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Presentation on the topic of mercury-containing lamps. Advantages and disadvantages of fluorescent lamps

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Energy-saving lamps. The work was completed by: student of class 11 “B” of Municipal Educational Institution “Secondary School No. 1”, Izobilny Maria Germanova Teacher: Vasina Irina Vasilievna

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Every year, humanity's needs for electricity are increasing more and more. As a result of analyzing the prospects for the development of lighting technologies, experts recognized the replacement of outdated incandescent lamps with energy-saving lamps as the most progressive direction. Experts believe that the reason for this is the significant superiority of the latest generation of energy-saving lamps over “hot” lamps.

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Goal of the work. 1. Find out whether compact fluorescent lamps are today an alternative for lighting your homes as highly efficient, energy-saving lamps. 2. Calculate the energy costs of a typical residential building.

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Gas-discharge lamps, unlike incandescent lamps, emit light due to an electrical discharge passing through the gas filling the space of the lamp: the ultraviolet glow of the gas discharge is converted into light visible to us.

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Why an energy-saving lamp? Light output. Life time. Low heat dissipation. Light distribution. Possibility to choose lighting color. high cost warm-up time limited temperature range strict voltage requirements harmful to people with excessive skin sensitivity ADVANTAGES DISADVANTAGES

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Simply replacing conventional light sources with their energy-saving relatives will reduce energy costs by 4 times

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Energy-saving lamps can have different color temperatures Y - 2700 K - warm (yellow) light; N - 4000 K – neutral (daylight) light; W - 6400 K – cold (white) light.

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Watch the temperature! IF you choose energy-saving lamps for your apartment, remember - you should pay attention to the light temperature and color spectrum. Energy-saving light bulbs often seem uncomfortable to the eye only because they are incorrectly selected for the room. In addition, a lamp that is too bright for a given footage will be harmful to the eyes in the same way as one that is too dim.”

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Possibility of choosing the color of the glow 3. Cold white light (6000-6500 K) - bright white, bluish lighting. Suitable for office premises, offices. But in the kitchen and nursery it will cause obvious discomfort, tiring the eye. 2. Warm white light (4000-5000 K) - a tone closest to the standard “Ilyich light bulb”, neutral soft light. Suitable for living room and children's room. 1. Warm light (2700-4000 K) - yellowish, the warmest color in the spectrum. Suitable for kitchen and bedroom. But in the work area it will cause irritation and discomfort.

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Calculation of energy savings and monetary costs when using energy-saving lamps.

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Questioning. Questions: 1. How many lamps are there in your apartment? 2. How many of them are energy efficient? 3. Do you know the “+” and “-” of energy-saving lamps?

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According to Greenpeace, if every Muscovite replaces one 100 W incandescent lamp with a 23 W energy-saving lamp, the total electricity savings in Moscow will be about 800 MW. And this is more than half of the existing electricity shortage in the capital. According to Greenpeace, if a person works for a year (240 days, 8 hours a day) in an office under artificial lighting with fluorescent lamps with a very high illumination level of 1000 Lux (5 times the optimal illumination level for housing), then this is equivalent to staying outdoors in Davos (Switzerland) in the summer for one hour at noon every day for a total of 12 days. Interesting Facts.

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Important! Recently, the World Health Organization, citing the Canadian and British ministries of health, stated that such popular energy-saving lamps are not at all safe: they contain highly toxic mercury, and background radiation and electromagnetic radiation are equal to those produced by ultraviolet light. In Europe, for example, spent energy-saving lamps are collected in special containers for... toxic waste. But here, manufacturers do not even consider it their duty to inform the buyer about such a need.

