Separately how to connect the light and LED strip. Choosing LED strip: types, power supply, technical characteristics. How LED strip works

LED strip - power is connected. (It appears that the blue wire is soldered to the plus. This is not the case. The brown wire is soldered to the plus, and the “plus” is actually a pair of scissors.)

LED strip is used in most cases for decorative lighting, as was shown in the article about. It can also be used for local lighting, for example, small work spaces (kitchen, computer desk).

Design and circuit of LED strip

Briefly, what is an LED strip and how it works. As an example – Gauss Led, 5 meters, power supply 12 V, 4.8 W/m, 60 LEDs 3528 per meter, without moisture protection.

I’ll say right away that the tape can have a different design, circuit, supply voltage, number of LEDs per meter, their power, color, etc. The LED strip that I discuss in this article is perhaps the simplest and cheapest.

Such a tape actually consists of these pieces:

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The photo shows two such pieces, each containing 3 LEDs and 1 limiting resistor. The tape is sold in reels in long pieces, usually 5 meters long. The design of the LED strip is such that it can be used, but the pieces are much shorter - usually 5 centimeters. In duralight – a meter or 2!

The diagram of an elementary (minimum possible) piece of diode strip looks like this:

LED strip - diagram of an elementary segment. It can't be less.

The diagram of the entire LED strip looks like this:

If the length of the tape is 5 m, and the length of the minimum segment is 5 cm, then it is easy to guess that the number of pieces in the tape will be 100 pieces.

Power (brightness) of the tape

It is clear that brightness depends on the density of LEDs per linear meter, and on the power of these diodes.

Nowadays, strips with two types of LEDs are mainly on sale - 3528 (less powerful, example in the article) and 5050 (more powerful). At a glance, it is very easy to distinguish them - 5050 is larger and has a square shape.

For information, SMD LEDs, which are used in LED strips. Their parameters are summarized in the table. The first two digits and the second two digits in the name are the length and width, respectively. And size indirectly indicates power.

Connecting LED strip

The LED strip turned on in laboratory conditions looks like this:

2 pieces of diode strip - power is applied. +/- polarity matters.

When connecting power to the LED strip, it plays a role power polarity, as in the entire semiconductor world. Unlike incandescent lamps and heating elements, where polarity does not matter. However, if you enable LED strip in the wrong polarity, nothing bad will happen - it just won’t burn. You can safely check the correct connection by swapping the power wires.

If you need to cut a piece of tape from a whole piece, it have to solder, that is, solder the supply wires to the contact pads, which are located at the ends of each elementary piece. There are also scissors drawn there. The wire for connecting the LED strip should be used thin, with a cross-section of no more than 0.5 mm2, as shown in the first photo of the article. Before soldering, clean and tin the contact pads. Use a soldering iron with a power of no more than 40 W, preferably 25 W.

And remember, the soldering point is the most unreliable place in the entire structure; it must be protected from mechanical overloads!

For some types of tapes, there are special connectors on sale that fit onto the tape, without the need to use soldering.

The photo below shows an example of how to connect an LED strip through a connector:

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Connectors for connecting Jazzway LED strip

Connecting the power supply for the LED strip

As a bonus, this is how to practically connect an LED strip. There are several subtleties here (I don’t like the word “nuances”).

Power for the LED strip is provided by a power supply. For this case, two parameters are important: voltage (usually 12 or 24 Volts) and power (depending on the length of the strip and the power of the LEDs). I’ll tell you more about this below.

Just in case, here's a photo of the power supply:

Power supply for LED strip.

This unit has a power of 60 watts, with a reserve of two pieces of 24 watts each.

It is best to buy such power supplies on AliExpress; compare prices there and in a nearby store. The only negative is that you have to wait 30-40 days, so this option is for the thrifty and prudent).

Here are some links as an example. The power supply unit and the length of the tape are selected with a reserve.

1. Power supply for tape 12 V 5A 60 W. For a tape of 4.8 W/m it is enough for 10 meters, for 9.6 W/m – for 5 meters (1 reel).

2. Power supply for tape 12 V 10A 120 W. For a tape of 4.8 W/m it is enough for 20 meters, for 9.6 W/m – for 10 meters.

3. Power supply for tape 12 V 20A 240 W. For a tape of 4.8 W/m it is enough for 40 meters, for 9.6 W/m – for 20 meters.

Since we are talking about such long lengths, an important note. If the length of the connected section of the LED strip is 10 m or more, and you can look around this entire section, you will notice that the brightness decreases towards the end of the section. To eliminate this effect, you need to connect such a long piece in one more place. For example, at the end, or in the middle.

When connecting the LED strip to the power supply, the main thing is to observe the polarity. According to the contacts - phase, zero, ground - this is the input of the power supply unit. The -V and +V contacts are the output voltage of 12 V. To the right is a trimming resistor, which can be used to adjust the output voltage from approximately 11 to 13 Volts.

As the supply voltage increases, the temperature of the LEDs increases, and the service life of the LED strip decreases sharply (the brightness decreases over time).

