ELECTRIC LAMPS - PART – 03 – OPERATION OF COMPACT FLUORESCENT LAMPS (CFL)

INVENTOR OF COMPACT FLUORESCENT LAMP

Ed Hammer, a retired General Electric engineer invented compact fluorescent while working at the company in 1970s.

He was born on December 27, 1931.

He received his bachelor’s degree from Manhattan college in1954.

He was an engineer at the forefront of fluorescent lighting research.

His technological contributions in incandescent, fluorescent and High Intensity Discharge (HID) light sources earned him over 35 patents.

He has published more than 40 papers and was awarded the Edison Medal by the Institute for Electrical and Electronics Engineers in 2002.

He lived for 80 years in the planet and even today he lives in the form CFL and he died on July 16, 2012.

COMPACT FLURESCENT LAMPS

A traditional 75 watt incandescent light bulb produces 1170 lumens of light and lasts on average 750 hours. But a CFL produces the 1170 lumens uses only 20-21 watts.

The CFL uses only 1/4 to 1/3 the amount of energy to produce the same light as an incandescent light bulb.

1. A compact fluorescent lamp (CFL), also known as energy

    saving light.

2. Like all fluorescent lamps, CFLs contain mercury, which

    complicates their disposal.

3. CFLs radiate a different light spectrum compared to

    incandescent lamps.

4. New phosphor compositions have improved the colour of the

    light emitted by CFLs in such a way that the best warm white

    CFLs are nearly similar in colour to standard incandescent

    lamps.  

CFL COLOURS

• Red, green, orange, blue, and pink, primarily for novelty

   purposes.

• Blue for phototherapy.

• Yellow, for outdoor lighting, because it does not attract

   Insects.

• Black light (UV light) for special effects.

MAIN PARTS OF CFL

There are two main parts in a CFL:

(I) the gas‐filled tube and (II) the magnetic or electronic ballast.

1. An electrical current from the ballast flows through the gas

    (mercury vapour), causing it to emit ultraviolet light.

2. The ultraviolet light then excites a phosphor coating on the

    inside of the tube.

3. This coating emits visible light.

4. Standard CFLs do not respond well in dimming applications

    and special lamps are needed when dimming is required.  

5. CFLs with electronic ballasts are more common.

A SPIRAL‐TYPE INTEGRATED COMPACT FLUORESCENT LAMP, with combined tube and electronic ballast. This style has slightly reduced efficiency compared to tubular fluorescent lamps, due to the excessively thick layer of phosphor on the lower side of the twist. Despite this, it has become one of the most popular types among consumers since its introduction in the mid 1990’s.

WORKING OF CFL

1. When a voltage is applied across the electrodes, the gas

    inside the tube gets ionized, conducts electricity and in the

    process generates ultraviolet (UV) light.

2. When the UV light hits the phosphor coating on the inside of

    the tube, the material glows to produce visible light.

3. When the lamp is switched on, a component called the

    ballast produces a high voltage between the electrodes,

    which is necessary for the initial ionization of the gas in the

    tube.

4. Once the lamp starts operating, the current and light output

    can be maintained using a much lower voltage.

5. Unlike incandescent lamps, the little heat produced in a

    Fluorescent lamp is just a byproduct and most of the energy

    is converted into light.

6. Due to their much better efficiency in converting electricity

    to light, which is about 40 to 50%, a CFL that produces the

    same amount of light as an incandescent lamp consumes

    two-thirds less power and produces very less heat in

    comparison.

TYPES OF CFL

1. SPIRALS - It is the most popular type of CFL. Spiral CFLs

    create the same amount of light as traditional incandescent

    bulbs, but use less energy.

2. A-SHAPED – A-shaped bulbs combine the efficiency of the

    spiral bulbs, with the look and feel of the traditional

    incandescent lamp.

3. GLOBE – Globe-shaped bulbs are ideal for bathroom vanity

    bars and ceiling pendants.    

4. TUBED – Basically straight versions of the spiral bulbs, tubed

     bulbs work well in lamps that have slender covers such as

     wall brackets.

5. CANDLE – This types are ideal for use in decorative fixtures.

6. POSTS - Covered post bulbs are great for outdoor fixtures;

    manufacturers design these bulbs to hold up to outdoor

    conditions. There are also yellow "bug light" covered posts,

    designed to keep away insects.

7. Indoor Reflectors – Reflector bulbs are perfect for providing

    directional light and suitable for ceiling lights in kitchens.

8. Outdoor Reflectors – These reflector bulbs are sealed to

    withstand the rain and snow. They are usually much larger

    than the reflectors designed for use inside.

ADVANTAGES OF CFL

1. The biggest advantage of a Compact Fluorescent Lamp (CFL)

    is its low energy consumption.

2. It also produces less heat, with a much higher life than

    Incandescent or halogen lamps and produces pleasant light.

3. Fluorescent lamps and CFLs are very similar.

4. In fact, a CFL is just a compact version of a fluorescent lamp

    that is smaller and easier to install.

5. The glass tube is bent and both its ends are fixed onto a base

    that holds the ballast and can fit into standard incandescent

    bulb sockets.