LED strips - Modern lighting devices, which are firmly entrenched in our lives. With their help, it is possible to perform not only lighting for decorative purposes, but also the device of full lighting in the premises of apartments and houses, industrial facilities and in transport. They have low power consumption, lighting quality that is not inferior to standard lamps, and can be easily mounted on any surface. This article will help to understand all the variety of LED strips, their principle of operation, application and will orient how to choose the right strip for any purpose.
Content
Principle of operation and design of LED strip
LED strip - A light source, which is a board with LEDs spaced equidistant from each other. The tape base is made of dielectric material with a thickness of 0.2 to 0.5 mm, it has conducting tracks and pads. LEDs and resistors for current limitation are installed on these mounting pads on the strip. The main element that performs the useful work of emitting light is the LED. Its principle of operation is based on an electron-hole transition when an electric current passes through the LED in the forward direction.
To work, the strip is connected to a special transformer that lowers the voltage from 220V to 12-36V. It can be made in a waterproof version or without, and may have a special self-adhesive layer for quick installation.
Types of LED strips
Manufacturers of LED strips produce a large number of such devices, which vary in size, number of LEDs per meter and other technical characteristics. Also, tapes can be made in different colors, degrees of tightness and have different options for glow.
One-color tapes
Monochrome or SMD (surface mounted device) ribbons are also known as one-color ribbons. surface mounted device - surface mounted device). Such a tape can shine only one color, depending on what color LEDs are installed on it. The most common and commonly used color is white. It is denoted by the English letter W and costs less than all other color options. Also popular LED tapes with red crystals (RR), blue (B) and green (G) colors-as these are the primary colors.
There are SMD tapes of intermediate colors, which are obtained by using a special composition on the LED crystal. Usually all intermediate colors shine less brightly than the main colors.
Ribbons of different colors are often used for decorative lighting in the interior of rooms or street décor. White tape is used as additional lighting for workplaces and is also successfully used for interior design.
White strips have different glow temperatures, by analogy with energy-saving lamps, they can have cold or warm light.
Multicolor RGB strips
Multicolor ribbons allow you to change the color of the glow with different controls. This effect is possible because of the multicolor LEDs mounted on the LED strip. The optical displacement of red, green and blue gives a variety of shades of illumination.
The color of the ribbon is controlled by special controllers that can transmit from 3 to 16 million shades. In addition, the advanced models adjust the automatic color change depending on user preference or preset algorithms.
RGB tape can not produce pure white color, so it is not used for additional or primary lighting. But there is a variety of ribbon, which in addition to different combinations of the three primary colors (red, green and blue) can separately shine in white. These tapes have the abbreviation RGBW (multicolor + cool white) or RGBWW (multicolor + cool white).
It is worth noting that multicolor tapes are much more expensive than single-color tapes, but their scope is limited only by a person's imagination.
Open and sealed
LED strips can be produced both in moisture- and dust-proof sealed version and in open type.
Open type LED strip components are not protected from moisture and mechanical influences. Such a strip is used only in dry rooms as a decorative illumination, hidden in furniture or room constructions. It is also used in a set with special protective housings for LED strips, which serve as external protection.
Sealed devices are protected from external influences with a special layer of silicone or other light-permeable material that does not conduct electricity. Protection class complies with IEC 60529 and is assigned according to the quality of the protection against penetration of objects and moisture.
Sealed LED strips are used in rooms with high humidity, as well as in the arrangement of street lighting of buildings and structures. Due to their protection against damage, they can be installed on stairs and other structures where mechanical impact on the tape is possible.
Running Fire Ribbons
Tape "Running Fire" - A special type of LED strip, which can change the color and brightness of each LED, regardless of the others. This is possible due to the special design of the board, which has addressable microcircuits to control lighting scenarios.
With this tape create special lighting effects that can not be performed with conventional RGB-tape. They are used for the decoration of entertainment facilities and the organization of lighting at various festivals and events.
Side glow tapes
LED strip, which has a side glow looks like a standard strip, except that the LEDs are located on the end part. LEDs of cylindrical type are mounted on the ends of such tape, which creates the effect of lateral light incidence with an angle of 120 degrees.
Such strips are used for decorative lighting, backlighting of TVs and various screens. Very often used by garage masters in creating backlighting in cars.
