in a T12 40-watt lamp. Lamps are typically identified by a code such as FxxTy, where F is for fluorescent, the first number (xx) indicates either the power in watts or length in inches, the T indicates that the shape of the bulb is tubular, and the last number (y) is the diameter in eighths of an inch (sometimes in millimeters, rounded-up to the nearest millimeter). Other common sizes are T12 bulbs which are twelve eighths of an inch or 1.5 inches diameter, and the T5 lamps which are five eighths of an inch, or .625 inches in diameter. If a T12 and a T8 use the same bi-pin base, you can use them interchangeably with the same lighting fixture as long as you double check the milliamp (mA) requirements of the ballast. 99 ($16.67/Count) $124.83 $124.83 A typical second generation T8 bulb produces about 80 lumens per Watt. The difference between the T8 and T12 is simply that the T12 has a slightly larger tube diameter. You will usually … That number is divided into 8 to translate into inches. On tri-phosphor and multi-phosphor tubes, the first digit indicates the color rendering index (CRI) of the lamp. for pricing and availability. Fluorescent bulb widths are measured in eighths of an inch. So it's more than just energy efficiency, it's also the effect that it has. The good news is that the sockets that are being used today in T8 light fixtures, can be used for the LED T8’s that are coming out on the market all the time. On the most basic level, the T12 and the T8 bulbs have a different diameter tube thickness. Also from the 1930s, not as efficient as new lamps. T8. for pricing and availability. Aperture lamps were commonly used in photocopiers in the 1960s and 1970s where a bank of fixed tubes was arranged to light up the image to be copied, but are rarely found nowadays. These lamps are recognizable by their large diameter (21/8"), grooved tube shape and an R17d cap on each end. Fluorescent … Also, let us know if we can help you determine what might be the best way to go for more efficient lighting. they were designed for, these are based on multiples of the 300 mm (11.8 in) "metric foot" instead of the 12 in (305 mm) imperial foot, but are all 37 mm (1.5 in) shorter to allow space for the lampholder connections within the 300mm modular units, and for much easier insertion into and removal from troffer lights within the grid. This light specifically is a T8 size. Fluorescent tube shape. Note that because these tubes were all designed as retrofit tubes to be fitted in T12 fittings running on series ballasts on 220–240 V supplies, they could not be used in 120 V mains countries with inherently different control gear designs. Fluorescent tubes are measured in eighths of an inch, with the measurement being drawn from pin to pin at the end of the tube. Very high output (VHO) lamps with reflectors may be coded as VHOR. All of these lamps use the same technology as linear fluorescent tubes but are wrapped into shapes which make them more suitable for smaller spaces. I hope that answers your question, let us know if there's anything else we can help you with. ... Click to add item "Sylvania® 40W U-Bend Cool White T12 Fluorescent Light Bulb" to … Model #10244. For instance, the more popular and often the best, T8 LED lamps have a one-inch diameter (1/8). The last two digits indicate the color temperature of the lamp in kelvins (K). Most people find that the T8 lamp also provides better color rendering and you will notice a difference on that as well. Designed to run on the existing 125 W (240 V) series ballast but with a different gas fill and operating voltage, the tube operated at only 100 W. Increased efficiency meant that the tube produced only 9% lumen reduction for a 20% power reduction. This “T” stands for tube and the number that follows is the diameter of the tube. Now with the advent of LED T8 bulbs, people can now move into something that’s even more energy-efficient and won’t have to have a ballast anymore if they don’t want it. ... (T8) 4100 K Cool White Fluorescent Light Bulb (36-Pack) Item #1484826. The T5 diameter is nearly 40% smaller than T8 lamps and almost 60% smaller than T12 lamps. For example, if the last two digits on a lamp say 41, that lamp's color temperature will be 4100 K, which is a common tri-phosphor cool white fluorescent lamp. 99 ($16.67/Count) $124.83 $124.83 [7] Conversely, a T12 tube on a T8 ballast will usually draw too much power and so may burn out the ballast, unless it is within the range that the particular model of electronic ballast can compensate for. As we describe in our how to article, T8 and T12 feature the same G13 bi-pin connector. Production of the largest size T12 (38mm) has ceased. The most common that we see is a fluorescent bent T8 with six-inch leg spacing. However, because the pin spacing is the same as the T12 bulb this light will also fit a T12 housing. So a T8 has a one inch diameter. T4 PL. The most common form of fluorescent lamp is a straight tube. The smaller the lamps the