LEDs for headlamps characteristics. Power source type. Exposure to external factors

The American company CREE is a leading manufacturer of solid-state light sources. The LEDs of the XLamp family of the XR, XP, MC series developed and produced by it are highly efficient and economical, which makes it possible to create modern technologically advanced and environmentally friendly lighting devices on their basis.

So let's decipher the notation a little.

For example, the flashlight says: LED CREE XP-E R2

CREE is naturally the name of the diode manufacturer

XR-E, CREE has XP-E, XP-G, other companies have P4, P7, etc. - this is the designation of the diode itself.

R2 - brightness bin. Bin shows how many lumens the LED produces when consuming 1 watt of energy, for an LED this is a current of 350 mA. In English this parameter is called flux bin. Currently there are Q2, Q3, Q4, Q5, R2, R3, R4, R5, S2. The table below shows how many lumens can be obtained from which diode.

Q2-Q5 and R2 are available for XR-E diodes, R2, R3 are available for XP-E, R4-R5 and S2 are only available for XP-G.

What is the main difference other than brightness?

XR-E is the oldest and is found only in flashlight models that have been on the market for quite some time. XR-E is externally very easy to identify, it has a large hemisphere covered by a diode, the crystal itself is larger than that of subsequent series (for comparison on the XP series it is just a droplet, size XP-E compared to the XR-E was reduced by 80%. XP-E differs from XP-G in that the E has three stripes on the diode, the G series has four, it turns out that the area of ​​the XP-G is larger.

Consequently, in reflectors of the same size and structure, the longest-range one is XP-E, since it has the most small crystal, and, the smallest light source, since it is easy to focus into a narrow beam, then the XR-E, and the widest beam is the XP-G, not because of the size of the crystal, but because of the difficulty of focusing, more on that below.

If the diodes are arranged according to energy efficiency from weakest to brightest, we get XR-E - XP-E - XP-G, where the latter is the most energy efficient, see the table below.

It would seem that if there is the brightest and newest and most efficient XP-G diode, then why are all the well-known and respected flashlight manufacturers in no hurry to switch to this diode. The reason is simple. Each diode requires a specially designed reflector to produce an acceptable light beam.

Let's look at all the series. If you shine a flashlight on a flat wall, you will see the following artifacts:

U XP-E- an ideal picture without any flaws: a well and evenly focused central beam and smooth side illumination without dips.

U XP-G When focusing using a reflector, a so-called donut hole can be observed, when the central beam of light looks like a donut with a noticeable darkening inside. This is not the fault of the flashlight manufacturers, but a feature of the diode. Therefore, companies such as Fenix, Jetbeam, Nitecore, Zebra, 4sevens were in no hurry to update their lineup, while others, in the race for new products, either installed a highly textured reflector, or simply used reflectors for other types of diodes. All this negatively affects the focusing of the beam and the range of the flashlights. According to many experts, flashlights using this type of diode are inferior in range to older models using XP-E and XR-E.

XM-L- is a real masterpiece of this company! This is the latest development of 2011! Since the invention of this LED, 95% of powerful flashlights are built on it! This diode has outstanding characteristics. Its brightness reaches up to 1000 lumens at a current of 3A!

Since invention electric lighting Scientists created more and more economical sources. But a real breakthrough in this area was the invention of LEDs, which are not inferior in luminous flux to their predecessors, but consume many times less electricity. Their creation, starting from the first indicator element and ending with the brightest “Cree” diode today, was preceded by great amount work. Today we will try to analyze the various characteristics of LEDs, find out how these elements have evolved and how they are classified.

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Operating principle and design of light diodes

LEDs are distinguished from conventional lighting devices by the absence of a filament, a fragile bulb and gas in it. This is a fundamentally different element from them. Scientifically speaking, the glow is created due to the presence of p- and n-type materials in it. The former accumulate a positive charge, and the latter accumulate a negative charge. P-type materials accumulate electrons, while n-type materials form holes (places where electrons are missing). At the moment of appearance on contacts electric charge they rush to the p-n junction, where each electron is injected into the p-type. From the side of the reverse, negative n-type contact, as a result of such movement, a glow occurs. It is caused by the release of photons. However, not all photons emit light visible to the human eye. The force that makes the electrons move is called LED current.

This information is of no use to the average person. It is enough to know that the LED has a durable body and contacts, of which there can be from 2 to 4, and also that each LED has its own nominal voltage required for lighting.

Good to know! The connection is always made in the same order. This means that if you connect “+” to the “-” contact on the element, then there will be no glow - p-type materials simply will not be able to charge, which means there will be no movement towards the transition.

Classification of LEDs by their field of application

Such elements can be indicator and lighting. The former were invented before the latter, and they have long been used in radio electronics. But with the advent of the first lighting LED a real breakthrough in electrical engineering began. The demand for lighting devices of this type is steadily growing. But progress does not stand still - more and more new types are being invented and put into production, which become brighter without consuming more energy. Let's look in more detail at what LEDs are.

Indicator LEDs: a little history

The first such red LED was created in the middle of the twentieth century. Although it had low energy efficiency and emitted a dim glow, the direction turned out to be promising and developments in this area continued. In the 70s, green and yellow elements appeared, and work to improve them did not stop. By the year 90, the strength of their luminous flux reaches 1 Lumen.

The year 1993 was marked by the appearance in Japan of the first blue LED, which was much brighter than its predecessors. This meant that now, by combining three colors (which make up all the shades of the rainbow), you can get any color. In the early 2000s, the luminous flux already reached 100 Lumens. Nowadays, LEDs continue to improve, increasing brightness without increasing power consumption.

Use of LEDs in household and industrial lighting

Now such elements are used in all industries, be it machine or automotive manufacturing, lighting of production workshops, streets or apartments. If we take the latest developments, we can say that even the characteristics of LEDs for flashlights are sometimes not inferior to old 220 V halogen lamps. Let's try to give one example. If we take the characteristics of a 3 W LED, they will be comparable to the data of an incandescent lamp with a consumption of 20-25 W. The result is energy savings of almost 10 times, which, with daily constant use in an apartment, provides a very significant benefit.

What are the benefits of LEDs and are there any disadvantages to them?

A lot can be said about the positive qualities of light diodes. The main ones include:

As for the negative aspects, there are only two of them:

• Work only with constant voltage;
• It follows from the first - the high cost of lamps based on them due to the need to use (an electronic stabilizing unit).

What are the main characteristics of LEDs?

When choosing such elements for a particular purpose, everyone pays attention to their technical data. The main things you should pay attention to when purchasing devices based on them:

• consumption current;
• Rated voltage;
• power consumption;
• color temperature;
• luminous flux strength.

This is what we can see on the marking. In fact, there are much more characteristics. Let's talk about them now.

LED current consumption - what is it?

The LED consumption current is 0.02 A. But this only applies to elements with one crystal. There are also more powerful light diodes, which can contain 2, 3 or even 4 crystals. In this case, the current consumption will increase, a multiple of the number of chips. It is this parameter that dictates the need to select a resistor that is soldered at the input. In this case, the LED resistance prevents the high current from instantly burning the LED element. This may happen due to high mains current.

Rated voltage

The voltage of an LED is directly dependent on its color. This happens due to the difference in the materials used to make them. Let's consider this dependence.

Light diode resistance

The same LED itself can have different resistance. It changes depending on its inclusion in the circuit. In one direction - about 1 kOhm, in the other - several MOhms. But there is a nuance here. LED resistance is nonlinear. This means that it can change depending on the voltage applied to it. The higher the voltage, the lower the resistance will be.

Light output and beam angle

The angle of the luminous flux of LEDs may vary, depending on their shape and material of manufacture. It cannot exceed 120 0. For this reason, if greater dispersion is required, special reflectors and lenses are used. This quality of “directional light” contributes to greatest strength luminous flux, which can reach 300-350 lm for one 3 W LED.

LED lamp power

LED power is a purely individual value. It can vary in the range from 0.5 to 3 W. It can be determined using Ohm's law P = I × U , Where I – current strength, and U – LED voltage.

Power is a fairly important indicator. Especially when it is necessary to calculate what is needed for a particular number of elements.

Colorful temperature

This parameter is similar to other lamps. The temperature spectrum is closest to LED fluorescent lamps. Color temperature is measured in K (Kelvin). The glow can be warm (2700-3000K), neutral (3500-4000K) or cold (5700-7000K). In fact, there are many more shades; the main ones are listed here.

LED element chip size

You won’t be able to measure this parameter yourself when purchasing, and now the dear reader will understand why. The most common sizes are 45x45 mil and 30x30 mil (corresponding to 1 W), 24x40 mil (0.75 W) and 24x24 mil (0.5 W). If we translate into a more familiar measurement system, then 30x30 mil will be equal to 0.762x0.762mm.

There can be many chips (crystals) in one LED. If the element does not have a phosphor layer (RGB - color), then the number of crystals can be counted.

Important! You should not buy very cheap LEDs made in China. They may not only be Low quality, but their characteristics are most often overestimated.

