Basic knowledge and installation of LED light strips
LED light strip basics: Light strip is the abbreviation of LED light strip. Most people are not used to the long noun, so they omit the LED in front and just call it light strip. This name of light strip also includes many old-fashioned light strips such as large two-wire, large three-wire, round two-wire, etc., which directly connect LEDs with wires without FPC or PCB, and of course also include Flexible Light Strips and hard light strips.
The structure of Led Light Strips There are two types of LED light strip structures: one is the ordinary type, which is a series-parallel circuit structure; the other is a combination type, which is the structure used by the fantasy light strip, which contains an integrated circuit and a timing control circuit.
The following will use commonly used LED light strips to explain the relevant issues about LED light strips:
1. What materials does the LED light strip consist of?
LED light strips are composed of FPC, LED, chip resistors, waterproof silicone (there is an article introducing the waterproof treatment method of LED light strips, which you can refer to), connecting terminals and other materials.
2. What is the circuit structure of LED light strips?
The circuit structure of conventional LED light strips is a series-parallel circuit. Most of the LED light strips wholesaled to us are 12V powered LED light strips, which use three LEDs and a chip resistor in series to form a group circuit; and each LED light strip is composed of 10 groups of circuits connected in parallel. The advantages of this circuit structure design are:
A. Using resistor voltage divider can effectively ensure that the LED works under the specified rated voltage, so as not to shorten the service life of the LED due to the input voltage exceeding the rated voltage of the LED.
B. Parallel shunt can effectively reduce the impact of input rated current on each group of LEDs through parallel circuits, allowing the LEDs to stabilize within a current range, thereby greatly improving the service life of the LEDs.
C. Parallel constant voltage, because each group of LEDs is in parallel structure, therefore, cutting off one group will not affect the normal use of other groups, which can effectively save installation costs and avoid waste.
3. What is the physical structure of LED light strips?
LED light strips are divided into 4 types according to width: 6mm/8mm/10mm/12mm, and 6 types according to LED size: 0603, 0805, 1206, 1210, 5050, 5060. So what is the physical structure of each LED light strip? Let's take the conventional LED light strips (led5050 220v soft light strips) we provide as an example to explain their physical structure.
Since the LED light strip needs to be divided into spacings according to the specific length of the light strip, the number of LEDs and the cutting position, no matter what kind of LED light strip it is, the arrangement of its physical structure is calculated according to the following formula:
(LED light strip length - cutting position width x number of cuts) / number of LEDs = LED spacing.
Number of LEDs/3 = Number of SMD resistors
Features of LED light strips: 1. Soft and can be curled at will.
2. Can be cut and extended.
3. The light bulb and the passage are completely wrapped in flexible plastic, with good insulation and waterproof performance, and safe to use.
4. Strong weather resistance.
5. Not easy to break and long service life.
6. It is easy to create graphics, text and other shapes; it has been widely used to decorate and illuminate buildings, bridges, roads, gardens, courtyards, strata, ceilings, furniture, buses, lakes, underwater, posters, signs, and so on.
The working principle of LED light strip is that each section is a unit, each unit has a fixed number of light-emitting diodes and distributed current-limiting resistors. When cutting, it must be cut according to the unit, otherwise this section will not light up. Each unit is connected in parallel and withstands the power supply voltage, which is DC 200V, 24V, 12V, 5V, etc. There are positive and negative poles in the connection between the power supply and the light strip. Reverse connection will light up.
How to install LED light strips
1. Indoor installation: When LED light strips are used for interior decoration, they are very easy to install because they do not have to withstand wind and rain. Take the LED light strips produced by Guanghong Electronics as an example. Each LED light strip has a self-adhesive 3M double-sided tape on the back. When installing, you can directly tear off the sticker on the surface of the 3M double-sided tape, and then fix the light strip where it needs to be installed, and press it flat with your hands. What if some places need to be turned or are too long? It's very simple. The LED light strip is a circuit structure composed of 3 LEDs in series and parallel. Every 3 LEDs can be cut and used separately.
2. Outdoor installation: Outdoor installation will be exposed to wind and rain. If 3M glue is used for fixing, the adhesiveness of 3M glue will decrease over time, causing the LED light strip to fall off. Therefore, the card slot is often used for outdoor installation. The method for cutting and connecting is the same as that for indoor installation, except that waterproof glue is required to strengthen the waterproof effect of the connection point.
3. Power connection method: The general voltage of LED light strips is DC 12V, so a switching power supply is required. The size of the power supply is determined by the power and connection length of the LED light strip. If you do not want to use a power supply to control each LED light strip, you can buy a relatively high-power switching power supply as the main power supply, and then connect all the input power supplies of the LED light strips in parallel (if the wire size is not enough, you can extend it separately), and the main switching power supply is used for power supply. The advantage of this is that centralized control can be achieved, but the inconvenience is that the lighting effect and switch control of a single LED light strip cannot be achieved. You can decide which method to use.
4. Controller connection method: LED marquee light strips and RGB full-color light strips require a controller to achieve the changing effect, and the control distance of each controller is different. Generally speaking, the control distance of a simple controller is 10 to 15 meters, and the control distance of a remote controller is 15 to 20 meters, and the longest control distance can be 30 meters. If the connection distance of the LED light strip is long, and the controller cannot control such a long light strip, then a power amplifier is needed for tapping.
5. Pay attention to the connection distance of the LED light strip: Generally speaking, the maximum connection distance of the 3528 series LED light strip is 20 meters, and the maximum connection distance of the 5050 series LED light strip is 15 meters. If the connection distance is exceeded, the LED light strip will easily heat up, which will affect the service life of the LED light strip during use. Therefore, when installing, you must install it according to the manufacturer's requirements and avoid overloading the LED light strip.
