Encyclopedia

of Home Improvements

*Changing Light Bulbs*

Most light bulbs are very easy to change. With the light turned off simply unscrew the old bulb and screw in the new one. Be careful that the old bulb is not still hot. Bulb should be tightened snug, do not over tighten or the bulb might break when removing it next time.

Fluorescent tube bulbs are replaced by turning the old one until the prongs on the end of the tube slide down out of their receptacles on each of the fixture. The new one is inserted into the receptacles and turned a quarter turn. You will feel the prongs seat in the receptacles.

When changing a Halogen bulb you must wait for the bulb to cool down. They get very HOT! Use only a properly rated bulb; increasing the voltage and /or wattage will increase the UV output and internal pressure thus increasing the risk of rupture. To avoid damaging the glass, do not touch the bulb with your bare hands. Hold bulb with a cloth or gloves. If you do get fingerprints on the bulb clean it with alcohol before turning on power to the fixture. Make sure bulb is sitting in the socket properly and making good electrical contact.
Installing a CFL is similar to installing an incandescent bulb.

Hold the CFL by its base, rather than the tube, to prevent cracking. Do not allow the lampshade or harp to press against the glass. If a CFL should happen to break, ventilate the room and clean up the area with a disposable rag (do not vacuum). Do not touch the bulb fragments with your hands! CFLs contain a small amount of mercury, which is a required component that gives them the ability to operate. Place the contents in a closed container and properly dispose of it.

LEDs are very similar to incandescent bulbs; they fit into the same socket. They are just screwed in like the traditional incandescent bulb.

Occasionally a bulb will break while being changed. I can usually get the remaining part of the bulb out by grabbing it carefully with a pair needle nose pliers and slowly working it out.

How to install a light fixture:

Turn off light switch

Remove fixture from its location and check the wires for any fraying.

Follow instructions for new fixtures mounting hardware.

Pull supply wires and ground wires from outlet box and attach the ground wire to the ground connection on the fixture.

Connect the white wire from the box to the white wire from the fixture with a wire nut. Repeat the same procedure with the black wire. Us UL listed wire connectors suitable for the size, type, and number of conductors.

Carefully tuck all wires back into the outlet box and attach fixture as per instructions.

Check to see what size bulbs are recommended and install the bulbs.

How Light bulbs work:

The filament of an incandescent lamp is simply a resistor. If electrical power is applied, it is converted to heat in the filament. The filament's temperature rises until it gets rid of heat at the same rate that heat is being generated in the filament. Ideally, the filament gets rid of heat only by radiating it away, although a small amount of heat energy is also removed from the filament by thermal conduction.

How light bulbs burn out:

Due to the high temperature that a tungsten filament is operated at, some of the tungsten evaporates during use. Furthermore, since no light bulb is perfect, the filament does not evaporate evenly. Some spots will suffer greater evaporation and become thinner than the rest of the filament. These thin spots cause problems. Their electrical resistance is greater than that of average parts of the filament. Since the current is equal in all parts of the filament, more heat is generated where the filament is thinner. The thin parts also have less surface area to radiate heat away with. This "double whammy" causes the thin spots to have a higher temperature. Now that the thin spots are hotter, they evaporate more quickly. It becomes apparent that as soon as a part of the filament becomes significantly thinner than the rest of it, this situation compounds itself at increasing speed until a thin part of the filament either melts or becomes weak and breaks.

Why bulbs often burn out when you turn them on:

Many people wonder what goes on when you turn on a light. It is often annoying that a weak, aging light bulb will not burn out until the next time you turn it on. The answer here is with those thin spots in the filament. Since they have less mass than the less-evaporated parts of the filament, they heat up more quickly. Part of the problem is the fact that tungsten, like most metals, has less resistance when it is cool and more resistance when it is hot. This explains the current surge that light bulbs draw when they are first turned on. When the thin spots have reached the temperature that they would be running at, the thicker, heavier parts of the filament have not yet reached their final temperature. This means that the filament's resistance is still a bit low and excessive current is still flowing. This causes the thinner parts of the filament to get even hotter while the rest of the filament is still warming up. This means that the thin spots, which run too hot anyway, get even hotter when the thicker parts of the filament have not yet fully warmed up. This is why weak; aging bulbs can't survive being turned on.

Halogen Bulbs, what are halogen bulbs?

A halogen bulb is an ordinary incandescent bulb, with a few modifications. The fill gas includes traces of a halogen, often but not necessarily iodine. The purpose of this halogen is to return evaporated tungsten to the filament. As tungsten evaporates from the filament; it usually condenses on the inner surface of the bulb. The halogen is chemically reactive, and combines with this tungsten deposit on the glass to produce tungsten halides, which evaporate fairly easily. When the tungsten halide reaches the filament, the intense heat of the filament causes the halide to break down, releasing tungsten back to the filament. This process, known as the halogen cycle, extends the life of the filament somewhat. Problems with uneven filament evaporation and uneven deposition of tungsten onto the filament by the halogen cycle do occur, which limits the ability of the halogen cycle to prolong the life of the bulb. However, the halogen cycle keeps the inner surface of the bulb clean. This lets halogen bulbs stay close to full brightness as they age. In order for the halogen cycle to work, the bulb surface must be very hot, generally over 250 degrees Celsius (482 degrees Fahrenheit). The halogen may not adequately vaporize or fail to adequately react with condensed tungsten if the bulb is too cool. This means that the bulb must be small and made of either quartz or a high-strength, heat-resistant grade of glass known as "hard glass". Since the bulb is small and usually fairly strong, the bulb can be filled with gas to a higher pressure than usual. This slows down the evaporation of the filament. In addition, the small size of the bulb sometimes makes it economical to use premium fill gases such as krypton or xenon instead of the cheaper argon. The higher pressure and better fill gases can extend the life of the bulb and/or permit a higher filament temperature that results in higher efficiency. Any use of premium fill gases also results in less heat being conducted from the filament by the fill gas, meaning more energy leaves the filament by radiation, meaning a slight improvement in efficiency.

