Why and how hot do LED lamps get?

Poor quality LED lamps

Take a closer look at the product costing from 125 rubles.
Anything cheaper is outright rubbish. Such lamps have a low-quality LED board that is not capable of dissipating enough heat. A bad case is also associated with “thermal” problems; they don’t even have the simplest driver. Power is provided through a ballast capacitor; no stabilization or protection is provided. In recent years, such specimens have gradually disappeared from the market. Install a varistor with an operating voltage of about 470 V in parallel with the lamp. This will reduce the risk - it will extinguish high-voltage surges.

You can improve such a light source by increasing the capacity of the filter capacitor on the board and installing a fuse if there is none.

A few words about the design

LED lamps are a complex electronic device, the design of which is divided into several parts:

• Diffuser. It is a glass or plastic flask that serves to uniformly disperse the light flux.
• The chips are light-emitting diodes.
• The printed circuit board is the platform on which the LEDs are mounted. Made from material with high thermal conductivity.
• The radiator is a structure made of material with high thermal conductivity. Serves to remove heat.
• The driver is an LED power supply, used to convert the alternating voltage of a 220-volt electrical network into the power necessary for the normal operation of the LEDs.
• The socket is an important element that serves to connect the light bulb to the lamp socket.

It is clear from the design that the LED lamps heat up, and to remove the generated heat, a radiator made of a special material with high thermal conductivity is installed.

The radiator in an LED light bulb is designed to remove heat from its only heating part - a group of LEDs. In this light fixture, neither the bulb nor the base heats up (provided there is normal contact with the socket). The release of thermal energy occurs only on the LED crystals, and heat is removed from them.

Heating temperature of LED lamps

An LED lamp, like all devices that convert electric current into light, generates some heat. Light sources based on LEDs heat up several times less when compared with incandescent lamps. In an LED lamp, neither the base nor the diffuser heats up. Heat is generated only on the LED crystal itself, and most of the heat is generated by the driver. Thermal energy is transferred to the radiator and is successfully dissipated by it.

It is important to understand how much LED lamps heat up for those who plan to use them near flammable objects - suspended ceilings, furniture, curtain lighting, etc. The heating intensity depends on the power and it is logical that a less powerful LED heats up less. The actual efficiency of lamps is estimated at 80%

The actual efficiency of the lamps is estimated at 80%.

Those. with an LED lamp power of 10 W, 2 W will be spent exclusively on heat generation. The heating temperature of an LED lamp reaches only 65 °C at its maximum hot point, compared to incandescent lamps, the temperature of which easily reaches 265 °C. So, when asked in stores “which light bulbs don’t heat up?” - meaning LED.

You also need to remember that the LED lamp has elements that heat up much more. Thus, the capacitor can heat up to more than 100 °C. And this is its absolutely normal operating temperature. The capacitor is placed on the driver and covered with a housing; it is impossible to remove it without damaging the structure.

As a result, we can identify several factors that determine how hot LED lamps become:

• The quality of materials of both the radiator and all components;
• Lamp power;
• Build quality;
• Ambient air temperature.

Lamp operating temperatures:

— Incandescent – ​​depending on the power, the temperature can exceed 200 oC

- Halogen - they heat up even more than incandescent lamps, more than 250-300 oC - Fluorescent - ~70 oC - LED LED - ~60 oC Of course, the exact temperatures are highly dependent on many factors, in particular on power, but these indicators give a general understanding

It is important to know that LED and fluorescent lamps heat up slightly during operation; household models can be touched with your hand, even if they have been turned on for a long time. And halogen and incandescent lamps, due to the principle of operation, are directly hot. Because of this, they have restrictions on places and methods of installation.

