Q:How much is the voltage across the 20 LED lamps in series?

Don't know what kind of LED, if it is ordinary bright LED words, according to different colors, the rated voltage between 3.6-3.8V (current allowable level <20mA), you can be calculated according to the amount of estimates, as long as the control current should not exceed 20MA no problem

Q:The number of lights in the LED string

In general, 1210 specifications of the band is 60 LED per meter, 5050 specifications of the band is 30 LED per meter, the special has 60 LED per meter.

Q:Section LED lantern, no controller, can shine principleTwo now reduced brightness string string

Led 2 polar tube inside chip oscillator circuit, and the general appearance led 2 polar tube without distinction, only connected to the power supply of two kinds of color turns light, 1 seconds, I bought the 5MM red, blue autoflash. From the appearance of the series, but not necessarily in series

Q:Rated voltage of LED lamp string

When normal luminescence, each LED voltage drop is more than 2 volts, the current is about 15mA, to use 220V direct current should be connected in series with nearly one hundred led, or in the LED circuit series resistance, so that the series circuit current is about 15ma.

Q:220vled water lamp string how to connect, that is, 220 of the electricity

The time of the water lamp is controlled by adjusting the capacity value of the capacitor.

Q:I want to do a string of LED lights that can use batteries. About 55 or so. The lights are 5MM blue. How can I work? Urgent urgent!!

55, it is blue, blue and white as the power is too large, large power consumption, even in parallel connection, the voltage of 3V certainly do not move with the battery, just to be able to provide 4.5V voltage, and three batteries of 5 words for a while no electricity, regulated power supply with advice, use parallel to, from the 3V voltage can be gradually increased, the brightness is just perfect, too high voltage lamp

Q:How does the LED light string flash?

Because of the special volt ampere characteristics, LED can not use constant voltage driving mode, but is driven by cross flow. The direct drawback of cross flow drive, however, is heat. So people invented the drive mode of pulse drive. For example, 0.5 seconds per second, so that the amount of heat in the LED is reduced by half. Then turn the frequency up to 100 times per second, lighting for 0.005 seconds each time. At this point, the power of the LED is not the same, and people do not feel blinking. What's more, in this driving mode, an approximate cross flow drive (that is, the current is not necessarily precise) can be simplified, which simplifies the drive circuit (the precise cross flow source is very complex)

Q:What are the power connections for the LED light string?

This advantage can be centralized control, inconvenience is unable to achieve a single LED light string lighting effect and switch control, which specific way can be measured by their own. I use the LED lamp string is Zhongshan Greenman with total power and parallel connected to

Q:Why are there three lines for the controller of the LED light string? What are they?

Common positive (red line +) is the positive pole for each street lampThree road cycling (blue line) this four lines are respectively connected with the four colors of LED tube anode side run. When the positive pole is connected to the common cathode, remember that the resistor must be connected first to connect to the positive electrode of the LED tube. The bright output (white) is the word to make it bright

Q:Example: if I want to do a 40 head low voltage lamp string, do 10 lights, 1 loop, transformer is 150MA, then how can I calculate the resistance? The grid is 60 Hz of China's power grid! Give a formula, and then count the examples. What is it?! Thank you

In general, LED lamps need constant current to drive, and the voltage may be adjusted according to the aging degree of the LED lamp.