What are SMD LEDs: their characteristics and differences from conventional ones

A clear decoding of this abbreviation looks like Surface Mount Devices, which literally means “surface mounted”. To make it clearer, we can recall that ordinary cylindrical light diodes on legs are recessed into the board and soldered on the other side. In contrast, SMD components are fixed with claws on the same side where they themselves are located. This installation makes it possible to create double-sided printed circuit boards.

Such LEDs are much brighter and more compact than conventional ones and are elements of a new generation. Their dimensions are indicated in the marking. But do not confuse the size of the SMD LED and the crystal (chip) of which there can be many in the component. Let's look at several of these light diodes.

LED SMD2835 parameters: dimensions and characteristics

Many novice craftsmen confuse the markings SMD2835 with SMD3528. On the one hand, they should be the same, because the marking indicates that these LEDs have sizes of 2.8x3.5 mm and 3.5 by 2.8 mm, which are the same thing. However, this is a misconception. The technical characteristics of the SMD2835 LED are much higher, while it has a thickness of only 0.7 mm versus 2 mm for the SMD3528. Let's look at the SMD2835 data with different powers:

As you can understand, the technical characteristics of SMD2835 can be quite varied. It all depends on the quantity and quality of crystals.

5050 LED Specifications: Larger SMD Component

It is quite surprising that, despite its large dimensions, this LED has a lower luminous flux than the previous version - only 18-20 Lm. The reason for this is the small number of crystals - usually there are only two. The most common application of such elements is in LED strips. The density of strips is usually 60 pcs/m, which is total gives about 900 Lm/m. Their advantage in this case is that the tape gives a uniform, calm light. In this case, the angle of its illumination is maximum and equal to 120 0.

Such elements are produced with a white glow (cold or warm shade), single-color (red, blue or green), three-color (RGB), as well as four-color (RGBW).

Characteristics of SMD5730 LEDs

Compared to this component, the previous ones are already considered obsolete. They can already be called super bright LEDs. 3 volts, which feed both 5050 and 2835, produce here up to 50 lm at 0.5 watts. The technical characteristics of the SMD5730 are an order of magnitude higher, which means they need to be considered.

Still, this is not the brightest LED of SMD components. Relatively recently on Russian market elements appeared that literally outshone all the others. We will talk about them now.

Cree LEDs: characteristics and technical data

To date, there are no analogues to Cree products. The characteristics of their super bright LEDs are truly amazing. If previous elements could boast a luminous flux of only 50 Lm from one chip, then, for example, the characteristics of the XHP35 LED from Cree speak of 1300-1500 Lm from one chip. But their power is also greater - it is 13 W.

If we summarize the characteristics of various modifications and models of LEDs of this brand, we can see the following:

The luminous flux strength of the SMD LED "Cree" is called a bin, which is mandatory marked on the packaging. Recently, a lot of counterfeits of this brand have appeared, mostly made in China. When purchasing, it is difficult to distinguish them, but after a month of use, their light dims and they cease to differ from others. At a fairly high cost, such an acquisition will be a rather unpleasant surprise.

We are offering to you short video about this theme:

Checking an LED with a multimeter - how to do it

The simplest and in an accessible way is a “continuity”. Multimeters have a separate switch position specifically for diodes. Having switched the device to the desired position, we touch the LED legs with the probes. If the number “1” appears on the display, you should change the polarity. In this position, the multimeter's buzzer should beep and the LED should light up. If this does not happen, it means it has failed. If the light diode is working properly, but when soldered into the circuit it does not work, there may be two reasons for this - its incorrect location or the failure of the resistor (in modern SMD components it is already built-in, which will become clear during the “dialing” process).

Color coding of light diodes

There is no generally accepted worldwide marking for such products; each manufacturer designates the color as it suits them. In Russia, color coding of LEDs is used, but few people use it, because the list of elements with letter designations is quite impressive and hardly anyone would want to remember it. Most common letter designation, which many consider generally accepted. But such markings are more often found not on powerful elements, but on LED strips.

Decoding the LED strip marking code

In order to understand how the tape is marked, you need to pay attention to the table:

For example, let's take the specific LED CW SMD5050/60 IP68 marking. From it you can understand that this is a white LED strip for surface mounting. The elements installed on it have a size of 5x5mm, in the amount of 60 pcs/m. The degree of protection allows it to work under water for a long time.

What can you make from LEDs with your own hands?

This is a very interesting question. And if you answer it in detail, it will take a lot of time. The most common use of light diodes is the illumination of pendant and suspended ceilings, a work area in the kitchen or even a computer keyboard.

Expert opinion

ES, EM, EO design engineer (power supply, electrical equipment, interior lighting) ASP North-West LLC

“For the operation of such elements, a power stabilizer or controller is required. You can even take it from your old one Chinese garland. Many “craftsmen” write that an ordinary step-down transformer is sufficient, but this is not so. In this case, the diodes will blink.”

Current stabilizer - what function does it perform?

A stabilizer for LEDs is a power source that lowers the voltage and equalizes the current. In other words, it creates conditions for the normal operation of elements. At the same time, it protects against voltage increases or decreases on the LEDs. There are stabilizers that can not only regulate voltage, providing fade out light elements, but also control color or flicker modes. They are called controllers. Similar devices can be seen on garlands. They are also sold in electrical stores for switching with RGB strips. Such controllers are equipped with remote controls.

The design of such a device is not complicated, and if desired, a simple stabilizer can be made with your own hands. To do this, you only need a little knowledge in radio electronics and the ability to hold a soldering iron.

Daytime running lights for a car

The use of light diodes in the automotive industry is quite common. For example, DRLs are manufactured exclusively with their help. But if the car is not equipped with running lights, then purchasing them can hit your pocket. Many car enthusiasts make do with a cheap LED strip, but this is not a very good idea. Especially if the strength of its luminous flux is low. A good solution might be to purchase self-adhesive tape with Cree diodes.

It is quite possible to make DRLs using already broken ones by placing new, powerful diodes inside the old cases.

Important! Daytime running lights are designed specifically to make the car visible during the day and not at night. There is no point in checking how they will shine in the dark. DRLs should be visible in the sun.

Flashing LEDs - what is this for?

A good option for using such elements would be an advertising board. But if it glows statically, it will not attract the attention it deserves. The main task is to assemble and solder the shield - this requires some skills, which are not difficult to acquire. After assembly, you can mount a controller from the same garland. The result is a flashing advertisement that will clearly attract attention.

Color music using light diodes - is it difficult to make?

This job is no longer for beginners. In order to assemble a full-fledged color music with your own hands, you need not only an accurate calculation of the elements, but also knowledge of radio electronics. But still, its simplest version is within the capabilities of everyone.

You can always find a sound sensor in radio electronics stores, and many modern switches have one (light when clapping). If you have an LED strip and a stabilizer, then by running “+” from the power supply to the strip through a similar firecracker, you can achieve the desired result.

Voltage indicator: what to do if it burns out

Modern indicator screwdrivers consist of a light diode and resistors with an insulator. Most often this is an ebonite insert. If the element inside burns out, it can be replaced with a new one. And the craftsman himself will choose the color.

Another option is to make a chain tester. To do this you will need 2 AA batteries, wires and a light diode. Having connected the batteries in series, we solder one of the legs of the element to the positive of the battery. The wires will come from the other leg and from the battery negative. As a result, when shorted, the diode will light up (if the polarity is not reversed).

LED connection diagrams - how to do everything correctly

Such elements can be connected in two ways - in series and in parallel. At the same time, we must not forget that the light diode must be positioned correctly. Otherwise, the scheme will not work. IN ordinary elements with a cylindrical shape, this can be determined as follows: a flag is visible on the cathode (-), it is slightly larger than the anode (+).

How to calculate LED resistance

Calculating the resistance of a light diode is very important. Otherwise, the element will simply burn out, unable to withstand the magnitude of the network current.

This can be done using the formula:

R = (VS – VL) / I, Where

• VS - supply voltage;
• VL – rated voltage for LED;
• I – LED current (usually 0.02 A, which is equal to 20 mA).

Anything is possible if desired. The circuit is quite simple - we use a power supply from a broken mobile phone or any other. The main thing is that it has a rectifier. It is important not to overdo it with the load (with the number of diodes), otherwise there is a risk of burning the power supply. A standard charger will handle 6-12 cells. You can mount a colored backlight for a computer keyboard by taking 2 blue, white, red, green and yellow elements. It turns out quite beautiful.

Helpful information! The voltage supplied by the power supply is 3.7 V. This means that the diodes need to be connected in series-connected pairs in parallel.

Parallel and serial connection: how they are performed

According to the laws of physics and electrical engineering when parallel connection the voltage is distributed evenly across all consumers, remaining unchanged at each of them. With sequential installation, the flow is divided and at each of the consumers it becomes a multiple of their number. In other words, if you take 8 light diodes connected in series, they will work normally on 12 V. If they are connected in parallel, they will burn out.