The voltage of the tape is usually written on the packaging; based on this, the power supply is selected - 12 or 24 V.

LED strip power should be no more than 75% power power supply. In other words, there must be a power reserve of at least 25%. The power of a given piece (segment) of tape is easy to find out. It is necessary to multiply the power per linear meter (Watts per meter) by the length of the tape.

For example, the linear power of the Gauss tape given as an example below is 4.8 W/m. This means that the power of a 5m piece will be 24 W. And the power supply must be selected with a power of 35...50W.

If the power of the unit is comparable to the power of the load, the unit may overheat, especially if installed in a tight space under the ceiling. And if the power of the power source is less than the power of the tape, the tape simply will not be able to turn on, and will blink, trying to turn on. In other words, the power supply simply will not be able to start, the internal protection will be triggered.

And also on connecting the power supply. Never supply power to it through an illuminated switch.! Otherwise, there will be something similar, described in the article about how. Here the power supply will try to start, and a 1 MOhm resistor will not get rid of it. Even 100 kOhm may not be enough.

Naturally, the contacts must be carefully protected from accidental contact. Below are photos of how to simply protect open contacts from touching using a piece of cable duct of the selected width.

There are power supplies for LED strips with special protective caps, but they are of little help, and electrical safety is still low. You can, of course, wrap it all up with electrical tape... but it won’t look very good.

There are other power supplies, in plastic cases and waterproof. Perhaps they are more preferable in residential areas, in places where a child/cat/dog can get into.

Instructions for the LED strip

For those who need it, I’ll post what was included with the tape.

Individual objects in the room are also gaining increasing popularity: mirrors, shelves in the closet, beds. For this lighting option, a special tape is used, which can be single-color or multi-color (RGB). If you don’t know how to connect an LED strip to 220 volts with your own hands, then we will provide step-by-step instructions with diagrams, photos and video tutorials.

Single color

Connecting a single-color LED strip is not difficult. All you need is to purchase the components of the backlight, cut the required length of LED strip, solder it to the power supply and insulate the exposed contacts. Now we will consider in detail each of the connection stages.

Selecting a connection diagram

To independently connect an LED strip to a 220 volt network, you must first select a diagram for connecting all the elements. If you decide to make lighting using no more than 5 meters of product, then just connect the strip to a 220 x 12 V power supply, and connect the power supply to your home network via a cord with a plug.

However, it often happens that you need to connect more than 5 meters of LED strip - 10, 15 or even 20 meters. In this case, it is prohibited to connect all segments sequentially, because the first 5-meter section will overheat and at the same time the voltage in subsequent sections will drop significantly. Such a connection will shorten the life of the LED backlight. We examined all the most popular ones in detail in the corresponding article. For example, let's provide them again.

Consistently (allowed if you need to add a small segment):

Parallel:

With two power supplies (if the tape is long):

We draw your attention to the fact that you can connect the LED strip through a switch or, which is very convenient when creating additional lighting in the kitchen or another room. In this case, the light switch is connected in front of the power supply in a phase break, as shown in the diagram below:

The dimmer must be connected after the power supply, as shown in this example:

We’ve sorted out the diagrams for connecting LEDs to a 220v network, now let’s move on to the process of connecting the circuit elements.

Connecting components

In the simplest example, we have a 220/12v power supply and 5 meters of single-color LED strip. To connect all elements to 220 volts, you need to perform the following steps:

That's all step by step instructions for dummies on how to connect an LED strip to a power supply and network with your own hands. It should be noted that you can connect the product even without soldering, using special connectors, as in the photo below.

The disadvantage of such adapters is that over time the contact will deteriorate, which cannot be said about a more reliable one. You can see how to connect an LED strip using connectors and soldering in the video below:

Visual instructions for connecting contacts

Multicolor

If you want to connect an RGB color strip at home, the connection technology will not change much. A controller will be added to the circuit with a multicolor device, without which the circuit will not be able to work, and the output will also have 4 contacts instead of two. We also reviewed them and bring them to your attention once again.

Standard way:

Parallel connection:

Amplifier usage:

Otherwise, the connection instructions are similar to the previous one - the wires are soldered, the exposed contacts are insulated, after which the correct connection of all circuit elements is checked! You can clearly see how to connect a multi-colored RGB strip to the network with your own hands in the video below:

Instructions for connecting multi-color tape

That's all we wanted to tell you about how to connect an LED strip to 220 volts with your own hands. As you can see, the instructions for connecting a multi-color and a single-color model are not very different, the main thing is to correctly connect the wires by color. If you have any questions, you can ask them using the form!

If you have become the owner of an LED strip, power supply and all installation accessories and you are faced with the question, then I ask you to pay attention to this article. In it I will answer the main questions that arise when installing and connecting diode strips.

LED strips are known for their small size and increased flexibility. The efficient LEDs are mounted on a 10 mm wide circuit board and range in length from 3 to 20 meters. Flexible LED strips have many features that make them easy to use in various situations:

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Is it possible to bend LED strip?