Despite significantly different temperature conditions, each of these species is harmed by excessive heating, beyond the calculated values. The explanation for this is simple, it doesn’t matter whether the lamp is designed for a maximum temperature of +50 degrees or +500 oC, exceeding these temperatures is equally harmful to both

Because of this, they have restrictions on places and methods of installation. Despite significantly different temperature conditions, each of these species is harmed by excessive heating, in excess of the calculated values

The explanation for this is simple, it doesn’t matter whether the lamp is designed for a maximum temperature of +50 degrees or +500 oC, exceeding these temperatures is equally harmful to both

The main consequence of overheating is a significantly reduced service life and sudden failure of the lamps. Since elevated temperatures destroy their structure, change the chemical composition and physical state of the elements, all this generally leads to early burnout of light bulbs.

Overheating is one of the 7 main reasons why light bulbs burn out; read more about the other 6 factors HERE.

Are there light bulbs that don't get hot?

Choosing a lamp that is guaranteed not to overheat and cause trouble to the owner is an important task. If the apartment has a suspended ceiling made of PVC film, the hot surfaces of the lamps will quickly damage the canvas. Of all the existing types of lamps, only two types can be used:

Interesting! It is impossible to find a lamp that does not heat up at all. However, you can choose a lamp with the lowest operating temperature. As a rule, these are lamps made by well-known and reliable manufacturers, usually from Europe. The cost of such devices is quite high, but the degree of reliability is much higher than that of the products of most Chinese companies.

Useful tips Connection diagrams Principles of operation of devices Main concepts Meters from Energomer Precautions Incandescent lamps Video instructions for the master Testing with a multimeter

Why does an LED lamp burn at full intensity - features of the design and operation of the lamp

The design of an LED lamp consists of a base, driver, radiator, bulb and board with LEDs. The light source is powered through an alternating electric current network, the voltage of which is reduced by the driver. The radiator is responsible for removing heat from the LED elements - they heat up when the lamp is on. If an LED lamp is used instead of a traditional incandescent or halogen lamp, it is necessary to select the power and brightness corresponding to the previous light sources and luminaire.

These features of the operation of LED lamps make it possible to understand why the LED lamp burns at full intensity. It is worth noting that a frequent search on the Internet that includes the word “in full swing” is incorrect. The correct word to use is “full heat”.

Driver Significance

Any LED, regardless of its application, must have a stabilized rated current (nameplate value) flow through it. Only in this case will the glow be even, and the operating time of the crystal will be able to exceed the mark of 10 thousand hours. Regardless of the shape, size and number of LEDs, all LED lamps can be divided into two main categories according to the control method:

• based on a driver with a pulse load current driver;
• based on a ballast voltage source.

A driver with a pulse transformer and a current converter is the only correct technical solution for powering LED lamps, which is produced industrially.

To appreciate the importance of a current stabilizer, let's look at its operating principle using a short example. In ceiling chandeliers with LED lighting, as a rule, a current stabilizer unit is installed. Its output voltage varies over a wide range, and the output current value will remain constant even with one LED in the load.

In such a chandelier, a burnt-out LED can simply be short-circuited. More powerful current drivers operate on approximately the same principle.

Its output voltage varies over a wide range, and the output current value will remain constant even with one LED in the load. In such a chandelier, a burnt-out LED can simply be short-circuited. More powerful current drivers operate on approximately the same principle.

Considering that the production of LED light bulbs with a pulsed current driver is not entirely economically justified, Chinese entrepreneurs decided to simplify its design. Instead of a driver, a ballast power supply without a current stabilization function is installed in the LED lamp housing. Its output voltage is calculated based on the number of SMD LEDs inside the case. As a result of voltage drops in the network, the glow power of the lamp changes. And frequent phase jumps up to 240 V lead to LED lamps burning out.

The essence of light

Light, as a physical phenomenon, can have various manifestations. In different light, we will see objects and the reality around us in different shades, which will undoubtedly affect our worldview. At the same time, we can perceive objects more clearly or distortedly. Color temperature and color rendering index are responsible for the correct lighting and how we perceive the surrounding space.