Connecting 12 V light diodes as the best option

Any LED strip is designed to be connected to a stabilizer that produces 12 or 24 V. Today, a huge range of products is presented on the shelves of Russian stores various manufacturers with these parameters. But still, 12 V tapes and controllers predominate. This voltage is safer for humans, and the cost of such devices is lower. ABOUT self-connection to the 12 V network was mentioned a little higher, but there shouldn’t be any problems with connecting to the controller - they come with a diagram that even a schoolboy can figure out.

Finally

The popularity that light diodes are gaining cannot but rejoice. After all, this makes progress move forward. And who knows, maybe in the near future new LEDs will appear that will have an order of magnitude higher performance than those currently existing.

We hope our article was useful to our dear reader. If you have any questions on the topic, please ask them in the discussions. Our team is always ready to answer them. Write, share your experience, because it can help someone.

Video: how to properly connect an LED

For safety and the ability to continue active activities in the dark, a person needs artificial lighting. Primitive people pushed back the darkness by setting fire to tree branches, then they came up with a torch and a kerosene stove. And only after the invention of the prototype of a modern battery by the French inventor Georges Leclanche in 1866, and the incandescent lamp in 1879 by Thomson Edison, did David Mizell have the opportunity to patent the first electric flashlight in 1896.

Since then, nothing has changed in the electrical circuit of new flashlight samples, until in 1923, Russian scientist Oleg Vladimirovich Losev found a connection between luminescence in silicon carbide and the p-n junction, and in 1990, scientists managed to create an LED with greater luminous efficiency, allowing them to replace a light bulb incandescent The use of LEDs instead of incandescent lamps, due to the low energy consumption of LEDs, has made it possible to repeatedly increase the operating time of flashlights with the same capacity of batteries and accumulators, increase the reliability of flashlights and practically remove all restrictions on the area of ​​their use.

The LED rechargeable flashlight that you see in the photograph came to me for repair with a complaint that the Chinese Lentel GL01 flashlight I bought the other day for $3 does not light, although the battery charge indicator is on.

The external inspection of the lantern made a positive impression. High-quality casting of the case, comfortable handle and switch. The plug rods for connecting to a household network for charging the battery are made retractable, eliminating the need to store the power cord.

Attention! When disassembling and repairing the flashlight, if it is connected to the network, you should be careful. Touching unprotected parts of your body to uninsulated wires and parts may result in electric shock.

How to disassemble the Lentel GL01 LED rechargeable flashlight

Although the flashlight was subject to warranty repair, remembering my experiences during the warranty repair of a faulty electric kettle (the kettle was expensive and the heating element in it burned out, so it was not possible to repair it with my own hands), I decided to do the repair myself.

It was easy to disassemble the lantern. It is enough to turn the ring that secures it by a slight angle counterclockwise. protective glass and pull it back, then unscrew a few screws. It turned out that the ring is fixed to the body using a bayonet connection.

After removing one of the halves of the flashlight body, access to all its components appeared. On the left in the photo you can see a printed circuit board with LEDs, to which a reflector (light reflector) is attached using three screws. In the center there is a black battery with unknown parameters; there is only a marking of the polarity of the terminals. To the right of the battery is the printed circuit board charger and indications. Installed on the right mains plug with retractable rods.

Upon closer examination of the LEDs, it turned out that there were black spots or dots on the emitting surfaces of the crystals of all LEDs. It became clear even without checking the LEDs with a multimeter that the flashlight did not light due to their burnout.

There were also blackened areas on the crystals of two LEDs installed as backlight on the battery charging indication board. In LED lamps and strips, one LED usually fails, and acting as a fuse, it protects the others from burning out. And all nine LEDs in the flashlight failed at the same time. The voltage on the battery could not increase to a value that could damage the LEDs. To find out the reason, I had to draw an electrical circuit diagram.

Finding the cause of the flashlight failure

The electrical circuit of the flashlight consists of two functionally complete parts. The part of the circuit located to the left of switch SA1 acts as a charger. And the part of the circuit shown to the right of the switch provides the glow.

The charger works as follows. The voltage from the 220 V household network is supplied to the current-limiting capacitor C1, then to a bridge rectifier assembled on diodes VD1-VD4. From the rectifier, voltage is supplied to the battery terminals. Resistor R1 serves to discharge the capacitor after removing the flashlight plug from the network. This prevents electric shock from capacitor discharge in the event of your hand accidentally touching two pins of the plug at the same time.

LED HL1, connected in series with current-limiting resistor R2 in the opposite direction with the upper right diode of the bridge, as it turns out, always lights up when the plug is inserted into the network, even if the battery is faulty or disconnected from the circuit.

The operating mode switch SA1 is used to connect separate groups of LEDs to the battery. As you can see from the diagram, it turns out that if the flashlight is connected to the network for charging and the switch slider is in position 3 or 4, then the voltage from the battery charger also goes to the LEDs.

If a person turns on the flashlight and discovers that it does not work, and, not knowing that the switch slide must be set to the “off” position, about which nothing is said in the flashlight’s operating instructions, connects the flashlight to the network for charging, then at the expense If there is a voltage surge at the output of the charger, the LEDs will receive a voltage significantly higher than the calculated one. A current that exceeds the permissible current will flow through the LEDs and they will burn out. As an acid battery ages due to sulfation of the lead plates, the battery charge voltage increases, which also leads to LED burnout.

Another circuit design What surprised me was the parallel connection of seven LEDs, which is unacceptable, since the current-voltage characteristics of even LEDs of the same type are different and therefore the current passing through the LEDs will also not be the same. For this reason, when choosing the value of resistor R4 based on the maximum permissible current flowing through the LEDs, one of them may overload and fail, and this will lead to an overcurrent of parallel-connected LEDs, and they will also burn out.

Rework (modernization) of the electrical circuit of the flashlight

It became obvious that the failure of the flashlight was due to errors made by the developers of its electrical circuit diagram. To repair the lantern and eliminate it repeated breakdown it is necessary to redo it, replacing the LEDs and making minor changes to the electrical circuit.

In order for the battery charge indicator to actually signal that it is charging, the HL1 LED must be connected in series with the battery. To light an LED, a current of several milliamps is required, and the current supplied by the charger should be about 100 mA.

To ensure these conditions, it is enough to disconnect the HL1-R2 chain from the circuit in the places indicated by red crosses and install an additional resistor Rd with a nominal value of 47 Ohms and a power of at least 0.5 W in parallel with it. The charge current flowing through Rd will create a voltage drop of about 3 V across it, which will provide the necessary current for the HL1 indicator to light. At the same time, the connection point between HL1 and Rd must be connected to pin 1 of switch SA1. In this simple way, it will be impossible to supply voltage from the charger to the LEDs EL1-EL10 while charging the battery.

To equalize the magnitude of the currents flowing through the LEDs EL3-EL10, it is necessary to exclude resistor R4 from the circuit and connect a separate resistor with a nominal value of 47-56 Ohms in series with each LED.

Electrical diagram after modification

Minor changes made to the circuit increased the information content of the charge indicator of an inexpensive Chinese LED flashlight and greatly increased its reliability. I hope that LED flashlight manufacturers will make changes to the electrical circuits of their products after reading this article.

After modernization, electrical circuit diagram took the form as in the drawing above. If necessary, use a flashlight long time and you don’t need a high brightness of its glow, you can additionally install a current-limiting resistor R5, thanks to which the operating time of the flashlight without recharging will double.

LED battery flashlight repair

After disassembly, the first thing you need to do is restore the functionality of the flashlight, and then start upgrading it.

Checking the LEDs with a multimeter confirmed that they were faulty. Therefore, all the LEDs had to be desoldered and the holes freed from solder to install new diodes.

Judging by its appearance, the board was equipped with tube LEDs from the HL-508H series with a diameter of 5 mm. LEDs of type HK5H4U from a linear LED lamp with similar technical characteristics were available. They came in handy for repairing the lantern. When soldering LEDs to the board, you must remember to observe polarity; the anode must be connected to the positive terminal of the battery or battery.

After replacing the LEDs, the PCB was connected to the circuit. The brightness of some LEDs was slightly different from others due to the common current-limiting resistor. To eliminate this drawback, it is necessary to remove resistor R4 and replace it with seven resistors, connected in series with each LED.

To select a resistor that ensures optimal operation of the LED, the dependence of the current flowing through the LED on the value of the series-connected resistance was measured at a voltage of 3.6 V, equal to the voltage of the flashlight battery.

Based on the conditions for using the flashlight (in case of interruptions in the power supply to the apartment), high brightness and illumination range were not required, so the resistor was chosen with a nominal value of 56 Ohms. With such a current-limiting resistor, the LED will operate in easy mode, and energy consumption will be economical. If you need to squeeze out maximum brightness from the flashlight, then you should use a resistor, as can be seen from the table, with a nominal value of 33 Ohms and make two modes of operation of the flashlight by turning on another common current-limiting resistor (in the diagram R5) with a nominal value of 5.6 Ohms.