So. How to connect an LED strip?
The first and one of the most important steps is to check the LED strip before installation.
Checking the tape before installation.

ATTENTION! Check the tape before installation! If the tape loses its presentation, as a rule, it cannot be returned or exchanged and you will never get your money back.
1) Remove the spool of tape from its packaging.
2) Carefully unwind the tape and make sure there is no mechanical damage
3) Make sure that the output voltage and power of the power supply matches the supply voltage and power of the LED strip.
4) Connect the tape to the output of the power supply, observing the polarity.
5) Turn on the power. ATTENTION! When turning on an LED strip wound on a reel for more than 30 seconds, it will lead to premature failure of the LEDs. Even if the tape didn't burn out right away.
6) Check the uniformity of the LEDs.
7) Make sure that all the LEDs are lit and the shades of the glow of the tapes of different reels match.
8) Disconnect the source from the network after checking.

How to properly connect an LED strip?

In order to correctly connect the LED strip, you must follow the following rules:
LED strip connection methods
STRICTLY PROHIBITED!
1) LED strips with a power of more than 14.5 W/m should not be connected in series with a length of more than 5 m. This leads to significant voltage drops, uneven lighting, an increase in current through the conductive paths, overheating of the strip and its failure.
2) Installation of the tape on heated surfaces with temperatures above +40 ° (as well as operation at temperatures environment above +45° and near heat sources: heating systems, power supplies, lamps, fixtures.
3) Mechanical impact on the LEDs, pressing or pressure on their surface, as well as rubbing the LEDs. These actions disrupt the structure and lead to failure of the LEDs.
4) Exceeding the specified supply voltage of the tape. Power supply with increased voltage leads to overheating of the tape and its failure.

LED strip connection methods.

Simple scheme how to connect LED strip. Parallel connection of LED strips best option for constructing light lines from LED strip more than 5 m long.

How to connect RGB LED strip?

Below is a detailed illustrated diagram of how to connect an LED.

LED strip 12 volts how to connect?

12 volt LED strips, like any other LED strip, except , should be connected according to the following diagram.

How to connect several LED strips to one power source?

Often you need to connect several LED strips. To do this, you will need to lay parallel wires from the power source to each individual section of LED strips with a total length of 5 m.

How to install and connect LED strip?

1) First you need to prepare the surface of the ceiling or wall for installing the tape. The base must be dry and pre-degreased. It is better to use a degreaser. The LED strip is most reliably glued to the surface of plastics and metals. It is very important that the base is level and smooth, without depressions, protrusions or dirt.

2) Cut the LED strip into pieces of the required length.

3) Peel off the backing from the base of the 3M tape

4) Securely fix the LED strip on the plane.

5) Connect the diode strip according to one of the diagrams given in this article

How to connect an LED strip without soldering?

The LED strip does not always have to be soldered; it can be easily connected using special connectors. When purchasing a connector, make sure that the width of the connector matches the width of your LED strip. How to connect an LED strip without soldering? You just need to follow the instructions below.
Attention: Connector fixation is not always reliable.


The controversial question is how to properly connect the LED strip, using connectors or more reliable soldering. In my opinion, in this matter you need to start from straightness of hands.

How to solder LED strip?

1. Strip the ends of the wire to 3-5 mm and then twist.
2. Apply a drop of alcohol flux to the twist and tin it using a soldering iron.
3. The connection of the wires is carried out in accordance with the color marking, and the loop conductors are brought to the contact pad on the tape.
4. It is recommended to seal the solder area with silicone sealants.

Is it possible to cut LED strip?

Cutting LED strips is very easy thanks to the cutting lines along the strips. At each cutting point there is a black line with copper solder pads located on each side. Copper soldering pads are divided so that each piece of LED strip can be soldered after cutting. This allows you to connect LED strips together or connect strips elsewhere in your home.

You can cut the diode strip in the designated places, between the soldering pads. Use scissors for cutting. When installing the diode strip on metal and other conductive surfaces, in order to prevent a short circuit, insulate the strip from the surface.

Is it possible to glue LED strip?

It is advisable to apply the tape to smooth, grease-free surfaces. It is advisable to stick the tape the first time; repeated gluing of the tape does not allow for reliable fixation. The LED strips are backed with 3M adhesive for easy mounting options. The LED strip has a peelable backing that exposes the 3M adhesive for easy installation.

Fixing an LED strip with an adhesive base is as easy as shelling pears, but sometimes stronger fixation is required. As with most adhesives, it does not adhere well to some surfaces and may need strengthening over time. In these situations, use additional devices for fixing:

• Extra Adhesive Tape- 3M tape, which you additionally glue to the surface in front of the strip to double the gluing.
• LED Strip Mounting clips— Mounting brackets for LED strips. See photo.

Installing LED strip in aluminum profile is another great option for those who want a professional finish. Aluminum profiles for LED strips are the best solution for installation. LED strips adhere perfectly to the bottom of the profile, and the light diffuser creates additional diffusion of light and creates the effect of a uniform light strip, without pronounced points.