more energy efficient they are. T4 = 4/8" bulb diameter or 1/2" T5 = 5/8" bulb diameter T8 = 8/8" bulb diameter or 1" T12 = 12/8" bulb diameter or 1 1/2" Within a given bulb size in diameter or thype, the … If no markings are available, the size in diameter of the tube is the easiest way to determine the type you have installed. It was that economic consideration that sometimes retarded the move to more efficient T8 lamps. Fluorescent bent lamps come in a few different options. U-shaped tubes are FB##T##, with the B meaning "bent". The tube type should always match the markings on the light fixture. Since about the early to mid-1950s to today, General Electric developed and improved the Power Groove lamp with the label F##PG17. T9 + See All. T5 bulbs use about 45% less energy than T12s. GE Blacklight 20-Watt 24-in Medium Bi-Pin (T12) Black Fluorescent Light Bulb. The sizes of fluorescent tubing range from T2 to T17. No such designation exists for the amount of reflector coverage the lamp has. A T8 has a one inch (8/8 inch) diameter, a T5 has a 5/8 inch diameter, and a T12 is a 12/8 inch (1.5 inch) in diameter. It was discovered many years ago that if you could bring the tube to a narrower diameter, efficiencies of the light bulb itself would be increased. Another example is color matched aperture lights (with about 30° of opening) used in the food industry for robotic quality control inspection of cooked goods. Some lamps have an internal opaque reflector. Aperture lamps have a clear break in the phosphor coating, typically of 30°, to concentrate light in one direction and provide higher brightness in the beam than can be achieved by uniform phosphor coatings. High-output lamps are brighter and are driven at a higher electric current, have different ends on the pins so they cannot be used in the wrong fixture, and are labeled F##T##HO, or F##T##VHO for very high output. T8 lamps are smaller than T12 lamps. Typical diameters are T12 or T38 (1.mw-parser-output .sr-only{border:0;clip:rect(0,0,0,0);height:1px;margin:-1px;overflow:hidden;padding:0;position:absolute;width:1px;white-space:nowrap} 1⁄2 inch or 38 mm) for residential lamps with magnetic ballasts, T8 or T26 (1 inch or 25 mm) for commercial energy-saving lamps with electronic ballasts, and T5 or T16 (5⁄8 inch or 16 mm) for very small lamps, which may even operate from a battery-powered device. Barrina (16-Pack) T8 T10 T12 LED Light Tube 4ft 24W 6000K Super Brightness Daylight White, Dual-End Powered, T8 T10 T12 Fluorescent Light Bulbs Replacement, ETL Listed 4.4 out of 5 stars 571 $99.99 $ 99 . The other thing that’s changed is that color temperatures became more precise over time. Find fluorescent light bulbs at Lowe's today. Large size for F90T17 (preheat) and F40T17/IS (instant start), Per T2—T12, T17 the number indicates the tube diameter in , This page was last edited on 22 December 2020, at 20:06. That's not always the case as sometimes people changed their T12 ballast to be electronic years ago. 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. T12. In the 1990s,[citation needed] various energy-saving tubes were introduced in North America, but unlike the T8 tubes introduced in Europe, the T8s are not retrofits and require new matching ballasts to drive them, while some T12s can use the older ballasts. Now we're explaining what T8 means. Power ratings and lengths not standardized (and not the same) between different manufacturers. 99 Even though the fluorescent light socket is exactly the same for both of them, they cannot operate on the same ballast. 75-Watt 96-in Single Pin (T12) 6500 K Daylight Fluorescent Light Bulb (2-Pack) Item #903838. Lamps are typically identified by a code such as FxxTy, where F is for fluorescent, the first number (xx) indicates either the power in watts or length in inches, the T indicates that the shape of the bulb is tubular, and the last number (y) is the diameter in eighths of an inch (sometimes in millimeters, rounded-up to the nearest millimeter). Other non-standard designations apply for plant lights or grow lights. This does not affect their light output as it’s the same as that of T12s. T5. For some applications, one T5 bulb can replace two T12 bulbs, providing even greater energy savings (a process called “de-lamping.”) Running a T8 tube with a ballast for T12 will reduce lamp life and can increase energy consumption. It's engineered differently to operate best on electronic ballasts of various types whether it be an instant start or a program start. This will reveal a lot about your current fluorescent tube and usually indicate if the bulb is T8 or T12. Bright White. The results are in: the operating cost of an LED 50% less than that of a T12. LED tube lights work in the same sockets as the T8 and possibly the T12 depending on what you have, making them an obvious retrofit opportunity with a fast payback. Home Cart Login FAQ Contact / About Email Us Returns Privacy. 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