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:What's the average luminous current of an ordinary LED lamp string?

General LED patch to 0.2W, 0.5W, 0.2W lamp current is 60mA, 0.5W beads 150mA,

Q:LED lights string broken, how to repair?

Connect the electricity. Can be shorted one by one. It's shining. This is just short of bad beads.

Q:The number of lights in the LED string

Different LED number of LED light band price is different, and this is also to distinguish LED lamp belt price is an important factor.

Q:The top LED lights always burn the bulb in series

Do not know what kind of drive you are, try to reduce the current of LED, do not exceed the rated operating current of LED on the line. The method of reducing current is related to drive circuit, and the current limiting method is different for different circuits.

Q:Hanging on the tree string lights, each one is 10 meters long, with a controller, I asked the factory with the AB protection, but the manufacturers say that only do the general anti rain, no water, even the rain stop, I want to use plastic wrap, don't know? Which expert can give advice and advice? emergency

You can use the plastic wrap, mouth down, so even if again under the rain is not bad. Or glue the entire controller to the point where the water is likely to enter the water.

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!!

If it is a general common blue LED working current is 20 mA, voltage of about 2.5V can be lit, the battery power can be used in parallel, the benefits of this connection is one of the damage does not influence the normal operation of other LED. And each LED string to a current limiting resistor, LED protection lamp, prolong life, calculation formula of the resistance for V / 0.02A=: voltage current resistance: 3V, battery powered =3 / 0.02=150. You want to supply 55 LED batteries to work together, the total current is up to 0.02x55=1.1A, i.e. 1AH (ah) capacity of the battery can work 1 hours or so.

Q:The color temperature of LED light string

Refers to a standard blackbody heating, the temperature rises to a certain degree when starting from the color red - Orange - red - white - blue, gradually changed, a light source and the blackbody with the same color, we will at the time of the absolute temperature blackbody called the color temperature of the light source.

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