When changing a halogen bulb, turn off the power and carefully remove the bulb from the fixture. CAUTION: These bulbs operate at high temperatures and with high internal pressure and may unexpectedly shatter.

Fluorescent Lighting:

The heart of a fluorescent fixture is its ballast, an electrical transformer that steps up voltage and sends to a pair of lamp holders. Current passes through the lamp holders and excites a gas in side the fluorescent tube, causing its phosphorus -coated inner surface to glow. Because they produce far less heat fluorescent tubes last much longer and consume less power than conventional incandescent bulbs

The white powder that you see inside a fluorescent lamp is called phosphor, which is a substance that emits white, visible light whenever it absorbs light waves. Both compact fluorescent bulbs and fluorescent tubes contain a gas that gives off invisible light when excited by electricity. This invisible light travels to the phosphor coating on the bulb, where it is transformed into light visible to the human eye.

Compact Fluorescent Bulbs - CFL's:

CFL's are one of the easiest ways to save money on your electric bill. Many utilities even offer rebates just for purchasing them!

An energy star CFL uses 50% less energy and lasts up to ten times longer. They are rapidly becoming available in all shapes and sizes from candelabra to spotlights. Instead of having to change that bulb that is so hard to get to every year, now you can change it every ten years and save money at the same time!

CFLs are still more expensive than incandescent bulbs, however considering the life expectancy, and cost of operation, they are considerably cheaper in the long run. A CFL will pay for itself in about 500 hours (4 hours a day for four months). A 15-watt CFL creates the same light as a 60-watt incandescent bulb. Incandescent bulbs create heat while producing light, since CFL's don't waste energy creating heat they are much more energy efficient.

If every American replaced just 1 incandescent bulb with a CFL, enough energy would be saved to light 2.5 million homes for an entire year! Long Island will be incandescent free by 2010 - you will not be able to buy incandescent bulbs after 2010

CFL's contain mercury and should be recycled at your local hazardous waste collector.

Benefits of Energy Star Qualified CFLs:

Bulb Comparison Yearly Cost
To Operate Bulb
Comparison Yearly Cost
To Operate*
60 watt CFL $22.23 100 watt
Incandescent $37.05
14 watt CFL $5.19 23 watt CFL $8.52
Savings per
bulb, per year $17.04 Savings per
Bulb, per year $28.53

Advantages of using LEDs

LEDs produce more light per watt than do incandescent bulbs; this is useful in battery powered or energy-saving devices.

LEDs can emit light of an intended color without the use of color filters that traditional lighting methods require. This is more efficient and can lower initial costs.

The solid package of an LED can be designed to focus its light. Incandescent and fluorescent sources often require an external reflector to collect light and direct it in a usable manner.

When used in applications where dimming is required, LEDs do not change their color tint as the current passing through them is lowered, unlike incandescent lamps, which turn yellow.

LEDs are ideal for use in applications that are subject to frequent on off cycling, unlike fluorescent lamps that burn out more quickly when cycled frequently, or HID lamps that require a long time before restarting.

LEDs shock. Fluorescent and incandescent bulbs are easily broken if dropped on the ground.

LEDs can have a relatively long useful life. One report estimates 35,000 to 50,000 hours of useful life, though time to complete failure may be longer. Fluorescent tubes typically are rated at about 30,000 hours, and incandescent light bulbs at 1,000-2,000 hours

LEDs mostly fail by dimming over time, rather than the abrupt burnout of incandescent bulbs.

LEDs light up very quickly. A typical red indicator LED will achieve full brightness in microseconds; LEDs used in communications devices can have even faster response times.
LEDs can be very small and are easily populated onto printed circuit boards.

LEDs do not contain mercury while compact fluorescent lamps do.

Life Span & Energy Consumption Benefits of LED
Light Bulbs vs. Incandescent Light Bulbs Incandescent 60 watt
Light Bulb CC Vivid 2 Watt
LED Light Bulb
Life Span
How long will the light bulb last? 1000 HOURS Up to 60,000 hours
Number of bulbs used
Over 60,000 hour period 60 1
Bulb Cost
Per 60,000 hours $40.20
(60 bulbs at 67 cents each) $34.95
Electricity Usage
kWh of electricity used over 60,000 hours 3600 kWh 120 kWh
Cost of Electricity
60,000 hours at 10 cents per kWh $360.00 $12.00
Total Cost
After 60,000 hours $400.20 $46.95
Total Savings:
Money saved by installing one CC Vivid Light Bulb Save $353.25 Per Bulb!
National Energy Savings
If every household replaced just one standard 60-watt bulb with a CC Vivid LED bulb, we could save 24,184,400 watts or 24,184.4 mega (million) watts per day.

National savings information based on 103,000,000 households with an average use of 4 hrs per day per house. Based on gross watts.


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