T9 Circular fluorescent lamp, also known as circular lamp or ceiling lamp bulb, uses bent circular glass tube (usually T9) to achieve a round lighting area. Due to the requirement of higher power lamp to replace light bulb to cover larger area, circular fluorescent lamp is invented for the purpose. It is widely used in home ceiling light, or outdoor wall mounting damp proof fixture. Similar to straight fluorescent tube, it uses halogen or tri-phosphor powder coated glass tube of diameter Ф29mm, which power rating ranges from 22w, 30w, 32w and 40w. T9 circular lamp uses 4-pins base depending on sizes of the lamp, which is GR10Q (4-pins) base. T9 circular lamp mainly work with electronic ballast in the market. They use solid state mercury (amalgam), which make it more safe, stable and environmentally friendly product.

Fluorescent lamp is light on base on low-pressure mercury vapor discharge mechanism, which it is mandatory to work with an external device, which is usually electronic ballast. When power is connected, high temperature is created at the inner filament at both end of the tube. The high temperature vaporize mercury inside the tube to form a complete circuit inside the tube, which ionized mercury will hit on phosphorus power to create a visible spectrum.

Fluorescent lamp is a good replacement product of incandescent lamp. The first advantage of fluorescent lamp towards incandescent is the tubular shape of fluorescent lamp, which allows large area lighting with more diffused and even lighting distribution or reduced glare. Besides, it has higher efficiency of 50-100lm/w, which is 5-15lm/w higher than incandescent lamp. Fluorescent lamp also produces less heat which is about one-fifth the heat of equivalent incandescent lamps. This greatly reduces the size, cost, and energy consumption devoted to air conditioning for office buildings that would typically have many lights and few windows.

The body of fluorescent lamp is made of powder coated glass fitted with aluminum end caps. For powder, there are 2 options, halogen powder and tri- phosphor. Fluorescent tube has 2 choice of powder coating. If you prefer a higher color rendering (CRI), tri-phosphor powder could be used for Ra80. If more economical model is preferred, halo phosphor of RA70 could be used. Both powders allow CCT customization ranging from 2700 – 6500K, which extra high CCT up to 8000-12000K is also possible. For decorative purpose or aqua plant purpose, we also have suitable powder which create color lights (Red, Green, Blue, Yellow) or plant growing spectrum. Compare with halogen power, tri-phosphor is higher quality, longer lifetime, higher efficiency and CRI. Halogen efficacy is usually 60-70lm/W, while tri-phosphor can make more than 80lm/W. Fluorescent lamp can reach 360° beam angle, the light is soft and not dazzle, more comfortable light than incandescent lamp and led lamps.

Fluorescent lamp work in the present of a ballast, which could be a magnetic ballast or an electronic ballast. Typically, T4, T5, T6 fluorescent lamp use electronic ballast (unless the tube power is low, magnetic ballast could be use). While T8, T10 and T12 fluorescent lamp can work with both electronic ballast and magnetic ballast. Magnetic ballast needs to be used together with a start to trigger initiation high voltage for the tube the light on. A fluorescent lamp on average, last 10 to 20 times longer to equivalent incandescent lamp when operated several hours a day. Standard lifetime of fluorescent lamps is 8,000 to 12,000 hours.

Fluorescent lamp has a wide range of applications. For example, they could be use in office or resident building in appropriate ceiling lamp fixture using electronic ballast. They could also be used with in small sizes shops to enhance appearance of merchandizes. They could also be use in wide range of projects including hotels, restaurants, schools, hospitals which are usually in appropriate lamp fixture. In outdoor walls, damp proof fixture (also called bulk head) fitted with circular fluorescent lamps are common outdoor lighting.