The LED driver is used to convert the city power supply (in China as an example, the AC power with a power frequency of 50 Hz and a voltage of 220V) into the voltage and current range required for the stable operation of the LED light source.
So, how to choose the driver, the key lies in what your LED light source is. When the LED is working, the current needs to be stable. Because according to the diode volt-ampere characteristics of the LED, you will find that when the forward voltage is added above the turn-on voltage, a slight voltage fluctuation will cause an exponential fluctuation in the current flow through the light-emitting diode LED. Therefore, it is necessary to pay attention to the fluctuation of the voltage and current of the LED during normal operation.
II. What are the classifications of drives/power supplies?
This is related to the classification of off-the-shelf drives, which are:
● Constant voltage driver
● Constant current driver
● Constant current and constant voltage driver
We will not discuss the RC buck solution with poor quality and stability here.
Regarding the driver, there are many technical parameters, such as: input voltage, input current, output voltage, output current, power factor, conversion efficiency, harmonics, ripple, stroboscopic, ambient temperature, protection level, and so on. Faced with these professional terms, we don't need to panic. Generally, we only need to pay attention to: input voltage, input current, output voltage, and output current, and then we can match the driver and light source.
Regarding the input, we only need to look at the input voltage. China has AC 220V input, in addition, Japan, the United States AC110V, and some countries, such as Malaysia, will be AC240V. Most countries in Europe, that is, AC220V voltage.
Regarding the output, it is necessary to figure out the output voltage and the output circuit before it can be properly matched.
● Constant voltage driver
A constant voltage driver is a driver whose output is a constant voltage, usually outputting 5V, 12V, 24V, 48V, etc. Generally, it is DC direct current; suitable LED light sources are generally low-voltage light strips. There are also some light sources, such as outdoor pool lights, etc., which also require low-voltage 12V input. Mainly to avoid electric leakage to hurt people.
If the voltage is constant, how is the current determined?
The current is determined by how long the light strips are. Almost all light strips have chip resistors on them. The function of the resistor is to limit the current to ensure that the current flowing through each lamp bead is relatively stable.
Because the principle of the light strip is that 3 or 6 lamp beads are connected in series first, and then in parallel. Therefore, the current will be the sum of the currents of all strings. The output current of the drive will be adaptively adjusted according to the length of the light strip.
Steps to match LED strips light
Step 1: Determine the voltage of the low-voltage light strip
Low-voltage light strips are very easy to judge, generally on the flexible version of the light strip, with a clear indication of DC12V or DC24V.
Therefore, you just need to find the right output voltage, and you're sure to be right, but it's just the first step. The second step will be to choose how much power is appropriate.
Step 2: Power selection
It mainly depends on your light source load.
For example: your light strip is 12VDC, one meter is 12 watts, there are a total of 4 meters of light strips, then the total wattage of the light strip is 12x4=48W. Then you need to choose a constant voltage driver above 48W. There are conventional wattages on the market, such as: 45W, 50W, 60W, 75W, 100W, 150W, 200W, 350W and so on. Then, there is no problem in choosing one larger than 60W.
Why can't I choose 50W? Mainly because we need some margin for the constant voltage driver. Although the constant voltage driver of the big brand can output at full load, it is better to leave some margin than nothing. Not to mention those who falsely mark the maximum power. How much is generally reserved? The industry generally believes that about 20% is sufficient. Therefore, 20% more than 48W is about 58W, and there is no problem in choosing 60W.
So, can I choose a bigger one? For example, there is a 150W 12VDC output constant voltage driver on hand, can it be used? Of course, no problem. A car can carry 5 people, and now it only takes two people, for the same reason. If it is a new purchase, then it is enough, and you don't need to spend unnecessary money.
● Aluminum slot
The light trough is equivalent to the shell of the light strip, similar to the mobile phone case of the mobile phone. The light strip and the light trough are a perfect straight line. If the light strip is used with the light trough, it can only be installed straight. Generally, when the light strip is used with the light trough, stick the light strip in the light trough, and then fix the light trough to the position with the clips and screws.
When choosing a straight light strip, you need to pay attention to the material of the light trough. The life of the light strip is long, and the light trough can naturally not fall behind. Aluminum profile + PCD, not easy to oxidize, high light transmittance, temperature and cold resistance. The material design of the light trough will also determine the light emitting method and anti-glare dimension. The light trough has its own frosted feeling, and the light is even and soft without anti-glare.
The difference of the lamp trough will affect the light output of the lamp strip. Here are two common lamp troughs, 45° lamp trough and flat lamp trough.
In the ambient light around the bedroom bed, the height of the light strip installation and the plane will also lead to different choices of light troughs.
As shown in the figure below,
● If the height is greater than 20cm, it is recommended to use a flat-angle light trough.
● It is recommended to use a 45° light trough with a height of less than 20cm.
Flat light troughs are more convenient and friendly to cabinets within a right angle range, illuminating small dark corners.
The 45° light trough emits light farther and more evenly, and the tail light forms a halo, which provides a large area of ambient light and is suitable for ceilings and curtain boxes.
The above two installation methods are very convenient to disassemble, just stick and install and tear off, and the snap installation only needs to unscrew the screws and fill the wall.
The common features of the above two installation methods are convenient installation and easy disassembly. More importantly, after the decoration is completed, the need for ambient lighting is required. Even if the installation of the light strip is not considered before the decoration, you can still choose the light strip installed by sticking or snapping to supplement the ambient lighting of the decorative lighting of the home.
As long as you want! the cloakroom! Mirror edge! Under the bed! Under the cabinet! You can wear it anytime!
The light strip should be taken into consideration before the decoration, then embedded installation can be adopted, because the embedded installation of the light strip should use the embedded parts. After opening the wall, insert the embedded parts and lock them with screws into the embedded card slot, and then connect to the power supply. However, the light-emitting effect of the embedded-installed light strip is also different — the light strip is integrated with the wall, and there will be an illusion that the wall is glowing.
There are three types of embedded parts, internal angle, external angle and flat angle.
●Inside corners, it is recommended to install in concave corner areas.
●For external corners, it is recommended to install in the convex corner area.
●Flat angle, it is recommended to install it in flat areas such as ceilings and walls.
The embedded parts will have a matching PC lampshade, which will not directly expose the LED chips of the lamp strip. The lampshade can play an anti-glare effect, and the lamp strip will not be dazzling when viewed directly.