To connect a resistor in series with each LED, you must first prepare the printed circuit board. To do this, you need to cut any one current-carrying path on it, suitable for each LED, and make additional contact pads. The current-carrying paths on the board are protected by a layer of varnish, which must be scraped off with a knife blade to the copper, as in the photograph. Then tin the bare contact pads with solder.

It is better and more convenient to prepare a printed circuit board for mounting resistors and soldering them if the board is mounted on a standard reflector. In this case, the surface of the LED lenses will not be scratched, and it will be more convenient to work.

Connecting the diode board after repair and modernization to the flashlight battery showed that the brightness of all LEDs was sufficient for illumination and the same brightness.

Before I had time to repair the previous lamp, a second one was repaired, with the same fault. On the body of the flashlight there is information about the manufacturer and technical specifications I couldn’t find it, but judging by the manufacturing style and the cause of the breakdown, the manufacturer is the same, Chinese Lentel.

Based on the date on the flashlight body and on the battery, it was possible to establish that the flashlight was already four years old and, according to its owner, the flashlight worked flawlessly. It is obvious that the flashlight lasted a long time thanks to the warning sign “Do not turn on while charging!” on a hinged lid covering a compartment in which a plug is hidden for connecting the flashlight to the mains for charging the battery.

In this flashlight model, the LEDs are included in the circuit according to the rules; a 33 Ohm resistor is installed in series with each one. The resistor value can be easily recognized by color coding using an online calculator. A check with a multimeter showed that all the LEDs were faulty, and the resistors were also broken.

An analysis of the cause of the failure of the LEDs showed that due to sulfation of the acid battery plates, its internal resistance increased and, as a result, its charging voltage increased several times. During charging, the flashlight was turned on, the current through the LEDs and resistors exceeded the limit, which led to their failure. I had to replace not only the LEDs, but also all the resistors. Based on the above-mentioned operating conditions of the flashlight, resistors with a nominal value of 47 Ohms were chosen for replacement. The resistor value for any type of LED can be calculated using an online calculator.

Redesign of the battery charging mode indication circuit

The flashlight has been repaired, and you can begin making changes to the battery charging indication circuit. To do this, it is necessary to cut the track on the printed circuit board of the charger and indication in such a way that the HL1-R2 chain on the LED side is disconnected from the circuit.

The lead-acid AGM battery has been upgraded to deep discharge, and an attempt to charge it with a standard charger was unsuccessful. I had to charge the battery using stationary unit power supply with load current limiting function. A voltage of 30 V was applied to the battery, and at the first moment it consumed only a few mA of current. Over time, the current began to increase and after a few hours increased to 100 mA. After fully charging, the battery was installed in the flashlight.

Charging deeply discharged lead-acid AGM batteries with increased voltage as a result of long-term storage allows you to restore their functionality. I have tested the method on AGM batteries more than a dozen times. New batteries that do not want to be charged from standard chargers, when charging from permanent source at a voltage of 30 V they are restored almost to their original capacity.

The battery was discharged several times by turning on the flashlight in operating mode and charged using a standard charger. The measured charge current was 123 mA, with a voltage at the battery terminals of 6.9 V. Unfortunately, the battery was worn out and was enough to operate the flashlight for 2 hours. That is, the battery capacity was about 0.2 A×hour and for long work The lamp needs to be replaced.

The HL1-R2 chain on the printed circuit board was successfully placed, and it was necessary to cut only one current-carrying path at an angle, as in the photograph. The cutting width must be at least 1 mm. Calculation of the resistor value and testing in practice showed that for stable operation of the battery charging indicator, a 47 Ohm resistor with a power of at least 0.5 W is required.

The photo shows a printed circuit board with a soldered current-limiting resistor. After this modification, the battery charge indicator lights up only if the battery is actually charging.

Modernization of the operating mode switch

To complete the repair and modernization of the lights, it is necessary to resolder the wires at the switch terminals.

In models of flashlights being repaired, a four-position slide-type switch is used to turn on. The middle pin in the photo shown is general. When the switch slide is in the extreme left position, the common terminal is connected to the left terminal of the switch. When moving the switch slide from the extreme left position to one position to the right, its common pin is connected to the second pin and, with further movement of the slide, sequentially to pins 4 and 5.

To the middle common terminal (see photo above) you need to solder a wire coming from the positive terminal of the battery. Thus, it will be possible to connect the battery to a charger or LEDs. To the first pin you can solder a wire coming from the main board with LEDs, to the second you can solder a current-limiting resistor R5 of 5.6 Ohms to be able to switch the flashlight to energy saving mode work. Solder the conductor coming from the charger to the rightmost pin. This will prevent you from turning on the flashlight while the battery is charging.

Repair and modernization
LED rechargeable spotlight "Foton PB-0303"

I received another copy of a series of Chinese-made LED flashlights called the Photon PB-0303 LED spotlight for repair. The flashlight did not respond when the power button was pressed; an attempt to charge the flashlight battery using a charger was unsuccessful.

The flashlight is powerful, expensive, costs about $20. According to the manufacturer, the luminous flux of the flashlight reaches 200 meters, the body is made of impact-resistant ABS plastic, and the kit includes a separate charger and a shoulder strap.

The Photon LED flashlight has good maintainability. To gain access to the electrical circuit, simply unscrew the plastic ring holding the protective glass, rotating the ring counterclockwise when looking at the LEDs.

When repairing any electrical appliances, troubleshooting always starts with the power source. Therefore, the first step was to measure the voltage at the terminals of the acid battery using a multimeter turned on in mode. It was 2.3 V, instead of the required 4.4 V. The battery was completely discharged.

When connecting the charger, the voltage at the battery terminals did not change, it became obvious that the charger was not working. The flashlight was used until the battery was completely discharged, and then it was not used for a long time, which led to a deep discharge of the battery.

It remains to check the serviceability of the LEDs and other elements. To do this, the reflector was removed, for which six screws were unscrewed. On the printed circuit board there were only three LEDs, a chip (chip) in the form of a droplet, a transistor and a diode.

Five wires went from the board and battery into the handle. In order to understand their connection, it was necessary to disassemble it. To do this, use a Phillips screwdriver to unscrew the two screws inside the flashlight, which were located next to the hole into which the wires went.

To detach the flashlight handle from its body, it must be moved away from the mounting screws. This must be done carefully so as not to tear the wires off the board.

As it turned out, there were no radio-electronic elements in the pen. Two white wires were soldered to the terminals of the flashlight on/off button, and the rest to the connector for connecting the charger. A red wire was soldered to pin 1 of the connector (the numbering is conditional), the other end of which was soldered to the positive input of the printed circuit board. A blue-white conductor was soldered to the second contact, the other end of which was soldered to the negative pad of the printed circuit board. A green wire was soldered to pin 3, the second end of which was soldered to the negative terminal of the battery.

Electrical circuit diagram

Having dealt with the wires hidden in the handle, you can draw an electrical circuit diagram of the Photon flashlight.

From the negative terminal of the battery GB1, voltage is supplied to pin 3 of connector X1 and then from its pin 2 through a blue-white conductor it is supplied to the printed circuit board.

Connector X1 is designed in such a way that when the charger plug is not inserted into it, pins 2 and 3 are connected to each other. When the plug is inserted, pins 2 and 3 are disconnected. This ensures automatic disconnection of the electronic part of the circuit from the charger, eliminating the possibility of accidentally turning on the flashlight while charging the battery.

From the positive terminal of battery GB1, voltage is supplied to D1 (microcircuit-chip) and the emitter bipolar transistor type S8550. The CHIP performs only the function of a trigger, allowing a button to turn on or off the glow of EL LEDs (⌀8 mm, glow color - white, power 0.5 W, current consumption 100 mA, voltage drop 3 V.). When you first press the S1 button from the D1 chip, a positive voltage is applied to the base of the transistor Q1, it opens and the supply voltage is supplied to the LEDs EL1-EL3, the flashlight turns on. When you press button S1 again, the transistor closes and the flashlight turns off.

From a technical point of view, such a circuit solution is illiterate, since it increases the cost of the flashlight, reduces its reliability, and in addition, due to the voltage drop at the junction of transistor Q1, up to 20% of the battery capacity is lost. This circuit solution is justified if it is possible to adjust the brightness light beam. In this model, instead of a button, it was enough to install a mechanical switch.

It was surprising that in the circuit, LEDs EL1-EL3 are connected in parallel to the battery like incandescent light bulbs, without current-limiting elements. As a result, when turned on, a current passes through the LEDs, the magnitude of which is limited only internal resistance battery and when it is fully charged, the current may exceed the permissible value for the LEDs, which will lead to their failure.

Checking the functionality of the electrical circuit

To check the serviceability of the microcircuit, transistor and LEDs, a 4.4 V DC voltage was applied from an external power source with a current limiting function, maintaining polarity, directly to the power pins of the printed circuit board. The current limit value was set to 0.5 A.