LED lamp glow

The color temperature of LED lamps must meet certain requirements so as not to cause inconvenience. This is the main characteristic of any type of light bulb, especially those that are capable of heating. It is worth noting that LED light sources are capable of very minimal heating. Therefore, even though they can get a little warm, they are actively used in tandem with stretch ceilings. Color temperature determines the spectral composition of light radiation, which must be objectively perceived by human visual analyzers (eyes). This indicator is measured for LED lamps, as with other light sources, using a colorimeter. And it is measured in inverse microdegrees or mireds. When choosing LED models, the consumer must be familiar with this indicator in order to make the right purchase. There is a corresponding table to determine the optimal color temperature range.

Color temperature table

When choosing a light source for your home, street or car, you must remember that the light emitted by the light bulb should be as close as possible to the natural level of illumination.

Where to buy LED lamps for a car?

There are many companies on the Russian Internet that sell LED lamps for many cars. But we intend not to advertise such stores. The fact is that, despite a decent assortment of LED lamps in Russia, still, compared to foreign online stores, the presented volume of lamps for various cars in our country is not huge.

And taking into account that the average age of cars in Russia is 12-15 years, many owners, wanting to install LED lamps on their car instead of halogen ones, are unlikely to find in Russia where to buy a set of equipment, front optics with LED lamps, specifically for their old one car. .

If you think that you can’t change halogen lamps to LED lamps on your own, then you are mistaken. Believe me, the retrofit kit can be installed even by a car owner who has never opened the hood on his own.

The only thing that a car owner may encounter when changing halogen lamps to LED lamps is difficulties associated with access to the lamps. In some vehicles (depending on the make and model), the headlight bulbs are difficult to access.

Tip: When removing the halogen bulbs from the headlights, do not touch the glass bulb with your bare hands. Bare fingers can leave dirt on the bulb, resulting in reduced light scattering. After all, there is no point in damaging halogen lamps since they are in working condition. It is quite possible that they will still be useful to you. For example, if you don't like the way LED lamps shine, you can return the halogen ones to their place.

Also, when replacing halogen bulbs with LED bulbs, make sure your headlights are adjusted correctly. Remember that properly calibrated headlights can effectively direct light onto the road, capturing as much of the road as possible without blinding oncoming traffic.

As a rule, headlights are adjusted using special screws located on them. You can adjust the headlights at a car service center on a special stand, or adjust them by eye. To do this, drive slowly up to the wall and turn on the low beam. Adjust the headlights according to the beam of light so that the beam of light does not shine too high or low.

Additional functions

Depending on the manufacturer and model, the LED manicure device includes additional functions:

Timer

LED drying devices with a timer allow the master not to focus on time - the lamp itself will inform you when drying is finished by sounding a beep or turning off the light inside. Usually the timer is programmed for 15,30 and 60 seconds, but there are manufacturers whose devices have a different step

For example, Kodi programmed their dryer for 30, 60 and 90 seconds.

Display. The drying time is displayed on a small screen, which serves as an additional reference point for control.

Bottom. Externally, nail dryers differ in design and the presence of a bottom. There are devices with a familiar design - cases with a bottom, inside of which diodes and lamps without a bottom are installed - in this case, the hands are placed on the manicure table.

Sensor. Sensor devices do not allow you to start the lamp manually - they do it automatically when you place your hand in the glow area. Several devices with touch control are presented by the SUN brand, for example the LED lamp 54 w SUN5 plus.

Are LED headlights in a car repairable?

Nothing lasts forever in our world. Including light bulbs in car headlights. But what's the problem? I bought a new one and changed it. Yes, this is true when it comes to conventional halogen or xenon lamps. But what to do if the LED lamp or headlight goes out? Fortunately, it can be repaired.

LED lamps in both rear and front lights are becoming a standard in the automotive industry, rapidly replacing conventional lighting sources. LEDs have become popular in the automotive world due to their energy efficiency and, of course, brightness. Many LED headlights have better performance than expensive xenon adaptive optics.

But with the massive arrival of LED lamps in the automotive industry, a problem appeared related to the breakdown of LED light sources. As a result, many users today are wondering: what to do if the diode fails? Can it be replaced like a regular incandescent lamp? We have two news for you - good and bad.