MANDATORY REQUIREMENTS AND RECOMMENDATIONS
Observe the operating conditions:
1. The tape must be powered from a stabilized DC voltage source.
2. The tape is intended for indoor use.
3. Ambient temperature -20… +45 “C. Relative air humidity is no more than 80% at +25 “C.
4. The absence of vapors and aggressive impurities (acids, alkalis, etc.) in the air.
5. When connecting a tape with a total length of more than 5 meters, use a parallel connection of the tapes.
6. Check the connection polarity, reliability and correctness of connections before turning on.
7. To extend the service life of the tape, install it on an additional heat sink, for example, an aluminum profile.
8. When installing the tape on metal and other conductive surfaces, in order to prevent a short circuit, insulate the tape from the surface.
9. Do not subject the tape or its components to mechanical stress.
10. Do not damage the conductive paths of the tape.
11. The minimum bending radius of the tape is 3 cm.
12. Avoid moisture and condensation on the tape.
13. Before installing the tapes, visually check the glow and select the BIN. When installing multiple tapes next to each other, it is recommended to use tapes with the same BIN value.
14. You can cut the tape in the designated places, between the soldering pads. Use scissors for cutting.
15. Connect the tape sections using soldering. The wires are soldered to the designated contact pads marked “+ 12 V”, “-12V”. Soldering time should not exceed 5 seconds at a soldering iron tip temperature of no higher than 280″C.

In this article I answered the question How to connect an LED strip? There is also an analysis of the main difficulties of how to connect an LED strip when installing LED strips.

This is an artificial light source, which is a narrow flexible tape with conductors up to 5 m long, on which LEDs are installed equidistantly. The LEDs on the strip are divided into groups. Each group consists of several LEDs connected in series and is a complete circuit, which allows you to cut the tape crosswise into segments of any length that is a multiple of the length of one group.

LED strips

LED strips are produced monochrome, glowing in only one color (red, blue, green, yellow or white) and universal (R G B), the glow color of which can be changed independently using the remote control, including one of the primary colors or choosing any existing in nature .

It is also possible to turn on a mode in which the color of the LED strip will change smoothly over the entire range with a given rate of change over time.

R G B LED strips

Based on the organization of light emission, R G B LED strips come in three types.

The first type of strip uses LED-R-SMD3528 or LED-R-SMD5050 (red), LED-G-SMD3528 or LED-G-SMD5050 (green) and LED-B-SMD3528 or LED-B-SMD5050 (blue) , soldered in threes side by side in repeating triads along the entire length of the tape. Changing the glow color of the tape is achieved by group changing the glow intensity of the LEDs of each color. Such LED strips are well suited for interior lighting in cases where the LEDs are hidden from human eyes. If the LEDs are visible, the color change will be less effective.

R, G and B LEDs of the SMD3528 series have a size of 3.5 × 2.8 mm 2 and emit a luminous flux from 0.6 to 2.2 lumens, depending on the color of the glow. LEDs of the SMD5050 series are larger in size (their size is 5 × 5 mm 2) and accordingly they shine brighter, the luminous flux is from 2 to 8 lumens, depending on the color of the glow. Therefore, by the size of the LEDs soldered on the strip, even without knowing the technical characteristics, it is easy to determine which of them will shine brighter.

The second type of strip uses R G B LEDs of the LED-RGB-SMD3528 or LED-RGB-SMD5050 series. Distinctive feature These LEDs are that three LEDs are mounted in one housing - red, green and blue. Therefore, their luminous flux is much lower and is only 0.3-1.6 lumens for LED-RGB-SMD3528, and only 0.6-2.5 lumens for LED-RGB-SMD5050. But due to the fact that the color emitters are located practically at one point, high efficiency of color gradation is achieved.

More recently, a new type of LEDs WS2812B (has four pins) and WS2812S (has six pins) have appeared. According to geometric dimensions and appearance these LEDs are no different from LED-RGB-SMD5050. However, thanks to the installation of the WS2811 PWM controller in the WS2812 LED housing, it became possible to control each of the LEDs installed on the LED strip personally using just two wires.

Thus, designers have the opportunity to change the glow color of any section of the tape, regardless of its length, at their discretion. The widespread use of LED strips based on WS2812 LEDs is hampered by the high price and the need to use an expensive specialized controller. Without supplying a control signal from the controller to the WS2812 LED, it will not light.

LED strip marking

LED strips are marked by all manufacturers, usually in the same way international standard. The protection class in the marking is indicated in accordance with the requirements of the standard for the protection of electrical equipment from external factors IEC-952.

Let's consider, for example, how the LED strip LED-CW-SMD-5050/60 IP68 is labeled. LED - LED strip, CW - white light, SMD - made on the basis without output LEDs, 5050 - LED housing size 50x50 mm 2, 60 - 60 LEDs are installed on one meter of strip length, IP68 - in terms of protection level, the strip is designed for long-term operation depth (for example, to illuminate an aquarium or pool from the inside).

