Difference Between T5 and T8 Fluorescent Light Bulbs
T5 and T8 fluorescent tubes are often used for ambient lighting in commercial areas such as offices. T5 fluorescent light bulb is a newer technology than T8. T5 fluorescent light bulb has an efficiency of about 100 lm/W. T8 fluorescent light bulb can reach about 90 lm/W luminous efficacy.

T5 and T8 fluorescent tubes are often used for ambient lighting in commercial areas such as offices.
Since T5 and T8 fluorescent lamp dimensions are different, it is quite easy to distinguish from each other. T5 fluorescent lamp is thin and long with a diameter of 16 mm. There are two pins on each end. The distance between the pins is 5 mm. T8 fluorescent lamp is thicker than T5. The diameter of the T8 fluorescent lamp is 26 mm, the distance between the pins at both ends is 13 mm.
T5 fluorescent light bulb is a newer technology than T8. T5 fluorescent light bulb has an efficiency of about 100 lm/W. T8 fluorescent light bulb can reach about 90 lm/W luminous efficacy. In other words, T5 fluorescent lamps can use the same amount of power to produce more light.
There is no difference between the two lamp types in terms of color rendering performance, which is one of the important criteria of light quality. Both can reach 85 CRI.
T5 fluorescent tube works only with electronic ballasts. T8 fluorescent tube can work with both mechanical and electronic ballasts.
T5 fluorescent tube is 40 percent thinner than T8. Since T5 fluorescent tube is thinner, the luminaires designed for T5 fluorescent tubes are smaller than T8 luminaires. This makes them suitable for flush mounting in narrow ceilings.
T5 and T8 fluorescent light bulbs can offer up to 30,000 hours of life.
T5 fluorescent tube cannot be used directly instead of T8 fluorescent tube. The same is true for the opposite. This is because the distance between the pins and the ballasts used to operate the fluorescent light bulb are different.
T5 fluorescent light bulb offers certain advantages over T8. On the other hand, the cost of T5 fluorescent light bulb is approximately twice that of T8 fluorescent light bulb. However, it cannot be said that the same rate of performance increase was achieved between the two technologies. Therefore, it may not be a good idea to replace the currently used T8 fluorescent tubes (with fixtures) with T5.
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