In theory, diodes should be more durable than traditional light bulbs. And this is true, BUT under ideal conditions. Unfortunately, LED car headlights/bulbs are not as resistant to shock and moisture compared to conventional halogen or xenon light sources. Therefore, the LEDs in the car fail quite often. In addition, diode headlights are usually designed in such a way that they cannot be disassembled and one light element cannot be replaced (one diode, which, for example, has burned out).

This is why if several LEDs in a headlight in your car are not working, the official dealer will usually suggest replacing the entire headlight, telling you that the headlight is service-free. And so it is. The thing is that usually the diodes are fixed (soldered) on a single board. Therefore, according to the technical regulations of many automakers, in the event of a malfunction of the LEDs on the board, it is recommended to replace the entire lamp with a new one, which is very expensive.

Fortunately, the market does not sleep, and very quickly various specialized workshops that deal with automotive LED lighting began to appear in our country. True, the cost of repairing LED headlights is not cheap. But nevertheless, this is still better than purchasing an expensive original new headlight. For example, a new LED rear headlight on a Mercedes E-class (W212) costs more than 20,000 rubles. A non-original Taiwanese headlight costs a little more than 10,000 rubles.

The cost of repairing a taillight is 5000-6000 rubles. As you can see, it is more profitable to carry out repairs than to purchase a new flashlight. However, no matter how professional the repair may look, it should be remembered that officially, according to the recommendations of automakers, it is technologically impossible (theoretically) to carry out such repairs with high quality.

So don’t be surprised that to repair an LED headlight, specialists can begin to break the hermetically sealed lamp, drill, re-glue the glass, etc. The fact is that not every LED headlight housing can be divided into two parts. In this case, craftsmen have to literally cut the lantern, carry out repairs, and then glue it together for a long time. You understand that you will not get 100% quality in any case.

Please also note that repairing diode car headlights, due to their design, is closer to electronics repair than auto mechanic repair. Also keep in mind that the cost of replacement parts for LED lights is low.

But due to the complexity of dismantling the board, the cost of repairing LED optics can be a considerable amount. Especially when it comes to a faulty front LED headlight.

However, in any case, the cost of repairing diode optics will cost you less than buying a new original headlight.

This is interesting: What is LED degradation - expert advice

Conclusion

As a result of overheating, the LED inevitably fails. Either its service life is greatly reduced, or it “burns out” instantly. To solve this problem, it is necessary to use a driver whose circuit ensures not only maintaining a stable current, but also reducing it to maintain a stable temperature, or a circuit that will turn off the lamp in case of overheating (with thermal protection), thereby maintaining its serviceability.

There are two problems in creating “long-lived” LED light sources:

1. Manufacturers of budget products do not provide gentle operation of LEDs. On the contrary, in some cases they do not operate in nominal mode, but in overloaded mode. That is, the lamp after purchase shines very brightly, which impresses the end user, but soon it gives less and less light.

2. The design of modern lamps implies an aesthetic appearance and it is not possible to fit a radiator into this concept. Therefore, the cooling requirements for LEDs are not met. In this case, it is possible to ensure their operation with a current lower than the rated one, which will lead to a significant reduction in heat generation, but due to the reason described in the first reason, this is again impossible.

Unfortunately, there are no specific recommendations for choosing quality products. The only universal solution would be to purchase products only from well-known brands. When making LED lamps yourself, you should take into account what was said above regarding power supply and cooling of LED products.

What to do if the light bulbs in the chandelier explode when turned on?

Many people have encountered a problem when, when turning on the light in a room, an incandescent lamp suddenly explodes with a bang. Naturally, this is unpleasant - there is fear, and darkness in the apartment, and even the base from a burst lighting fixture must somehow be removed from the socket. But removing the part remaining in the lamp is only half the battle. It is necessary to understand why light bulbs in a chandelier explode when turned on and how to avoid such incidents in the future.