The main technical characteristics of LED strips
The distinction of LED strips is expressed not only in their tightness and color of LEDs, but also depending on other technical parameters. To choose a tape that will best fit the assigned tasks, it is important to know what characteristics you should pay attention to. The parameters include the supply voltage, type and size of LEDs used, the density of LEDs on the strip, length, leakage class and other properties. Let's take a closer look at each of them.
Supply voltage
LED strips most often have a voltage of 12, 24 or 36 volts. 12 volts are used standard tapes, which do not have high power and density of LEDs. More powerful devices work with a voltage of 24 V, rarely 36 V.
Regardless of which voltage (12 - 36 В) uses a device to work in standard 220 V electrical networks, they are equipped with special step-down transformers. If you give the LED strip directly to the voltage of the network, such a strip, of course, will burn out. Therefore, when connecting LED devices, it is important to understand the voltage at which the strip is connected.
Type and size of LEDs used
Type and size of LEDs, which are installed on tapes, are denoted by four digits. The first two digits indicate the length of the LED in millimeters, and the second - its width. By species, LEDs come in:
• 3528 - have a small luminous flux (about 5 lm per LED) and are used for decorative purposes, as they do not shine brightly enough.
• 5050 (5060) - A common type of LED strip, which is characterized by the large size of the LEDs and produces a glow of 12-14 lm per LED.
• 2835 - Strip with these diodes are used to organize the main lighting, because they have a high brightness (about 25 lm), but in the decor of such options are practically not used.
• 5630 - The brightest LEDs, which are used to illuminate all types of rooms. Diodes can produce up to 75 lumens, and when it heats up a lot. To protect against overheating they are mounted on special heat dissipating plates of aluminum or other thermally conductive material.
The density of the LEDs on the strip
The quality and brightness of lighting when using LED tapes associated with the density of LEDs. In other words, when buying LED strip, you need to pay attention to the number of LEDs in a meter strip. Standard products have a density of 30, 60, 90, 120 or 240 LEDs per meter length.
Some manufacturers produce versions of tapes with LEDs in several rows. This is typical for LED tapes such as "running lights" and other multi-colored tapes.
The main rule is obvious: the greater the density of LEDs on the strip, the higher the brightness of the tape and more opportunities to control color.
Protection level
Waterproof LED strip - an important condition for installation in rooms with high humidity, swimming pools, as well as on the street. There is an indicator that indicates the degree of protection against moisture or dust penetration into the body of the device or a direct impact on electronic components. In the labeling of the LED strip it is specified in English letters "IP" and two numbers.
The first number indicates the degree of protection against dust and other particles, the second about protection against water. The greater each figure - the more substantial protection for the LED strip. The maximum protection against dust and moisture is indicated by the label IP68.
Based on the conditions of use of the tape choose its degree of protection. For example, in living quarters with normal humidity tapes IP20 are used (that is, without protection), for the street suitable class IP55, but in swimming pools use IP67 or IP68.
Length
As standard, LED tapes are available in lengths of 5 or 10 meters. But, of course, there are tapes and other sizes. The main rule: try to minimize the number of connections. For example, if you want to buy 4 meters of tape, it is better to buy 5 meters and cut one meter from it than to buy two 2-meter tapes and then solder them to each other. The price is the same, but it simplifies installation. You can cut the tape along special cutting lines so that the performance of the product is not affected.
Deciphering the marking
The LED strip marking hides all the necessary information about its technical characteristics. For example, LED-RGB-SMD5050/60 - IP67 would mean the following:
- LED - the source of light is a LED;
- RGB stands for color. It can be R - red, G - green, B - blue, RGB - color and W - white;
- SMD5050 - type and size of LED;
- 60 - density of LEDs per meter;
- IP67 - degree of protection against dust and moisture.
Additionally the marking may indicate the length of the tape, the temperature of the luminescence of white tape and supply voltage.
How to assess the quality of the LED strip assembly
When you buy LED strip in the store, you need to visually assess the quality of its manufacture. It should not have a broken protective layer, consist of several tapes soldered together, look sloppy, and the LEDs should be distributed evenly throughout the tape.
If it is possible to connect the tape to the power supply and check the quality of lighting, it is worth to evaluate the uniformity of luminescence and brightness of the tape. The color should correspond to that specified in the technical specifications. The power supply must have more power than the tape with a reserve, to avoid overheating and failure.