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From the point of view of saving electricity and money, energy-saving lamps are more preferable. However, the psychological factor of “familiarity” and a cautious attitude towards everything new prevents you from completely switching to a new type of lamp. It is necessary to find a “golden mean”: - a gradual transition to a new type of lamps - taking into account the “-” energy-saving lamps, use incandescent lamps in parallel with them CONCLUSION

A fluorescent lamp is a gas-discharge light source in which an electric discharge in mercury vapor creates ultraviolet radiation, which is converted into visible light using a phosphor mixture of phosphorus and other elements. The luminous output of a fluorescent lamp is several times greater than that of incandescent lamps of similar power. Fluorescent lamps can last up to 10 times longer than incandescent lamps, provided the power supply, ballast, and switching limits are met.

The most common are high- and low-pressure gas-discharge mercury lamps. high-pressure lamps are used mainly in street lighting and in high-power lighting installations; Low pressure lamps are used for lighting residential and industrial premises. A low-pressure gas-discharge mercury lamp (GRLND) is a glass tube with a phosphor layer applied to the inner surface, filled with argon under a pressure of 400 Pa and mercury (or amalgam). Plasma displays are also a type of fluorescent lamp.

The popularity of fluorescent lamps is due to their advantages (over incandescent lamps): significantly greater light output (a 20 W fluorescent lamp provides the same illumination as a 100 W incandescent lamp) and higher efficiency; lamp emission spectrum close to natural; variety of shades of light; diffused light; long service life (hours, as opposed to 1000 for incandescent lamps), provided that sufficient quality of power supply, ballast is ensured and restrictions on the number of switches on and off are observed (therefore, they are not recommended for use in public areas with automatic switches with motion sensors). The disadvantages include: chemical hazard (LL contain mercury in amounts from 10 mg to 1 g); uneven, line spectrum, unpleasant to the eye and causing color distortions of illuminated objects; degradation of the phosphor over time leads to a change in the spectrum, a decrease in light output and, as a consequence, a decrease in LL efficiency; flickering of a lamp with double the frequency of the supply network the presence of an additional device for starting the ballast lamp very low power factor of the lamps such lamps are an unsuccessful load for the electrical network

LED lamps or LED lamps use LEDs as a light source and are used for household, industrial and street lighting. The LED lamp is one of the most environmentally friendly light sources. The LED lighting principle allows the use of safe components in the production and operation of the lamp itself. LED lamps do not contain mercury-containing substances, so they do not pose a danger in the event of failure or destruction. There are complete devices, lamps, and elements for lamps, replacement lamps. LED lamp is an independent device. The lamp body is most often unique, specially designed for an LED lighting source. Structurally, such a lamp consists of a housing, an LED light source and an electronic driver (power converter).

All types of lamps can be divided into three groups: 1. LED lamps for streets, parks, roads, for architectural lighting. They are carried out in a housing protected from moisture and dust; in addition, the housing usually acts as a heat sink and is made of materials that conduct heat well. 2. Lamps for industrial purposes, housing and communal services and offices. Such lamps are often produced in a vandal-proof design, equipped with a special screwdriver and special screws that protect the housing from unauthorized opening. The diffuser of modern anti-vandal lamps for housing and communal services is made of polycarbonate material, which is tens of times stronger than traditional glass. 3. Lamps for household needs are usually produced with low power, but must satisfy numerous requirements for lighting quality, electrical safety, fire hazard and, to a large extent, appearance. Often household lamps have replaceable lamps.

The advantage of an LED lamp is low energy consumption, long service life from 30,000 to 50,000 hours or more, ease of installation, lower body temperature compared to an incandescent lamp with comparable brightness, high mechanical strength, and often small dimensions. LED lamps are well suited for lighting museums and rarities, since the lamp spectrum does not contain an ultraviolet component. The main disadvantage is the high price. In addition, if any of the elements fails, the lamp most often must be replaced with a similar one. These shortcomings are most often compensated by energy savings and savings on maintenance (replacing lamps), which is especially important for street lighting.

An induction lamp is an electric light source whose operating principle is based on electromagnetic induction and gas discharge to generate visible light. In fact, it is an improved modification of a fluorescent lamp, the main difference from which is the electrodeless design - the absence of thermal cathodes and filaments, which significantly increases the service life.