If the IP parameter is missing in the marking, then the LED strip does not have any degree of protection, that is, the degree of protection corresponds to IP00.

Resistance of LED strips to moisture

Based on the degree of protection from moisture, LED strips can be divided into three categories: moisture-proof, moisture-proof and moisture-resistant.

Moisture-proof ones can only be used in dry rooms where there is no high humidity. Waterproof ones are intended for use in rooms with high humidity (bathrooms, bathhouses, building facades, where direct contact of water with the tape is excluded).

Moisture-resistant tapes are designed to work directly in aquatic environment, for example in an aquarium, they can be placed for illumination at the bottom of the pool.

The photo shows an LED strip completely sealed with silicone, so the LEDs and resistors are reliably protected from water. Waterproof LED strips can be used without restrictions for outdoor advertising, lighting decoration of streets and buildings. When choosing a waterproof tape, it should be taken into account that part of the light flux is lost when passing through the silicone layer.

For outdoor decorative lighting, there are special LED strips called Duralight, which belong to the waterproof category.

Density of placement of LEDs on the strip

The brightness of the LED strip depends not only on the type of LEDs installed, but also on their number. The unit of measurement is considered to be the number of LEDs installed per meter of strip length. The more LEDs there are, the naturally greater the luminous flux will be. Typically, the number of LEDs per meter of strip length for 12 V LED strips ranges from 30 to 120 pieces. For LED strips designed for a supply voltage of 24 V, the number of LEDs can reach up to 240 per meter of length; in such strips the LEDs are placed parallel in two rows.

But we must take into account that the more LEDs per meter of LED strip length, the more powerful the power supply will be required and the more expensive the purchase will be. The choice of this parameter must be approached from the position of “necessary and sufficient”. For example, there are 30 LEDs per meter of tape, therefore, the distance between them is 3.3 cm, which is quite sufficient in the vast majority of cases.

Selecting an LED strip based on luminous output

The main lighting characteristic is the intensity of the luminous flux, which is expressed in lumens per meter (lm/m). The amount of luminous flux is determined by the type and number of LEDs installed on one meter of strip. Knowing the type of LEDs and their number, it is easy to independently determine the luminous flux.

For example, per meter of white light LED strip, 30 LEDs of the LED-CW-SMD3528 type (size 3.5 × 2.8 mm 2) are installed, each having a luminous flux of 5 lm. We multiply 5 lm by 30, we get 150 lm. This luminous flux is emitted by a 10-watt incandescent light bulb. If the strip is made on the basis of 30 LED-CW-SMD5050 LEDs (size 5 × 5 mm 2), already having a luminous flux of 12 lm, then 12 × 30 = 360 lm, which is equivalent to using a 24-watt incandescent light bulb. Everyone has experience in using incandescent lamps, therefore, using the above method, it is easy to determine the type of LEDs installed on the strip, their number and the length of the strip. And if the length of the tape has already been determined, then perform the reverse calculation.

Let's do the reverse calculation using a specific example. You need to make ceiling lighting in a room measuring 5 mx4 m. The perimeter of a room of this size will be 5+4+5+4=18 meters. You want to create soft and not very bright lighting. If you use incandescent lamps, their total power will have to be about 200 watts, the luminous flux from which will be 3000 lm (15 lm × 200). The length of the tape should be equal to the length of the perimeter of the room, that is, 18 meters. To determine the luminous flux that should be emitted by one meter of LED strip, you need to divide 3000 lm by 18 meters. This turns out to be 166 lm/m. For our case will suit strip with 30 LED-CW-SMD3528 LEDs per meter of length. The calculation was made without taking into account losses due to reflection from the ceiling, and they are at least 50%. Therefore, to guarantee room illumination, you need to choose a tape with twice the luminous flux. There are two options, either take a strip with 30 LEDs LED-CW-SMD5050, or LED-CW-SMD3528, but in the amount of 60 pcs. on the meter. The first option is preferable, as it will provide a guaranteed supply.

For R G B and monochrome LED strips, the calculation is performed in exactly the same way as for white strips.

LED strips are not always marked, which makes calculations difficult. But it’s very easy to find out the technical parameters of an LED strip if you use the data given in the reference table. Modern LED strips typically use three types of LEDs: SMD3014 (super-bright) 3.0 mm × 1.4 mm, SMD3528 2.8 mm × 3.5 mm and SMD5050 5.0 mm × 5.0 mm. Therefore, by the size of the LEDs, you can determine what type of LEDs are sealed on the strip. By counting the number of LEDs per meter of length, using the reference table below, you can obtain data on the technical characteristics of the LED strip.

Table of main characteristics of LED strips
for voltage 12 V

Using the table, it is easy to select the type and length of the LED strip - analogous to incandescent light bulbs. For example, to replace one 80 W incandescent light bulb with an LED strip, you need to take 8 meters of SMD3528 (30) or two meters of SMD3528 (120) or SMD5050 (60) LED strip.