Of course, the main and most common cause of such pops is the low quality of the product, i.e. incandescent lamps. But this is the simplest reason, which can be eliminated by replacing the lamp, and therefore you should not dwell on it seriously. But if the lamps have been changed more than once to devices from different manufacturers, but the problem remains, you should dig deeper.

Obvious factory defect of the lamp. Such a base cannot be screwed into the socket

Reason No. 1 – ceiling ventilation

When an incandescent lamp operates, a lot of heat is generated. Naturally, it needs a way out, and if you imagine that there is a dome over a working lighting device that prevents heated air from rising upward, trapping it, then you can understand that the lamp is constantly overheating, and this happens quite quickly. This will not happen if you install LED lamps, since they have good heat transfer.

In this regard, with constant temperature changes, the base is separated from the bulb due to the destruction of the adhesive base, and the moist air that gets inside when heated again destroys the lamp tube. As a result, naturally, it ends up inside the flask and an “explosion” occurs.

Eliminating the cause

It is easy to eliminate such a cause. The ceiling ventilation needs to be improved. If it is metal, simply drill a few neat holes in the back to restore air circulation.

Perfectly ventilated lampshade. This way the lamp will heat up less

Reason No. 2 – network voltage

This reason should be discussed in more detail, since it is caused by several factors. The question may arise as to why household appliances and electronics do not burn out during sudden power surges. Everything is simple here - all modern devices are equipped with stabilization or protective devices that are quite capable of containing short-term sharp surges in voltage, and after the surge, working, for example, at an increased current, albeit with a load, they continue to work quite tolerably.

But with incandescent lamps it is a little more complicated. The voltage from the network goes directly to the device, without any protection, and therefore such a light bulb takes the entire blow.

In addition, there is one little secret, knowing which, you can make sure that light devices with an incandescent filament continue to work even after power surges, provided, of course, that they are not too large.

Elimination

Anyone who has encountered connecting a cartridge to the network knows that power comes to it through two wires. But usually no one attaches importance to which wire is connected to which contact.

But this is important, and manufacturers of incandescent lamps produce them according to a certain scheme. It provides for the fact that the phase wire must approach the central contact of the cartridge, and the zero wire must approach the peripheral one

It is the correct connection that can help an incandescent lamp not explode.

Schematic illustration of the correct connection of an incandescent lamp to the network

Reason #3 – bad contacts

It makes sense to inspect the input cabinet, and most carefully, the connection of the neutral wires, since this is the weakest point and a very common cause of various troubles. If there is poor contact between the neutral wire and the neutral block, there is a constant change in the voltage in the network, and sometimes quite sensitive.

Such jumps are especially noticeable if any powerful device is turned on on the same pair (phase-zero). Just when it is turned off, a sharp surge in voltage occurs due to the fact that with poor zeroing, the voltage in the network does not have time to stabilize. As a result, the weakest link in the chain usually fails, and this, naturally, is an unprotected incandescent lamp.

Elimination

To prevent this, it also makes sense to install a dimmer instead of a switch and a stabilizing device at the input.

This is interesting: How to properly attach drywall to a profile - detailed instructions - we explain in detail

Burnt smell due to lamps

Lamps are often the cause of a burnt smell. The palm here, of course, belongs to incandescent lamps (we will explain why below), but compact fluorescent (CFL, “energy-saving”) and LED lamps can also be a source of disturbing odors.

Traditional incandescent lamps, as well as halogen lamps (which are essentially a modification of an incandescent lamp), during operation, emit an impressive amount of heat and intensely heat surrounding objects.

The use of 150-watt incandescent lamps can not only cause a burning smell, but also lead to more serious consequences.

Compact fluorescent lamps (CFLs, “energy-saving” lamps), despite the bravura speeches of manufacturers, sellers and government officials (!), who at one time actively used administrative resources to push these dubious products onto the market, did not at all justify the advances they were given. Due to the poor quality of electronic components and careless soldering, some copies overheated and smelled bad. Another characteristic sign of such a low-quality lamp is the rapid yellowing of the base during operation.