An induction lamp consists of three main parts: a gas-discharge tube, the inner surface of which is coated with phosphor, a magnetic ring or rod (ferrite) with an induction coil, and an electronic ballast (high-frequency current generator). There are two possible types of induction lamp designs based on the type of induction: 1. External induction: a magnetic ring is located around the tube. 2. Internal induction: the magnetic rod is located inside the bulb. There are two types of induction lamp designs based on the method of placing the electronic ballast: 1. Induction lamp with separate ballast 2. Induction lamp with built-in ballast The electronic ballast produces a high-frequency current that flows through an induction coil on a magnetic ring or rod. An electromagnet and an induction coil create a gas discharge in a high-frequency electromagnetic field, and under the influence of ultraviolet radiation from the discharge, the phosphor glows. Structurally and in terms of operating principle, the lamp resembles a transformer, where there is a primary winding with high-frequency current and a secondary winding, which is a gas discharge occurring in a glass tube.

Extremely long service life (up to 18 years of continuous operation) Light output more than lm/W, compared to LED lamps; High efficiency (0.9); Reduction in luminous flux by the end of its service life by 10-15% (for LEDs, with a shorter service life, by 20-30%); High photo-optical efficiency Flm/W. LEDs have 40-90; The price is 3-5 times lower compared to an LED lamp of the same power; Low heating temperature of the lamp, only degrees Celsius and a wide range of operating temperatures from -40 to +60; Low content of solid mercury - several times compared to conventional fluorescent lamps. Environmental friendliness. Unlike LED lamps, an induction lamp gives a soft and natural light. It withstands voltage surges much better. The disadvantages include the fact that induction lamps require special lamps, as well as their emission of high-frequency radiation

So, induction lamps, compared to LED and fluorescent lamps, have a number of significant advantages. The main advantages are a 2-3 times longer mean time between failures, a longer warranty period, greater light output and more pleasant and natural light, and environmental friendliness. Therefore, at the moment, it is believed that when choosing between LED, fluorescent and induction lamps (lamps), preference should be given to the latter. However, I would like to note that the price of an induction lamp with an E27 base with a power of 20W is approximately rubles, and an energy-saving lamp of the same power, which has already become common, costs rubles. About 120 years have passed since the invention of induction lighting. Today it is widely used in developed countries: USA, Canada; in Latin America, Europe and Southeast Asia. Finally, this technology has come to the CIS countries - Russia, Belarus, Ukraine. Induction lighting is the future of light energy saving.

Ivanov Evgeniy

The presentation addresses the following questions:
- varieties of LED, fluorescent and induction lamps;
- principle of operation;
- Advantages and disadvantages;
- comparative characteristics of LED, fluorescent and induction lamps.

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Electric light sources The work was carried out by student of group SD-21 Ivanov Evgeniy teacher Krivonosova N.V. LED, fluorescent and induction lamps. Their advantages and disadvantages

Fluorescent lamps A fluorescent lamp is a gas-discharge light source in which an electric discharge in mercury vapor creates ultraviolet radiation, which is converted into visible light using a phosphor - a mixture of phosphorus with other elements. The luminous output of a fluorescent lamp is several times greater than that of incandescent lamps of similar power. Fluorescent lamps can last up to 10 times longer than incandescent lamps, provided the power supply, ballast, and switching limits are met.

Varieties The most common are high- and low-pressure gas-discharge mercury lamps. high-pressure lamps are used mainly in street lighting and in high-power lighting installations; Low pressure lamps are used for lighting residential and industrial premises. Low-pressure gas-discharge mercury lamp (GRLND) - is a glass tube with a layer of phosphor applied to the inner surface, filled with argon under a pressure of 400 Pa and mercury (or amalgam). Plasma displays are also a type of fluorescent lamp.