How to connect an LED strip to the mains

Connecting the LED strip to the vehicle's on-board network

LED strips are ideal for direct connection to the vehicle's on-board network. The main thing is that the tape matches the supply voltage to the voltage of the vehicle's on-board network. For passenger cars, you need to choose a waterproof tape designed for a supply voltage of 12 V, for trucks - for 24 V.

What voltage is the battery installed in the car for, this is the voltage you need to take the tape for. When connecting the LED strip to the vehicle's on-board network, it is necessary to observe the polarity; the strip has the symbols “+” and “–”. If the polarity is reversed, then nothing bad will happen, the LEDs will just not light up.

Connecting the LED strip to a 220 V household power supply

Unlike electric lamps, LED strips cannot be connected directly to a 220 V household electrical network. They require a DC supply voltage of 12 V or 24 V. The supply voltage is indicated on the strip along its entire length. To obtain the required voltage, voltage converters are used.

While there is no established terminology, they are called differently: drivers, adapters, converters, power supplies, power supplies. All these words refer to one device that converts 220 V AC mains voltage into DC voltage of the required value, for tapes depending on the type, 12 V (often used) or 24 V (rarely used, usually in RGB tapes).

To select a power supply for an LED strip, it is important not only the value of the constant voltage at the output, but also the amount of current that it can supply to the load. To select the appropriate power supply for a particular case, you need to find out the total amount of current that all installed LED strips will consume.

An example of calculating a power supply for an LED strip

For example, let’s select a power supply unit (PSU) for the LED strip that we selected above for ceiling lighting. Typically, the current consumption of a tape meter is indicated in the accompanying documentation, but if there is none, then it is easy to perform the calculation yourself. It is enough to multiply the number of installed LEDs by the current consumption of each of them.

We chose an LED strip with installed LEDs of the LED-CW-SMD5050 type, the length of the strip is 18 meters, and there are 30 LEDs per meter of length. The total number of LEDs is 18×30=540 pcs. One LED-CW-SMD5050 LED (according to the reference table) consumes a current of 0.02 A, therefore the total current consumption of the entire backlight will be: 540 × 0.02 A = 10.8 A.

But we did not take into account that the LEDs with a strip supply voltage of 12 V are connected three in series through resistors, therefore the calculated current must be reduced three times: 10.8 A / 3 = 3.6 A. But in one LED-CW-LED housing SMD5050 contains three elementary LEDs, so the resulting current must be multiplied by 3. That is, the resulting current will be 10.8 A. As a result of the calculation, it was determined that a 12 V power supply with a permissible load current of up to 10.8 A is required.

To calculate the power of the required power supply, you need to multiply the voltage by the current: 12 V × 10.8 A = 130 W, it turns out that you need a power supply with a power of 130 W. For reliable operation of the power supply, a 20% power reserve is required. As a result, a 156 W power supply will be required. In practice, you can use any power supply that meets the necessary requirements.

Design and installation of LED strip

On a flexible plastic tape up to 5 m long there are thin copper conductive tracks of the required configuration. LEDs of the SMD3528 or SMD5050 type and current-limiting SMD resistors of the P1–12 type with a power of 0.125 W are soldered to the tracks. Please note that the designation of an LED is based on its size, for example SMD5050 has a size of 5.0 mm x 5.0 mm. With a supply voltage of 12 V, three LEDs connected in series and one or more current-limiting resistors are installed. The number of resistors is determined depending on the amount of power dissipated on them. The resistor can be installed anywhere in the circuit; in the diagram it is located on the positive side, you can also install it on the negative side or between any LEDs.

Electrical circuit and wiring diagram
LED strip segment

Resistor markings

The resistor is marked with the number 151. This means that the resistor value is 150 ohms. The markings are easy to decipher. It is indicated by a three-digit number. Last digit in the number says how many zeros should be added to the first two digits. For example, the resistor is marked 153, which means you need to add 3 zeros to 15, we get 15,000 Ohms.

For clarity, I have provided an eclectic wiring diagram below. A complete LED strip circuit consists of a large number of such circuits connected in parallel. With a supply voltage of 24 V, the number of LEDs connected in series in the circuit can reach up to 10 pieces. Pay attention to the markings of the LEDs, on the side connected to the cathode (minus), the corner of the LED body has a cut. Bottom right corner of the photo.

Connection and fastening of LED strips

The side of the strip opposite the LEDs has an adhesive layer protected with film. In order to secure the tape to the surface, it is enough to remove the protective film and apply the sticky side to the installation site. When organizing lighting using LED strips, often a length of 5 meters is excessive, so it is possible to cut the strip into pieces. The places where the tape can be cut are indicated by the image of conventional scissors and the cutting line. The step of cutting the LED strip into segments is determined by the number of LEDs connected in series. Near the cut line, there are contact pads on both sides that allow you to solder wires to them in case of splicing strip sections together. You need to solder very carefully with a low-power soldering iron.

Next to the contact pads there is a marking for the connection polarity and the supply voltage. There are special clips that allow you to connect LED strips together without soldering.