After pressing the power button, the LEDs lit up. After pressing again, they went out. The LEDs and the microcircuit with the transistor turned out to be serviceable. All that remains is to figure out the battery and charger.

Acid battery recovery

Since the 1.7 A acid battery was completely discharged, and the standard charger was faulty, I decided to charge it from a stationary power supply. When connecting the battery for charging to a power supply with a set voltage of 9 V, the charging current was less than 1 mA. The voltage was increased to 30 V - the current increased to 5 mA, and after an hour at this voltage it was already 44 mA. Next, the voltage was reduced to 12 V, the current dropped to 7 mA. After 12 hours of charging the battery at a voltage of 12 V, the current rose to 100 mA, and the battery was charged with this current for 15 hours.

The temperature of the battery case was within normal limits, which indicated that the charging current was not used to generate heat, but to accumulate energy. After charging the battery and finalizing the circuit, which will be discussed below, tests were carried out. The flashlight with a restored battery illuminated continuously for 16 hours, after which the brightness of the beam began to decrease and therefore it was turned off.

Using the method described above, I had to repeatedly restore the functionality of deeply discharged small-sized acid batteries. As practice has shown, only serviceable batteries that have been forgotten for some time can be restored. Acid batteries that have exhausted their service life cannot be restored.

Charger repair

Measuring the voltage value with a multimeter at the contacts of the output connector of the charger showed its absence.

Judging by the sticker pasted on the adapter body, it was a power supply that produced an unstabilized constant pressure 12 V with a maximum load current of 0.5 A. There were no elements in the electrical circuit that limited the amount of charging current, so the question arose, why was an ordinary power supply used as a charger?

When the adapter was opened, a characteristic smell of burnt electrical wiring appeared, which indicated that the transformer winding had burned out.

A continuity test of the primary winding of the transformer showed that it was broken. After cutting the first layer of tape insulating the primary winding of the transformer, a thermal fuse was discovered, designed for an operating temperature of 130°C. Testing showed that both the primary winding and the thermal fuse were faulty.

Repairing the adapter was not economically feasible, since it was necessary to rewind the primary winding of the transformer and install a new thermal fuse. I replaced it with a similar one that was on hand, with a DC voltage of 9 V. The flexible cord with a connector had to be resoldered from a burnt adapter.

The photo shows a drawing of the electrical circuit of a burnt-out power supply (adapter) of the Photon LED flashlight. The replacement adapter was assembled according to the same scheme, only with an output voltage of 9 V. This voltage is quite sufficient to provide the required battery charging current with a voltage of 4.4 V.

Just for fun, I connected the flashlight to a new power supply and measured the charging current. Its value was 620 mA, and this was at a voltage of 9 V. At a voltage of 12 V, the current was about 900 mA, significantly exceeding the load capacity of the adapter and the recommended battery charging current. For this reason, the primary winding of the transformer burned out due to overheating.

Finalization of the electrical circuit diagram
LED rechargeable flashlight "Photon"

To eliminate circuit violations in order to ensure reliable and long-term work Changes were made to the flashlight circuit and the printed circuit board was modified.

The photo shows the electrical circuit diagram of the converted Photon LED flashlight. Additional installed radio elements are shown in blue. Resistor R2 limits the battery charging current to 120 mA. To increase the charging current, you need to reduce the resistor value. Resistors R3-R5 limit and equalize the current flowing through the LEDs EL1-EL3 when the flashlight is illuminated. The EL4 LED with a series-connected current-limiting resistor R1 is installed to indicate the battery charging process, since the developers of the flashlight did not take care of this.

To install current-limiting resistors on the board, the printed traces were cut, as shown in the photo. The charge current-limiting resistor R2 was soldered at one end to the contact pad, to which the positive wire coming from the charger had previously been soldered, and the soldered wire was soldered to the second terminal of the resistor. An additional wire (yellow in the photo) was soldered to the same contact pad, intended to connect the battery charging indicator.

Resistor R1 and indicator LED EL4 were placed in the flashlight handle, next to the connector for connecting the charger X1. The LED anode pin was soldered to pin 1 of connector X1, and a current-limiting resistor R1 was soldered to the second pin, the cathode of the LED. A wire (yellow in the photo) was soldered to the second terminal of the resistor, connecting it to the terminal of resistor R2, soldered to the printed circuit board. Resistor R2, for ease of installation, could have been placed in the flashlight handle, but since it heats up when charging, I decided to place it in a freer space.

When finalizing the circuit, MLT type resistors with a power of 0.25 W were used, except for R2, which is designed for 0.5 W. The EL4 LED is suitable for any type and color of light.

This photo shows the charging indicator while the battery is charging. Installing an indicator made it possible not only to monitor the battery charging process, but also to monitor the presence of voltage in the network, the health of the power supply and the reliability of its connection.

How to replace a burnt out CHIP

If suddenly a CHIP - a specialized unmarked microcircuit in a Photon LED flashlight, or a similar one assembled according to a similar circuit - fails, then to restore the flashlight's functionality it can be successfully replaced with a mechanical switch.

To do this, you need to remove the D1 chip from the board, and instead of the Q1 transistor switch, connect an ordinary mechanical switch, as shown in the above electrical diagram. The switch on the flashlight body can be installed instead of the S1 button or in any other suitable place.

Repair and alteration of LED flashlight
14Led Smartbuy Colorado

Stopped turning on LED flashlight Smartbuy Colorado, although three AAA batteries were installed new.

The waterproof body was made of anodized aluminum alloy and had a length of 12 cm. The flashlight looked stylish and was easy to use.

How to check batteries for suitability in an LED flashlight

Repair of any electrical device begins with checking the power source, therefore, despite the fact that new batteries were installed in the flashlight, repairs should begin with checking them. In the Smartbuy flashlight, the batteries are installed in a special container, in which they are connected in series using jumpers. In order to gain access to the flashlight batteries, you need to disassemble it by rotating the back cover counterclockwise.

Batteries must be installed in the container, observing the polarity indicated on it. The polarity is also indicated on the container, so it must be inserted into the flashlight body with the side on which the “+” sign is marked.

First of all, it is necessary to visually check all contacts of the container. If there are traces of oxides on them, then the contacts must be cleaned to a shine using sandpaper or scrape off the oxide with a knife blade. To prevent re-oxidation of the contacts, they can be lubricated with a thin layer of any machine oil.

Next you need to check the suitability of the batteries. To do this, touching the probes of a multimeter turned on in DC voltage measurement mode, you need to measure the voltage at the contacts of the container. Three batteries are connected in series and each of them should produce a voltage of 1.5 V, therefore the voltage at the terminals of the container should be 4.5 V.

If the voltage is less than specified, then it is necessary to check the correct polarity of the batteries in the container and measure the voltage of each of them individually. Perhaps only one of them sat down.

If everything is in order with the batteries, then you need to insert the container into the flashlight body, observing the polarity, screw on the cap and check its functionality. In this case, you need to pay attention to the spring in the cover, through which the supply voltage is transmitted to the flashlight body and from it directly to the LEDs. There should be no traces of corrosion on its end.

How to check if the switch is working properly

If the batteries are good and the contacts are clean, but the LEDs do not light, then you need to check the switch.

The Smartbuy Colorado flashlight has a sealed push-button switch with two fixed positions, closing the wire coming from the positive terminal of the battery container. When you press the switch button for the first time, its contacts close, and when you press it again, they open.

Since the flashlight contains batteries, you can also check the switch using a multimeter turned on in voltmeter mode. To do this, you need to rotate it counterclockwise, if you look at the LEDs, unscrew its front part and put it aside. Next, touch the flashlight body with one multimeter probe, and the second one to the contact, which is located deep in the center of the plastic part shown in the photo.

The voltmeter should show a voltage of 4.5 V. If there is no voltage, press the switch button. If it is working properly, then voltage will appear. Otherwise, the switch needs to be repaired.

Checking the health of the LEDs

If the previous search steps failed to detect a fault, then at the next stage you need to check the reliability of the contacts supplying the supply voltage to the board with LEDs, the reliability of their soldering and serviceability.

A printed circuit board with LEDs sealed into it is fixed in the head of the flashlight using a steel spring-loaded ring, through which the supply voltage from the negative terminal of the battery container is simultaneously supplied to the LEDs along the flashlight body. The photo shows the ring from the side it presses against the printed circuit board.

The retaining ring is fixed quite tightly, and it was only possible to remove it using the device shown in the photo. You can bend such a hook from a steel strip with your own hands.

After removing the retaining ring, the printed circuit board with LEDs, which is shown in the photo, was easily removed from the head of the flashlight. The absence of current-limiting resistors immediately caught my eye; all 14 LEDs were connected in parallel and directly to the batteries via a switch. Connecting LEDs directly to a battery is unacceptable, since the amount of current flowing through the LEDs is limited only by the internal resistance of the batteries and can damage the LEDs. IN best case scenario will greatly reduce their service life.