Advantages and disadvantages The popularity of fluorescent lamps is due to their advantages (over incandescent lamps): significantly greater light output (a 20 W fluorescent lamp provides the same illumination as a 100 W incandescent lamp) and higher efficiency; lamp emission spectrum close to natural; variety of shades of light; diffused light; long service life (2000-20000 hours, as opposed to 1000 for incandescent lamps), provided that sufficient quality of power supply, ballast is ensured and restrictions on the number of switches on and off are observed (therefore, they are not recommended for use in public areas with automatic switches with motion sensors ). The disadvantages include: chemical hazard (LL contain mercury in amounts from 10 mg to 1 g); uneven, line spectrum, unpleasant to the eye and causing color distortions of illuminated objects; degradation of the phosphor over time leads to a change in the spectrum, a decrease in light output and, as a consequence, a decrease in LL efficiency; flickering of a lamp with double the frequency of the supply network the presence of an additional device for starting the lamp - a ballast - very low power factor of the lamps - such lamps are an unsuccessful load for the electrical network

LED lamps LED lamps or LED lamps use LEDs as a light source and are used for household, industrial and street lighting. The LED lamp is one of the most environmentally friendly light sources. The LED lighting principle allows the use of safe components in the production and operation of the lamp itself. LED lamps do not contain mercury-containing substances, so they do not pose a danger in the event of failure or destruction. There are complete devices - lamps and elements for lamps - replacement lamps. The LED lamp is an independent device. The lamp body is most often unique, specially designed for an LED lighting source. Structurally, such a lamp consists of a housing, an LED light source and an electronic driver (power converter).

Varieties All types of lamps can be divided into three groups: LED lamps for streets, parks, roads, for architectural lighting. They are carried out in a housing protected from moisture and dust; in addition, the housing usually acts as a heat sink and is made of materials that conduct heat well. Lamps for industrial purposes, housing and communal services and offices. Such lamps are often produced in a vandal-proof design, equipped with a special screwdriver and special screws that protect the housing from unauthorized opening. The diffuser of modern anti-vandal lamps for housing and communal services is made of polycarbonate material, which is tens of times stronger than traditional glass. Lamps for household needs are usually produced with low power, but must meet numerous requirements for lighting quality, electrical safety, fire hazard and, to a large extent, appearance. Often household lamps have replaceable lamps.

Advantages and disadvantages The advantage of an LED lamp is low energy consumption, long service life from 30,000 to 50,000 hours or more, ease of installation, lower body temperature compared to an incandescent lamp with comparable brightness, high mechanical strength, often small dimensions . LED lamps are well suited for lighting museums and rarities, since the lamp spectrum does not contain an ultraviolet component. The main disadvantage is the high price. In addition, if any of the elements fails, the lamp most often must be replaced with a similar one. These shortcomings are most often compensated by energy savings and savings on maintenance (replacing lamps), which is especially important for street lighting.

Induction lamp An induction lamp is an electric light source whose operating principle is based on electromagnetic induction and gas discharge to generate visible light. In fact, it is an improved modification of a fluorescent lamp, the main difference from which is the electrodeless design - the absence of thermal cathodes and filaments, which significantly increases the service life.

Operating principle An induction lamp consists of three main parts: a gas-discharge tube, the inner surface of which is coated with phosphor, a magnetic ring or rod (ferrite) with an induction coil, and an electronic ballast (high-frequency current generator). There are two possible types of induction lamp designs based on the type of induction: External induction: a magnetic ring is located around the tube. Internal induction: a magnetic rod is located inside the bulb. There are two types of induction lamp designs based on the way the electronic ballast is placed: Induction lamp with separate ballast Induction lamp with built-in ballast The electronic ballast produces a high-frequency current that flows through an induction coil on a magnetic ring or rod. An electromagnet and an induction coil create a gas discharge in a high-frequency electromagnetic field, and under the influence of ultraviolet radiation from the discharge, the phosphor glows. Structurally and in terms of operating principle, the lamp resembles a transformer, where there is a primary winding with high-frequency current and a secondary winding, which is a gas discharge occurring in a glass tube.