Conductors for connecting to the power supply are usually already soldered to one end of the LED strip. To connect monochrome tapes, two wires are required, for RGB tapes - four wires: black (the common one is connected to the positive terminal) and three color ones. The length of the wires is no more than half a meter, and if the power supply cannot be installed next to the LED strip, then the conductors will have to be increased to the required length.

LED strips are indispensable when you need to provide lighting or illumination over a long length. Only LED strips that are not protected from moisture can be cut into pieces, that is, only those that are intended for indoor use. It is unacceptable to cut waterproof and moisture-resistant LED strips without subsequent sealing.

To eliminate this drawback, LED modules have been created that allow interior lighting and illuminated advertising to be carried out easily, quickly and reliably. The scope of application of LED modules in practice is limited only by human imagination. Modules for lighting in a car are especially convenient. It is enough to connect it via a fuse to the on-board network and glue or secure the module with self-tapping screws inside the car interior or on the outside.

The design of LED modules consists of a shallow bed made of plastic or metal in which a PCB with LEDs. The top of the board is filled with transparent silicone. This ensures protection against moisture and splashing water. The LEDs are connected in the same way as in the LED strip above.

On the outside of the bottom of the crib there is a sticky layer, which can be opened by removing the protective film and the module can be fixed on any flat surface. It is possible to attach modules to the eyes using self-tapping screws. All lighting and electrical calculations given above on the page for LED strip are also valid for LED modules.

Rectangular LED modules are sold in the form of blocks; in the photo there is a block of 20 modules.

The modules can be easily separated from the block one by one or in groups. Electrically, all modules are already connected to each other. It is enough to supply power to any outermost one and the LEDs on all modules will light up. Blocks can be increased in any quantity by connecting them in parallel.

About choosing the wire cross-section for connecting LED strip

An LED strip consumes little power, and the current consumption for a strip length of one meter, even the brightest SMD5050 (60), is no more than 1.2 A. Therefore, you don’t have to think about the cross-section of the wire when connecting such a piece of strip; almost any available voltage will do. stranded wire by hand.

But when connecting an 18-meter long LED-CW-SMD5050(30) strip, which we selected to illuminate the ceiling of the room above, you should seriously think about how the total current consumption will be 10.8 A. Unfortunately, I didn’t find it anywhere, what current is allowed along the copper path of the tape itself. But, knowing the power consumption of one meter of LED strip and the supply voltage, I calculated the amount of current that LED strips of different lengths of popular types would consume, and summarized the results in a table.

Since LED strips are produced with a maximum length of up to 5 meters, the manufacturer must provide the required cross-section of the tracks that can withstand the current consumption of the LED strip, and you can take its value as the basis for developing a wiring diagram for connecting the LED strip to the power source.

Based on economic considerations, the load current margin of the tracks does not exceed 20%. Therefore, it is not permissible to connect all four of our strip sections in series, soldering the end of one section with jumpers to the beginning of the next LED strip, since a current three times higher than the permissible one will flow through the conductors of the strip connected directly to the power supply.

This will lead to overheating of the first tape, which can lead to its failure, and a weak glow of those switched on behind it. Therefore, it is necessary to connect each strip separately directly to the output of the power supply using a double wire with a core cross-section of at least 0.5 mm2. Below is a typical diagram for connecting LED strips to a power source when organizing room lighting by installing LED strips along the corners of the ceiling behind the eaves.

Since one power supply is designed for a current consumption of 6 A, we had to use two identical blocks, each powering half the length of the backlight. The switch connects both units simultaneously. If you use a double switch, you can turn on the tapes in sections. By connecting parallel sections of the tape to the power supply, you can turn them on individually or all at the same time, changing the lighting design. RGB strips are connected using exactly the same wiring diagram. Only instead of two wires, 4 are laid. One common and one for each color.

If one powerful power supply is installed at a considerable distance from the strips, then it is advisable to stretch a couple of thick wires from the power supply to the LED strips. You can select the required wire cross-section for a given current using the table. For example, for our case, with a current of 10.8 A, you will need a wire with a core diameter of 1.6 mm (cross section 2.0 mm 2). Place the distribution box and, using thin wires, connect the tapes through the terminal block or by soldering to the incoming wire from the power supply. In each specific case, an individual decision must be made based on the boundary conditions.

Powerful power supplies usually have large dimensions, and it is often more advisable to use several less powerful units, placing them in close proximity to the LED strips.

• Incorrect installation and connection with errors

Here are the main three rules and mistakes that you need to pay attention to first.

1 rule

The LED strip is connected in parallel, in sections of no more than 5 meters each.

It is even sold in reels of this meter. What if you need to connect 10 or 15m? It would seem that you connect the end of the first piece with the beginning of the second and you're done. However, such connection is prohibited. Why is this so accepted?

Because five meters is the estimated length that the current-carrying tracks of the tape can withstand. With a longer length, the load will exceed the permissible one and the tape will definitely fail. In addition, uneven glow will be observed. At the beginning of the strip, the LEDs will shine brightly, and at the end they will be much dimmer.