Since all the LEDs in the flashlight were connected in parallel, it was not possible to check them with a multimeter turned on in resistance measurement mode. Therefore, the printed circuit board was supplied with a DC supply voltage from an external source of 4.5 V with a current limit of 200 mA. All LEDs lit up. It became obvious that the problem with the flashlight was poor contact between the printed circuit board and the retaining ring.

Current consumption of LED flashlight

For fun, I measured the current consumption of LEDs from batteries when they were turned on without a current-limiting resistor.

The current was more than 627 mA. The flashlight is equipped with LEDs of type HL-508H, the operating current of which should not exceed 20 mA. 14 LEDs are connected in parallel, therefore, the total current consumption should not exceed 280 mA. Thus, the current flowing through the LEDs more than doubled the rated current.

Such a forced mode of LED operation is unacceptable, as it leads to overheating of the crystal, and as a result, premature failure of the LEDs. An additional disadvantage is that the batteries drain quickly. They will be enough, if the LEDs do not burn out first, for no more than an hour of operation.

The design of the flashlight did not allow soldering current-limiting resistors in series with each LED, so we had to install one common one for all LEDs. The resistor value had to be determined experimentally. To do this, the flashlight was powered by pants batteries and an ammeter was connected to the gap in the positive wire in series with a 5.1 Ohm resistor. The current was about 200 mA. When installing an 8.2 Ohm resistor, the current consumption was 160 mA, which, as tests showed, is quite sufficient for good lighting at a distance of at least 5 meters. The resistor did not get hot to the touch, so Any will do power.

Redesign of the structure

After the study, it became obvious that for reliable and durable operation of the flashlight, it is necessary to additionally install a current-limiting resistor and duplicate the connection of the printed circuit board with the LEDs and the fixing ring with an additional conductor.

If previously it was necessary for the negative bus of the printed circuit board to touch the body of the flashlight, then due to the installation of the resistor, it was necessary to eliminate the contact. To do this, a corner was ground off from the printed circuit board along its entire circumference, from the side of the current-carrying paths, using a needle file.

To prevent the clamping ring from touching the current-carrying tracks when fixing the printed circuit board, four rubber insulators about two millimeters thick were glued onto it with Moment glue, as shown in the photograph. Insulators can be made from any dielectric material, such as plastic or thick cardboard.

The resistor was pre-soldered to the clamping ring, and a piece of wire was soldered to the outermost track of the printed circuit board. An insulating tube was placed over the conductor, and then the wire was soldered to the second terminal of the resistor.

After simply upgrading the flashlight with your own hands, it began to turn on stably and the light beam illuminated objects well at a distance of more than eight meters. Additionally, the battery life has more than tripled, and the reliability of the LEDs has increased many times over.

An analysis of the causes of failure of repaired Chinese LED lights showed that they all failed due to poorly designed electrical circuits. It remains only to find out whether this was done intentionally in order to save on components and shorten the life of the flashlights (so that more people would buy new ones), or as a result of the illiteracy of the developers. I am inclined to the first assumption.

Repair of LED flashlight RED 110

A flashlight with a built-in acid battery was repaired Chinese manufacturer trademark RED. The flashlight had two emitters: one with a beam in the form of a narrow beam and one emitting diffused light.

The photo shows the appearance of the RED 110 flashlight. I immediately liked the flashlight. Convenient body shape, two operating modes, a loop for hanging around the neck, a retractable plug for connecting to the mains for charging. In the flashlight, the diffused light LED section was shining, but the narrow beam was not.

To make the repair, we first unscrewed the black ring securing the reflector, and then unscrewed one self-tapping screw in the hinge area. The case easily separated into two halves. All parts were secured with self-tapping screws and were easily removed.

The charger circuit was made according to the classical scheme. From the network through a current-limiting capacitor with a capacity of 1 μF, voltage was supplied to rectifier bridge from four diodes and then to the battery terminals. The voltage from the battery to the narrow beam LED was supplied through a 460 Ohm current-limiting resistor.

All parts were mounted on a single-sided printed circuit board. The wires were soldered directly to the contact pads. Appearance The printed circuit board is shown in the photograph.

10 side light LEDs were connected in parallel. The supply voltage was supplied to them through a common current-limiting resistor 3R3 (3.3 Ohms), although according to the rules, a separate resistor must be installed for each LED.

During an external inspection of the narrow beam LED, no defects were found. When power was supplied through the flashlight switch from the battery, voltage was present at the LED terminals, and it heated up. It became obvious that the crystal was broken, and this was confirmed by a continuity test with a multimeter. The resistance was 46 ohms for any connection of the probes to the LED terminals. The LED was faulty and needed to be replaced.

For ease of operation, the wires were unsoldered from the LED board. After freeing the LED leads from the solder, it turned out that the LED was tightly held by the entire plane of the reverse side on the printed circuit board. To separate it, we had to fix the board in the desktop temples. Next, place the sharp end of the knife at the junction of the LED and the board and lightly hit the knife handle with a hammer. The LED bounced off.

As usual, there were no markings on the LED housing. Therefore, it was necessary to determine its parameters and select a suitable replacement. Based on the overall dimensions of the LED, the battery voltage and the size of the current-limiting resistor, it was determined that a 1 W LED (current 350 mA, voltage drop 3 V) would be suitable for replacement. From the “Reference Table of Parameters of Popular SMD LEDs,” a white LED6000Am1W-A120 LED was selected for repair.

The printed circuit board on which the LED is installed is made of aluminum and at the same time serves to remove heat from the LED. Therefore, when installing it, it is necessary to ensure good thermal contact due to the tight fit of the rear plane of the LED to the printed circuit board. To do this, before sealing, thermal paste was applied to the contact areas of the surfaces, which is used when installing a radiator on a computer processor.

In order to ensure a tight fit of the LED plane to the board, you must first place it on the plane and slightly bend the leads upward so that they deviate from the plane by 0.5 mm. Next, tin the terminals with solder, apply thermal paste and install the LED on the board. Next, press it to the board (it’s convenient to do this with a screwdriver with the bit removed) and warm up the leads with a soldering iron. Next, remove the screwdriver, press it with a knife at the bend of the lead to the board and heat it with a soldering iron. After the solder has hardened, remove the knife. Due to the spring properties of the leads, the LED will be pressed tightly to the board.

When installing the LED, polarity must be observed. True, in this case, if a mistake is made, it will be possible to swap the voltage supply wires. The LED is soldered and you can check its operation and measure the current consumption and voltage drop.

The current flowing through the LED was 250 mA, the voltage drop was 3.2 V. Hence the power consumption (you need to multiply the current by the voltage) was 0.8 W. It was possible to increase the operating current of the LED by decreasing the resistance to 460 Ohms, but I did not do this, since the brightness of the glow was sufficient. But the LED will operate in a lighter mode, heat up less, and the flashlight’s operating time on a single charge will increase.

Checking the heating of the LED after operating for an hour showed effective heat dissipation. It heated up to a temperature of no more than 45°C. Sea trials showed a sufficient illumination range in the dark, more than 30 meters.

Replacing a lead acid battery in an LED flashlight

A failed acid battery in an LED flashlight can be replaced with either a similar acid battery or a lithium-ion (Li-ion) or nickel-metal hydride (Ni-MH) AA or AAA battery.

In renovated Chinese lanterns Lead-acid AGM batteries of different dimensions without marking with a voltage of 3.6 V were installed. According to calculations, the capacity of these batteries ranges from 1.2 to 2 A×hours.

On sale you can find a similar acid battery from a Russian manufacturer for the 4V 1Ah Delta DT 401 UPS, which has an output voltage of 4 V with a capacity of 1 Ah, costing a couple of dollars. To replace it, simply re-solder the two wires, observing the polarity.

After several years of operation, the Lentel GL01 LED flashlight, the repair of which was described at the beginning of the article, was again brought to me for repair. Diagnostics showed that the acid battery had exhausted its service life.

A Delta DT 401 battery was purchased as a replacement, but it turned out that its geometric dimensions were larger than the faulty one. The standard flashlight battery had dimensions of 21x30x54 mm and was 10 mm higher. I had to modify the flashlight body. So before you buy new battery Make sure it will fit into the flashlight housing.

The stop in the case was removed and a part of the printed circuit board from which a resistor and one LED had previously been soldered off was cut off with a hacksaw.

After modification, the new battery installed well in the flashlight body and now, I hope, will last for many years.

Replacing a lead acid battery
AA or AAA batteries

If it is not possible to purchase a 4V 1Ah Delta DT 401 battery, then it can be successfully replaced with any three AA or AAA size AA or AAA pen-type batteries, which have a voltage of 1.2 V. For this, it is enough connect three batteries in series, observing polarity, using soldering wires. However, such a replacement is not economically feasible, since the cost of three high-quality AA batteries size AA may exceed the cost of purchasing a new LED flashlight.

But where is the guarantee that there are no errors in the electrical circuit of the new LED flashlight, and it will not have to be modified either. Therefore, I think that replacement lead battery in a modified flashlight is advisable, as it will ensure reliable operation of the flashlight for several more years. And it will always be a pleasure to use a flashlight that you have repaired and modernized yourself.