Main Advantages and Disadvantages Extremely long service life (up to 18 years of continuous operation) Light output more than 80-160 lm/W, for comparison with LED lamps 90-120; High efficiency (0.9); Reduction in luminous flux by the end of its service life by 10-15% (for LEDs, with a shorter service life, by 20-30%); High photo-optical efficiency 120-200Flm/W. LEDs have 40-90; The price is 3-5 times lower compared to an LED lamp of the same power; Low heating temperature of the lamp, only 40-60 degrees Celsius and a wide range of operating temperatures from -40 to +60; Low content of solid mercury - several times compared to conventional fluorescent lamps. Environmental friendliness. Unlike LED lamps, an induction lamp gives a soft and natural light. It withstands voltage surges much better. The disadvantages include the fact that induction lamps require special lamps, as well as their emission of high-frequency radiation

Conclusion So, induction lamps, compared to LED and fluorescent lamps, have a number of significant advantages. The main advantages are a 2-3 times longer mean time between failures, a longer warranty period, greater light output and more pleasant and natural light, and environmental friendliness. Therefore, at the moment, it is believed that when choosing between LED, fluorescent and induction lamps (lamps), preference should be given to the latter. However, I would like to note that the price of an induction lamp with an E27 base with a power of 20W is approximately 700-1000 rubles, and an energy-saving lamp of the same power, which has already become common, costs 100-150 rubles. About 120 years have passed since the invention of induction lighting. Today it is widely used in developed countries: USA, Canada; in Latin America, Europe and Southeast Asia. Finally, this technology has come to the CIS countries - Russia, Belarus, Ukraine. Induction lighting is the future of light energy saving.

Sources http://electrik.info http://ru.wikipedia.org http://belenergetics.ru/ http://so-induction.ru/ http://www.sknews.ru

Over a long period of operation, the advantages and disadvantages of fluorescent lamps were well studied, which made it possible to use them most rationally in lighting devices. Currently, energy-saving devices are gaining great popularity and are widely used in everyday life.

General information

Fluorescent lamps belong to the category of low-pressure gas-discharge light sources. An electric current discharge occurs in a gaseous environment, causing the appearance of ultraviolet radiation, invisible to normal vision. Getting on the walls of the bulb with a phosphor coating, it turns into a visible light flux.

The light bulb itself is made in the form of a cylindrical glass tube, inside of which there is an inert gas and mercury vapor. The ends are hermetically sealed with lids, with electrodes soldered into them. When current is connected, they create an electrical discharge, after which all processes are started, ultimately causing the lamp to glow.

All fluorescent lamps provide a soft, uniform light flux. It is difficult to control and adjust due to the large emitting surface area. The shape of the tubes can be linear, annular, U-shaped, or round. Own configurations are provided for . The diameter of a glass bulb is shown in eighths of an inch. For example, the T5 marking corresponds to 5/8 inch or about 16 mm. In catalogs and international standards, this value is indicated only in millimeters.

Today, over 100 types of general purpose lamps with their own standard sizes are produced. The most widely used devices are those with a power of 15, 20, 30 watts for a voltage of 127 volts and 40, 80, 125 watts for 220 V. The average service life is approximately 10 thousand hours.

All known disadvantages and advantages of fluorescent lamps, their parameters and technical characteristics are directly related to the ambient temperature. The most suitable temperature for mercury vapor is considered to be 40 degrees, at which maximum light output is achieved.

Specifications

The properties of each lamp are reflected in its parameters indicated by the manufacturers in or on the packaging. Usually this information is enough to make the right choice.

First of all, you should pay attention to the supply voltage. For Russian networks, the marking 220-240V/50Hz is provided, which fully complies with generally accepted parameters. In the same way, the power consumption value is indicated on the light bulb. Sometimes the packaging provides a comparison with an incandescent lamp at the same energy consumption.