“Energy-saving” lamps, it seems, are already living out their short life without defeating the good old Ilyich light bulb, but the consumer still has to suffer with LED lamps.

Despite the fact that LED technologies (LED technologies) are, not without reason, considered a new progressive word in lighting technology, their implementation comes with various costs, excesses and “childhood diseases”. In any case, there are quite a lot of complaints about the unpleasant odor from LED lamps. In addition, we have more than once witnessed situations where a short circuit in the base of a diode lamp led to electrical accidents - power outages to rooms or individual groups due to the operation of circuit breakers.

Overheating of the power supply: main causes and options for eliminating them

Modern TVs from all well-known manufacturers are equipped with switching power supplies. The devices are compact in size, allowing them to be built directly into the receiver body. Each manufacturer has its own power adapter circuit, but the internal components are the same - capacitors, diodes, transformers. All semiconductor elements are made on the basis of silicon, which begins to self-destruct at temperatures above 150 degrees. Therefore, overheating of the power supply can lead to failure of various TV receiver modules: processor, control board, external interfaces (antenna input, USB and HDMI connectors).

Visually, the malfunction can be determined as follows:

• The power light on the case does not light up;
• the TV turns on late or turns off after several minutes of operation;
• The back cover in the area where the power cord enters is very hot.

During operation, any power supply unit generates heat, which is considered absolutely normal. But if you can’t touch it with your hand, this is a clear indicator of a breakdown.

The reasons why the power supply gets very hot may be the following:

• heat exchange is disrupted;
• electrolytic capacitors have dried out;
• the network cable is damaged;
• unstable voltage;
• The power transistor has failed.

In most cases, you will not be able to solve the problem yourself, since you will need to open the TV, resolder the power supply, or completely change the module. If you do not have sufficient qualifications or are not sure that you can fix the breakdown on your own, call a specialist. Our service center engineers will perform diagnostics, determine exactly where the problem is, and promptly fix it at your home.

Quality

The first reason is the low quality of the product itself and its components. If you buy cheap copies, then don’t be surprised that in just a few months you’ll run back to the store for another device.

And so on from year to year. For long-lasting ceiling lighting, it is not recommended to skimp on such a component. The same applies to the tape itself.

How to distinguish a high-quality LED strip from a cheap one, in detail with all examples, is described in another article.

Which lamp to use in a suspended ceiling made of PVC panels

Spot lighting in suspended structures made of PVC panels (or suspended ceilings) must meet a number of requirements. The main thing is the heating temperature of the lamp and the lamp body. The material of the ceilings in question, having low heat resistance, under the influence of high temperatures can turn yellow, become stained, crack and lose elasticity. You can protect yourself from these deformations by choosing the optimal light source. Based on my personal example, when choosing between a halogen or LED lamp, the latter option turned out to be optimal.

Having determined that the heating temperature of LED lamps is low, and the price is 2-3 times higher than halogen samples, it is additionally recommended to study a full comparative analysis:

In conclusion, it is worth noting that the solution to the problem with halogen lamps that get very hot was to replace them with LED energy-saving lamps. The specific model is presented in the title image of this material (estimated cost 65 rubles). Its power is 5 W, which corresponds to 35 W for halogen. As a result, the lamp hardly heats up, and the light is brighter compared to previously installed halogen lamps with a power of 50 W. Also, when halogen lamps were working, the space above the ceiling was so illuminated that the PVC panels were visible through. With LEDs these gaps disappeared.

Main conclusions

LED lamps heat up during operation, like all other types of lamps. However, the degree of heating is significantly lower than that of other designs. It depends on various factors:

• lamp power;
• quality of crystals;
• lamp operating mode.

There are no designs that do not heat up at all during operation. The efficiency of any lamp clearly demonstrates the relationship between the luminous flux and the dissipation of applied energy, which is dissipated in the form of heat. LED devices usually heat up to 60-70°, which does not pose a fire hazard and does not damage the stretch ceiling fabric. Express your opinion about heating LED lamps in the comments.