The modern lighting market offers huge selection lighting devices with narrow scattering angles and a long range. These are spotlights general purpose, spotlights for transport, theater stages, studios, construction sites, airfields and many others. Such lighting devices also include powerful battery-powered flashlights.

When choosing the most suitable, modern and effective flashlight, you may immediately become confused, since with all the variety of their designs, types of light sources used, range and beam scattering angle and other parameters, it is difficult to immediately settle on a specific model.

In this article we will try to understand the most important technical features lanterns that influence the correctness of their choice.

The purpose of powerful flashlights

Powerful flashlights are designed for use in difficult conditions where a stable, bright luminous flux is required, the maintenance of which is ensured over a long period of time. Most often they are used in their work by rescue services, employees of the Ministry of Internal Affairs, speleologists and tourists. Typical representatives of this class of lighting devices are search or tactical flashlights. Also powerful are under-barrel flashlights, which are attached under the barrel of a weapon using special fasteners, camping flashlights or those that have a long operating time, headlamps or headlamps, the fastening of which allows you to attach them to your head. Therefore, when choosing a powerful flashlight, you should always pay attention to what purposes it is intended for.

Special conditions in which they are commonly used powerful flashlights, dictate special requirements for their design and lighting characteristics. Namely:

• shock resistance and moisture resistance of the case;
• the presence in lanterns of materials with high thermal conductivity, ensuring effective heat removal from the light source;
• battery capacity, the value of which directly affects the duration of the flashlight and the stability of its luminous flux;
• universal design of the container for installing batteries;
• possibility of adjusting the angle of dispersion of the light flux;
• the reliability of special fastenings, the effectiveness of anti-slip inserts or notches on the handle of the flashlight, the presence of a strap for carrying the flashlight on the shoulder and other nuances.

Body material and handle design

Since it so happens that search lights are the most popular on the market, we will take a look at them as an example.

For the manufacture of the body of modern powerful search lamps, anodized duralumin is often used, lightweight, durable and corrosion-resistant, on the outer surface of which either anti-slip polyurethane coating is applied, resistant to scratches and impacts, or longitudinal, transverse and diagonal notches. The body of such flashlights is mostly made in the form of a tube that simultaneously performs two functions - a handle and a container for batteries. But there are flashlights with a remote handle. Examples of cases and handles can be seen in the images below.

The images also clearly show the radiator fins, which increase the efficiency of heat removal from the light source. The ribs are made by turning the body metal mass closer to the optical part of the flashlight.

Waterproof

Flashlights have different degrees of protection against foreign objects and moisture getting inside their housing. Since all flashlights have minimal protection capable of trapping dust particles, but are not able to work when they are exposed to drops and splashes of water for a long time, they can be divided into two groups: non-moisture-resistant and moisture-resistant flashlights. According to the classification system for degrees of protection (IP - Ingress Protection Rating), non-moisture resistant ones can be assigned the value IP50, that is, dust-proof and moisture-permeable. Housings for moisture-resistant flashlights are usually produced with the ability to immerse all flashlights under water. Therefore, their degree of protection starts from IP67 and ends with IP69. Sometimes the number indicating the penetration of foreign objects is omitted and the letter “X” is placed instead of the first number (IPХ7 - IPХ9).

Let's decipher the meaning of numbers 7 - 9. Number 7 indicates the possibility of briefly immersing the flashlight to a depth of up to 1 meter. The number 8 indicates the possibility of long-term immersion of the flashlight to a depth of more than 1 meter. The number 9 indicates the possibility of long-term immersion of the flashlight to a very great depth, where there is high fluid pressure.

Sources of light

The light source is perhaps the most important element that characterizes the consumer and operational parameters of flashlights. Conventional incandescent lamps are becoming a thing of the past and are no longer used in modern powerful flashlights. Modern high-power flashlights use halogen incandescent lamps, xenon discharge lamps (HID) and light-emitting diodes (LED) as light sources.

Halogen lamps

This is an improved type of incandescent lamps and we can only talk about their advantages in comparison with traditional options. Filling the bulb of an incandescent lamp with halogen additives made it possible to increase its luminous efficiency at the same power and extend its service life by half (up to 2000 hours) by reducing tungsten burnout.

The lamps have an average light output of 22 Lm/W. This is almost twice as high as a conventional incandescent lamp, but it is still very low considering that the lamp must be operated in a portable flashlight and the energy source has a limited resource. Lamps are very sensitive to frequent switching on, during which they mostly burn out.

Like conventional incandescent lamps, they are becoming a thing of the past, because it is difficult for them to compete with durable and energy-efficient LED and xenon light sources.

Xenon lamps

A characteristic feature of xenon lamps is that the electrical discharge of the lamp occurs in the inert gas xenon, at high pressure and high current densities. For this reason, lamps have very high brightness and the visible emission spectrum is close to sunlight with a color temperature of 6100 - 6300 K.

Xenon lamps have a high ignition voltage and therefore require the use of special ignition devices. After ignition, the lamps light up within approximately 15 seconds.

Xenon lamps are very sensitive to changes in supply voltage. When the supply voltage changes by ±5%, the lamp power changes by ±20%. For this reason, when using lamps of this type, it is necessary to use stabilizing devices that maintain the voltage at the same level as the battery discharges.

The light output of a xenon lamp ranges from 80 to 100 Lm/W. Xenon discharge has the highest brightness. According to theoretical estimates, it maximum brightness can reach 2000 MKd/m².

The bright, powerful luminous flux of the daytime spectrum allows you to evenly illuminate a large area, which makes such lanterns an indispensable tool for search work in accident sites, in conditions of heavy dust and gas contamination in mines, deep wells and caves. The light of a xenon flashlight is noticeable even during the day at a great distance, which is very important when rescue work in the mountains and taiga.

This type of light source confidently displaces incandescent lamps and gas-discharge lamps from modern models lanterns This fact is easily explained by the following advantages of LEDs:

• the LED, unlike a xenon lamp, is inertia-free and when a supply voltage is applied to it, it instantly reaches the nominal glow mode, just like a halogen lamp;
• the heating temperature of the LED is much lower than the heating temperature of halogen and xenon lamps;
• Since when the LED lights up, less energy is spent on heating, LEDs today have the highest efficiency - up to 45%. By comparison, a halogen lamp has an efficiency of about 5%, a xenon lamp - up to 30%;
• The maximum luminous efficiency of LEDs used in industrial production is 120 Lm/W. The average luminous efficiency of LEDs used in battery-powered flashlights is 80 - 95 Lm/W, that is, comparable to the luminous efficiency of xenon lamps.

Light distribution

Powerful flashlights can be classified both by the type of light source and by the direction of the light flux. Speaking about the direction of the light flux, we can distinguish two types of powerful flashlights:

• spotlights. The beam of light from such lanterns has a wide front and is capable of illuminating objects located at a fairly large distance, more than five hundred meters;
• long-range flashlights. The beam of light from such lanterns has a very narrow directionality so that one bright spot is projected on the illuminated object, but the range of such a beam reaches one and a half kilometers. For information: the range of the flashlight is determined by the distance at which the illumination level is equivalent to the light intensity of the full moon, which is taken equal to 0.25 lux and is optimal for safe movement.

Spotlights are most effective at short and medium distances up to five hundred meters. Their the most important characteristic It is not the range of action, but the brightness of the light flux over the maximum area without deep shadow. This is ensured thanks to the special design of the reflectors. Spotlights are an ideal option for outdoor activities, hunting and fishing.

Long-range flashlights have a completely different purpose. Long-range flashlights are used by speleologists, searchers, and miners.

Long-range flashlights usually include flashlights with a lighting range of 500 meters or more. This is also ensured by the design of reflectors and optics, which allow the light beam to be focused. What is important here is not the scattering of light, but its concentration at one point, the formation of a bright light spot.

Very often, the functions of spotlights and long-range flashlights are combined in one flashlight. Structurally, such lanterns have a movable (in the axial direction) diffuser and a lens installed at the outlet. By adjusting them, they achieve the creation of a light spot of the required diameter. When adjusted, the angle of light redistribution and the focal distance between the lamp (LED) and the illuminated object change.

Rechargeable batteries

Powerful search-type LED flashlights are powered mainly by two types of replaceable batteries, these are 26650 and 18650, with an output voltage of 3.7 V. Such batteries are produced by many companies and have different prices, declared capacity values, discharge and charge times. Batteries of these types are widely used not only for powering flashlights, but also, for example, for making laptop batteries. Therefore, there should not be any difficulties in purchasing such batteries.

IN different models Lanterns come with different numbers of batteries. Basically these are 2, 3 elements. There are a large number of flashlight models with a universal container designed to install 1, 2 or 3 elements by adding it to the handle special insert supplied with the flashlight.

Since 18650 and 26650 batteries have the same length, 65 mm, some flashlight models can use batteries of both types. To prevent the 18650 elements from “dangling” inside the container, a plastic adapter sleeve is included with the flashlight.