The high quality of well-known manufacturers determines the advantages of fluorescent lamps in this indicator by 4-5 times. Quite often there is a designation like 16 W = 80 W. This means that with the same luminous flux, a fluorescent lamp will consume only 16 watts, and a regular incandescent lamp will consume as much as 80 watts.

Some advantages and disadvantages are determined by the luminous flux, which indicates the amount of light power relative to the total radiation flux. This value is determined in the laboratory, measured in lumens (lm) and applied to the packaging or reflected in the passport.

Of great importance is the indicator showing how close the glow is to natural light. This parameter is measured in Kelvin and is considered in three ranges:

Warm white range - 2700-3200 K. These fluorescent lamps produce soft white light emission, with a slight yellowish tint and are best suited for residential areas.
Cool white color is in the range of 4000-4200 K. Lamps with such indicators are used to illuminate work areas, offices and public buildings.
The range of daytime white color is 6200-6500 K. It is used in lighting systems for streets, non-residential premises, theater stages and other similar objects. It features a sharp white light with a pronounced cold tone.

When choosing a lamp, be sure to take into account the color temperature. If replaced, the product must have the same characteristics.

Features of operation

Considering the pros and cons of fluorescent lamps, we should dwell in detail on the features of their operation, which differ significantly from conventional ones.

Therefore, when using fluorescent lamps, we must not forget about the following mandatory rules:

These light sources do not tolerate frequent switching on and off. A similar situation is associated with the use of and in the circuit. With each start-up, the electrodes evaporate, as a result, the ends of the tubes begin to turn black. High current consumption by ballasts during starts causes increased loads and premature failure. Therefore, low-power lamps, up to 15 W, are recommended to be turned on and off once a day. If you can’t do without this, you need to buy more expensive lamps with a soft start system that will work without any problems.
Increased sensitivity of fluorescent lamps to voltage changes, especially downward. The starting device begins to consume even more current, otherwise the lamp simply will not start. As a result, frequent low voltage causes premature wear of the ballasts.
Fluorescent lamps require extremely careful handling. First of all, this is due to the mercury vapor contained inside the flask. If not, then harmful substances will enter the environment. Therefore, during transportation or storage, the lamps must be in a reliable, stable position. When replacing the lamp, wear gloves, since traces of fat on the bulb may cause an explosion when heated.
The need to control the duration of operation of light bulbs. For this purpose, the date of commissioning is recorded in a special journal. This is done due to the deterioration of the quality of the luminous flux over time. In reality, this rule is almost never observed and the lamp is replaced only after it fails.
For fluorescent lamps, it is recommended to use open-type lamps. During operation, some of them become very hot, and closing the lighting devices does not provide the necessary ventilation. In addition, the matte surface of the lampshade delays the light flux and transmits it only partially. Open lamps do not heat up at all and create maximum brightness with the same energy consumption.
The energy savings expected to be achieved largely depend on the manufacturer of the fluorescent lamps. Cheap devices are made of the same materials, so the quality of light and service life leave much to be desired. It is better to purchase products from well-known brands that are as close as possible to the stated technical characteristics.

Advantages and disadvantages

Having examined the design and operation of fluorescent lamps, the rules of their operation, their pros and cons, we can draw definite conclusions about the positive and negative qualities.

The undoubted advantages of these products are:

Increased efficiency compared to traditional incandescent light bulbs. The efficiency is several times higher. LED lamps can be a serious competitor, but their high cost hinders their widespread use.
High luminous efficiency, allowing to illuminate large areas indoors and adjacent areas.
Devices with phosphor have a long service life. For some modifications, it amounts to tens of thousands of hours, provided that all rules are followed and there are no frequent switches on and off. They do not contain filaments, which can quickly burn out.
Most models of fluorescent lamps are not subject to strong heating and can be used in lamps where the maximum permissible temperature is strictly limited.
Light is scattered from a large surface area of the lamp and distributed evenly throughout the room.