How hot can an LED strip get?

Under normal operating conditions of the LED strip in residential premises, the surface should not heat above 45-50°C. A person’s hand can be used to determine the degree of heating; warmth is felt when touched; the elements can be held for a long time without the risk of burns. Due to the reduced temperature of the elements, high fire safety of the product is achieved. At the same time, energy savings are ensured, since LEDs are designed for low operating current.

When manufacturing an LED assembly in a sealed casing, the heat transfer of the elements deteriorates. To ensure cooling, it is necessary to install radiators located in the air flow area. Increasing the brightness of the glow leads to an increase in energy consumption and an increase in the temperature of the LEDs. Special products with increased brightness allow long-term operation at a temperature of 120°C. There are experimental developments that allow you to maintain performance when heated to 200°C.

Why is the issue of thermal conditions so important?

Increased heating of the LED strip affects the performance of the product and light characteristics, and also negatively affects the parameters of the strip during the life cycle. During short-term overheating, reversible processes occur associated with a shift in color temperature or a decrease in light output.

The dependence of the brightness of the glow on temperature can be seen on elements of yellow and red colors; blue LEDs are the least sensitive to overheating. Tape manufacturers calibrate products on the RGB scale based on brightness and color measurements at a fixed temperature of 25°C. During testing, a short current pulse (25 ms) is applied, which does not affect the temperature background of the elements. During prolonged operation, the LED heats up, which reduces the brightness compared to the declared value.

Prolonged operation at elevated temperatures accelerates wear of the LED, which further reduces the brightness of the light. Laboratory tests have shown that an increase in operating temperature by 11°C leads to a reduction in the service life of the product by more than 2 times. There are LEDs designed for operation at elevated temperatures (up to 100°C). For example, products with white light have a service life of up to 50 thousand hours. But when the safety margin is developed, the brightness of the products drops by 70%.

Tuesday, January 17, 2012

Do LEDs get hot?

Everywhere they say that LEDs practically do not heat up. So why do LED devices need a heat sink and what happens if there is no heat sink? The so-called pn junction of the crystal glows in the LED. Roughly speaking, this is the place where one type of metal (-p) connects to another type (-n). The task is to find such a combination of different conductors so that as much light as possible comes out of this zone with minimal losses. And this is where the problems begin. The ideal combination of -p and -n conductors has not yet been found, and it is unlikely that they will be found, and there will always be losses, whether we like it or not. Therefore, along with particles of visible light, a small amount of heat is also emitted. In the past, when LEDs were so dim that they were used only for display, no one counted this emitted heat - it was so negligible. Now, with the advent of powerful and super-powerful LEDs, the ratio of light and heat emitted by the crystal has remained the same, but now it is more noticeable. For clarity, look at a regular ordinary microcircuit. Let's say this is a chip measuring 1 by 1 cm. The more tasks this chip performs, the hotter it heats up. But if it is a simple microcircuit, the chip body itself, as well as the metal pins-contacts with which it is soldered to the board, can serve as a heat sink. If we want to place millions of times more semiconductor elements inside the same microcircuit and force this microcircuit to perform millions of times more operations, the heat generation will increase many times and we will need to cool it forcibly. To avoid going far, look at any of the current computer processors - they are all equipped with an aluminum or copper radiator with forced airflow by a fan. About the same thing happens in the LED. When we try to “squeeze” more light from the same chip area, the amount of heat generated inside the crystal itself increases proportionally. And to remove it, you need cooling. Thus, powerful LEDs of the “piranha” type only need their own housing and a printed circuit board on which the LED is mounted as a heat sink. But for a super-powerful LED, additional cooling in the form of a radiator will be required. But where does this heat come from? In an LED, as already mentioned, there are losses during the conversion of electricity into light. But some of this light (photons) remains inside the crystal. For crystals where relatively a lot of light comes out and little remains inside, the definition of “high quantum yield” is applied. If the LED itself is not bright enough and there are relatively few “output” lumens per watt of applied voltage, then the definition of “low quantum output crystal” is applied here.