In small lanterns it is possible to install 1 element. It happens that instead of 1 18650 element, 2 CR123A elements are used.

More powerful battery-powered LED flashlights can be equipped with D-type cells with a capacity of 10,000 mAh and a voltage of 1.2 V.

In general, when choosing a flashlight, you should definitely be interested in what batteries are used in them, and what they can be replaced with. To assess the possibility of such a replacement, see the tables of standard sizes of galvanic cells.

If you decide on a search flashlight model, remember that for its successful, reliable and long-term operation you need quality batteries. I think that if you are going to spend a significant amount of money on a flashlight, you should not skimp on its most important element.

In the case of flashlights that work with a xenon lamp, from the point of view of choosing a power element, everything is much simpler. All flashlights have their own batteries, which are supplied with the flashlight. Therefore, when choosing a flashlight, you don’t need to think about anything. However, if you look at this from an operational point of view, then over time there may be problems with replacing them.

Although there are exceptions. For example, the flashlight shown in the photo below is powered by four 18650 batteries.

Operating modes

The operating modes of flashlights with a xenon lamp, due to the inertia of turning on the lamp and the limited number of its on-off cycles, as a rule, have three operating modes, namely these are the modes in which the lamp operates at different powers. Each lantern has an operating mode at minimum power, at which the lamp glows stably, an operating mode at rated power, and a forced mode, at which maximum brightness is created. When operating in the latter mode, the battery capacity is naturally consumed very quickly.

A powerful LED rechargeable flashlight, in addition to the listed operating modes of xenon flashlights, has two additional operating modes, these are:

• stroboscopic mode. This mode is intended for self-defense from an attacking enemy, by disorienting him in space with very bright and frequent light pulses;
• SOS mode or beacon to attract the attention of strangers to you.

To summarize, we can conclude that powerful flashlights with halogen incandescent lamps have faded into the background. The leadership is shared by flashlights with xenon lamps and flashlights with LEDs. However, LED high-power flashlights have characteristics comparable to flashlights equipped with xenon lamps, and therefore are increasingly used.

And finally, we invite you to watch a video review of two portable, powerful rechargeable LED flashlights made in China and Germany.

Suitable different power. The luminous efficiency of the device should not exceed 80 lm. You should also pay attention to the driver. Typically it is installed with an output capacitor. Some models have an amplifier. On average, their current consumption is 3 A.

If we consider sensitive modifications, they have a surge protection system installed. In order to understand the issue in more detail, it is necessary to consider specific models.

Circuits with capacitive capacitors

LED flashlight circuits with capacitive capacitors include wave filters. In this case, triggers are used on a semiconductor basis. As a rule, their output voltage parameter does not exceed 20 V. Converters are used to reduce sensitivity. Drivers for models are installed with different throughputs. If we consider a 30 V LED, then it has a transceiver.

Using snubber capacitors

The LED circuit with a damping capacitor includes contact filters. In total, the models have two converters. The driver is connected to the LED through a winding. Some modifications have a compact transceiver. Most often it is used with an amplifier.

Characteristics of LED marked 530

These are universal for flashlights. The characteristics of the devices indicate a high conductivity coefficient. LEDs are produced for 20 and 25 V. If we consider the first option, the luminous efficiency of the device is on average 60 lm. The color rendering coefficient in this case depends on the conductivity of the transceiver. For many models, the amplifier is used without a converter.

The current consumption of LEDs does not exceed 2.5 A. The turn-on time for models of this type is about 6 ms. If we consider 25 V LEDs, then they only use a pulse transceiver. Many models have one amplifier. The driver is connected using a converter. The luminous flux parameter is around 65 lm. The turn-on time for LEDs of this type is 7 ms.

LED 640 (LEDs for flashlights): characteristics, photos

The LED circuit of this series includes a phase-type converter. Filters are used to increase sensitivity. Amplifiers are most often used on a magnetic basis. The luminous efficiency parameter in the devices is 65 lm. It is also important to note that the current consumption does not exceed 4.2 A. The frequency deviation averages 4 Hz.

The service life of this type of LED is three years. The disadvantages of the devices include the low current conductivity of the drivers. Their brightness indicator is extremely low. Light output, as a rule, does not exceed 5%. These 6 volt flashlight LEDs work well.

Using LED 765

The 12V unit uses the specified flashlight LEDs. The 2014 specifications indicate an increased level of current consumption. this modification is equal to 45 lm. It is also important to note that the model is suitable for switching amplifiers. The driver in the device is used at 6.5 microns. Phase interference with these LEDs is not a problem.

Luminous efficiency averages 70 lm. The service life of the device does not exceed four years. The color rendering coefficient is 80%. The model is perfect for flashlights with regulators. In this case, the devices are connected via a contact adapter.

LED 840 circuit

These are compact and universal LEDs for flashlights. The characteristics of the model primarily indicate a high dispersion rate. Its pulsation coefficient reaches a maximum of 80%. The device turn-on time is 5 ms. According to experts, the model is excellent for 12 V flashlights. The amplifier in the device is of the absorbing type.

In total, the model has two drivers. The LED trigger is used with an adapter. To solve problems with heat loss, a capacitor is used as standard. The luminous efficiency of the presented model is 67 lm. The conductivity indicator does not exceed 10 microns. In this case, the current consumption is 0.3. The minimum permissible LED temperature is only -10 degrees. The model does not have an overheating protection system.

Characteristics of LED 827

Models with are suitable for the indicated LEDs for flashlights. The characteristics of the device indicate the presence of high-quality wired transceivers. The model has amplifiers installed open type. The device uses two capacitors in total. They do an excellent job of minimizing heat loss. The minimum permissible LED temperature is -15 degrees.

They are not suitable for 15V flashlights. The protection system in the device is used with filters. The model has a driver for 4.5 microns. The current consumption is no more than 4 A. The LED turn-on time is on average 6 ms. The pulsation coefficient of the model is 85%. Luminous efficiency, as a rule, does not exceed 50 lm.

LED 830

These flashlight LEDs are perfect for 10V devices. Their characteristics are quite good. The turn-on time is 5 ms, the luminous efficiency is 65 lm, and the current consumption is 3.3 A. The model uses a phase-type converter. According to experts, the model is not suitable for 15 V flashlights.

There is no transceiver in the indicated LED. The driver itself is installed with a conductivity of 4.5 microns. Problems with current rectification are solved thanks to capacitors. The pulsation coefficient of the model reaches a maximum of 90%. The service life of the presented device is three years. The minimum permissible LED temperature does not exceed -20 degrees.

Characteristics of LED series LB

The specified LED is suitable for 15 V flashlights. The characteristics of the model indicate an increased color rendering coefficient. The output voltage of the model is 15 V. The filter in the device is of the wave type. The driver in this case is connected via a conductor. The LED transceiver is used with an adapter. The capacitor is installed in an open type. The model has two triggers in total. In this case, the energy consumption is 2.5 A.

The luminous flux of the device reaches a maximum of 65 lm. The pulsation coefficient of the model is insignificant. Also, the disadvantages can be attributed to the low level of the minimum permissible temperature. A Chinese LED flashlight turns on in 4 ms. The model rarely has problems with current rectification. This model is not suitable for 10V flashlights. The LED does not have an overheating protection system. The frequency deviation of the model is 5 Hz. These Cree flashlight LEDs work great.

daylight

These LEDs for flashlights are produced with high-quality pulse-type amplifiers. In total, the model has two capacitors. The transceiver is standard wired type. It is also important to note that the maximum frequency deviation is 4 Hz. The current consumption of the LED does not exceed 3 A. The luminous flux of the device is 70 lm. The light output of the model is insignificant.

According to experts, the model is excellent for 12 V flashlights. The driver is directly connected via an adapter. On average, the turn-on time is 6 ms. The service life of the presented model is 5 years. The minimum permissible LED temperature is -15 degrees.

TB series (warm white light)

These are simple and inexpensive LEDs for flashlights. The characteristics of the device indicate that the color rendering coefficient of the model is low. It is also important to note that output voltage equals 8 V. The service life of the LED is three years. The transceiver of the modification is used with high sensitivity. In total, the model has two capacitors. According to experts, the device is not suitable for 10 V flashlights. The current consumption of the model is 2 A. The LED luminous flux reaches a maximum of 65 lm.

Problems with negative modulation are rare. The disadvantages include only a small conductivity parameter. Filters in the device are used only of the open type. The maximum frequency deviation of the LED reaches 5 Hz. To reduce the sensitivity, a trigger is used on the capacitor. The pulsation coefficient of the model is insignificant. To install the LED, a wire adapter is required.

Features of LED models of the LHB series (cold white light)

These LEDs have good characteristics. First of all, it is important to note that the color rendering coefficient is 80%. In this case, the service life is three years. The direct output voltage is 12 V. The turn-on time is 5 ms. In this case, the amplifier is used with an adapter. According to experts, problems with heat loss are rare. The model's capacitors are of the pass-through type.