Negative qualities and disadvantages are manifested in the following:

The mercury contained in the bulb is a dangerous substance, so the lamps require special.
Over time, the properties of the phosphor are lost and its effectiveness decreases. As a result, not only the luminous efficiency decreases, but also the efficiency.
The need to use ballasts, without which the operation of the lamp is impossible.

There are other disadvantages, but they do not have a noticeable impact on the use of fluorescent lamps.

Failure

1. Electrode Spraying

During periodic short-term operation (< 3 ч)

With frequent cold starts

2. Starting equipment failure

Structural faults (defects)

Non-standard work environment

Expiration of operating time

Burnout due to electrode sputtering

Spraying phosphor

Absorption of mercury vapor

Advantages

Efficiency

Efficiency = 22% (for incandescent lamps 5-10%)

ψ = 16 – 100 lm/W (average 50-67 lm/W)

Durability

10-20 times longer compared to incandescent lamps

More uniform luminosity

Lower heat dissipation (65-75%)

Reduction in size, price and power of air conditioning

Flaws

Health problems

Possible mercury vapor poisoning

Problems for people with increased sensitivity to UV, epileptics, and chronic fatigue syndrome

Headaches and fatigue

The need to use starting equipment

Price increase

Possible low frequency hum

Reduced power factor

RF noise

Distortion of electricity parameters

Dependence on environmental parameters

Flickering and possible stroboscopic effect

Difficulty in reusing and recycling

An LED is a semiconductor device that converts electrical current directly into light radiation. In English, an LED is called a light emitting diode, or LED.

LED design

LED consists of a semiconductor chip on a substrate, a housing with contact leads and an optical system. Modern LEDs bear little resemblance to the first packaged LEDs used for display.

LED design

Glow occurs when electrons and holes recombine in the region of the pn junction. This means that first of all we need a p-n junction, that is, contact between two semiconductors with different types of conductivity. To do this, the near-contact layers of the semiconductor crystal are doped with different impurities: acceptor impurities on one side, donor impurities on the other. However, one pn junction in a crystal is not enough, and it is necessary to manufacture multilayer semiconductor structures, so-called heterostructures, for the study of which Russian physicist academician Zhores Alferov received the Nobel Prize in 2000.

LED design

Unlike an incandescent or fluorescent lamp, electrical current is converted directly into light radiation, and theoretically this can be done with almost no loss. The LED (with proper heat dissipation) heats up little, which makes it indispensable for some applications. Further, the LED emits in a narrow part of the spectrum, its color is pure, which is especially appreciated by designers, and UV and IR radiation are usually absent. The LED is mechanically strong and extremely reliable, its service life can reach 100 thousand hours, which is almost 100 times longer than an incandescent light bulb and 5 to 10 times longer than a fluorescent lamp. Finally, the LED is a low-voltage electrical device, and therefore safe.

Main characteristics

Material: Silicon compounds

Consumes 2 to 4 V DC voltage

Efficiency: 93-94%

Luminous flux, lm: from 7 to 1200

t g.wed. = 100,000 hours

Advantages

Ultra long service life

Low power consumption

Low temperature operation

Resistance to mechanical stress

High luminous efficiency

Environmental and fire safety

Flaws

Great cost

When connecting the LED, the polarity must be observed.

LED bulbs
Comparison of fluorescent lamps and LED lamps
Technical	LED lamp	Fluorescent Lamp
characteristics
Light source	SMD LEDs(3528)	Phosphor
	Manufacturer
	Semileds LEDs
	(Taiwan) 180 pieces
	Cold white	Cold white
Colorful temperature
Operating voltage
Operating frequency
Power
Luminous angle

	Optical polycarbonate
Guarantee
Life time	100000 hours

1. Electric lighting	SAEES
		the tightness is broken, and if constantly
		exposed to the harmful effects of mercury vapor, then they
		will accumulate in the human body, causing harm
		health. Requires special disposal.
Flaws	Higher
		Dependence of light characteristics on temperature
		environment