This is what a parallel connection diagram for LED strips with a length exceeding the permissible length will look like:

In this case, the tape can be connected both from two sides and from one. Connecting on both sides allows you to reduce the load on the current paths, and also helps to avoid uneven glow at the beginning and end of the tape.

This is especially important on a powerful tape - over 9.6 W/meter. This is exactly how professionals who have been installing LED products for many years advise connecting. The only big drawback is that you have to drag additional wires along the entire lighting.

Rule 2

The LED strip must be mounted on an aluminum profile, which acts as a heat sink.

During operation, the tape heats up, and this temperature negatively affects the LEDs themselves. They simply overheat and begin to lose brightness, gradually degrading and collapsing.

Thus, a tape that could easily work for 5-10 years without a profile will burn out in a year, and maybe even earlier. Therefore, the use of aluminum profiles in LED backlight Necessarily.

The only tape where you can do without it is SMD 3528. It is low-power, only 4.8 W per 1 m and is not so demanding on heat dissipation.

Tapes filled with silicone on top especially need heat removal. In them, heat transfer occurs only through the substrate, from below. And sometimes this is not enough. If you also stick it on some kind of plastic or wood, then there will be no cooling at all.

Rule 3

The correct choice of power supply is a guarantee of long-term and safe operation of the entire backlight.

The power supply must be 30% more powerful than the LED strip.

Only in this case will it work normally. If you select it closely, exactly according to the power of all LEDs, then the unit will constantly work at its limit. Naturally, such work will affect the duration of operation. So always give him some extra.

Connecting LED strip

To install lighting using LED strip you will need:

Installation of 220V power supply

If you have not completed electrical installation work, then you must first supply 220V voltage to the connection point of the tape. To do this, ditch the wall, or lay a cable channel and stretch a three-core cable VVGng-Ls 3*1.5 along it. Lead it directly to the distribution box where the power supply for the LED strip will be connected.

You can use the existing junction box where the main lighting is connected. The main thing is that the space allows you to freely connect additional wires and terminal blocks.

It is advisable to install the switch on the LED strip on the 220 Volt wires, and not in front of the strip on the outgoing 12-24V. In this case, the unit will not work continuously. Moreover, it is contraindicated for pulse units to operate without load. In addition, this will increase the level of security.

Pre-check and do not confuse phase, neutral and ground. Most often, zero happens blue, the grounding conductor is yellow-green, and the phase conductor is of any other colors.
But you can’t trust color coding alone! More details on how to distinguish zero and phase without errors can be found in the article “How to determine phase and zero in electrical wiring.”

Next, you need to lay a cable from this junction box in a groove, corrugated sleeve or in a cable channel to the future location of the power supply. To place it, install a convenient shelf. It can be made from pieces of plywood or drywall. Place a dimmer nearby.

Connecting the power supply

Having stretched the cable to the block, you can proceed directly to connecting the wires.

• connect the phase wire to connector L

• blue wire - zero, to terminal N

• yellow-green - to the terminal marked as Pe or with a ground symbol

Dimmer connection

Now you need to connect the dimmer. Here use flexible installation wire PuGV 1.5mm2 different colors. For example, black (for negative contacts) and red (for positive ones).

• measure and cut the required wire size

• clean the ends and crimp them with NShVI tips

First of all, connect the ends from the power supply side. Connect the negative wire (black) to the terminal marked –V. Positive wire (red) with terminal marked as +V.

Both wires must be connected to the dimmer side Power IN(input power). Connect the red wire on the dimmer to the positive terminal DC+, and the other wire to the minus terminal DC-

Next comes the installation work of laying the wire again. You stretch it in a corrugation from the dimmer to the point of connection to the LED strip. Use the same PuGV. If the total length of the LED strip and backlight exceeds 5 meters, the strips are connected in parallel. Moreover, each of them is supplied with separate power.

Proceed to connect the wires to the dimmer terminals. They usually have an inscription and are designated as Output Led. For reliable contact, it is better to crimp the stripped ends of the cores with tips.

Installation and soldering of wires on LED strip

You can proceed to installing the tape itself. To do this, you need to measure it and cut it into the required pieces. This can not be done in any place, but only where the dotted line is applied or scissors are drawn.

After cutting, the wires can be soldered to special contacts on the tape. For the same purposes, as well as for connecting individual pieces of tape to each other, connectors can be used.

Look for the negative terminal and connect black wires there. Accordingly, another wire goes to the plus contact - red. Do not heat the soldering iron to maximum, otherwise you will easily burn the substrate. Recommended soldering time is up to 10 seconds.

The opposite ends are also cleaned and NShVI tips are installed on them.

Remember once again that for better cooling, you only need to lay the LED strip on an aluminum profile. It is installed in advance.

After all this work, all wire strands are brought out to one place and connected to the corresponding supply wires, observing the phasing (positive and negative contacts).

The connection is best made using Wago terminals.