So for any average LED, the chip temperature always increases along with its power. The typical operating temperature of LEDs produced today ranges from 50°C to 120°C, and given the constant development of technology, it may reach 200°C in the near future. If powerful LEDs are combined into some kind of assembly, and even installed in a sealed housing, then the heating becomes significant. And if heat does not dissipate, the semiconductor junction overheats, which changes the characteristics of the crystal, and after some time the LED may fail

So it is very important to strictly control the amount of heat and ensure efficient heat dissipation. The thermal characteristics of devices are calculated already at the design stage, which eliminates any problems in operation

A few words about the design

The design of an LED lamp differs significantly from traditional lamp designs. LED designs are semiconductor devices in which light is produced through the recombination of electrons at the boundary of the pn junction. The light source is a crystal consisting of three ultra-thin plates forming a pnp junction. When an electron comes into contact with the boundary, a photon of light appears each time. To obtain even and stable radiation, it is necessary to create the thinnest middle layer possible, which contributes to the creation of a tunnel effect. One such crystal is capable of producing a limited amount of light flux, but when several elements are connected, the radiation increases noticeably.

Each lamp contains several crystals (chips). They are installed on a printed circuit board, which is an aluminum plate. The board is attached to a heatsink that removes heat from the crystals. A driver is installed inside the radiator - a power supply that converts 220 V AC mains into 12 V DC voltage. The driver design is based on PWM modulation, which makes it possible to make the circuit miniature, fitting into a bulb.

A plastic base made of a material with high dielectric properties is installed between the radiator and the base. The chips and printed circuit board are covered with a transparent (most often matte) plastic cap that protects the chips from mechanical influences. Most LED devices are made in the traditional form factor of incandescent lamps, which allows them to be installed in old and familiar chandeliers.

Electrical wiring fault

Faulty electrical wiring causes intermittent interruption of the voltage supplied to the lamp. If the contact is broken in the socket, switch or distribution box, then power outages are observed in the network, and the reactive elements of the LED control circuit cause a voltage surge that is dangerous for the LED.

Motorists often have to deal with this problem after replacing lamps, when, under the influence of high temperatures, the spring contacts sinter and lose elasticity, which is why the LED burns out itself and can cause a fire in the entire wiring of the car.

Faulty electrical wiring is a common cause of burnout even for expensive and high-quality LED lamps. The problem is not the quality of the LEDs - the problem is poor electrical contacts.

Overvoltage and overheating

Overheating of LED lamps in a car can be caused by low-quality lamps or drivers included in the electrical circuit. As practice shows, only “premium” class lamps do not suffer from this problem.

If we compare expensive and budget LEDs, then at the same power level the latter can shine much brighter. But this does not mean quality: most likely we can talk about their short service life.

Important! LEDs in the car also burn out due to poor and poorly thought-out air circulation, which leads to overheating

Common breakdowns

Why do fuses blow?

1. When combustion is complete, one or more diodes in the chain are released, the circuit is broken, and the lamp goes out completely.

2. In case of partial burnout, a specific chain fails, which leads to a drop in the brightness of the lighting.

3. Flickering of a strobe is a typical failure for LEDs, which is explained by overheating of semiconductors when there are problems with their power supply.

Modern cars are equipped with intelligent control units for LED headlights, making it possible to optimally regulate the lighting power, and some models of lighting equipment have motorized suspensions that, at the command of the automation, divert the light flux to the side, which prevents dazzling drivers of oncoming cars.

In fact, despite the manufacturer’s assurances about the durability of such headlights, they still often fail, while their repair consists of replacing burnt-out LEDs, and the cost of such work will be extremely high, and many car owners cannot afford it. To prevent such problems, you must first monitor the condition of the electrical wiring in the car.