Why every LED module has a resistor?

Why every Channel letter LED modules has a resistor? The simple answer: to limit the current  in the LED to a safe value.

The detail factor as followed: LEDs are semiconductors, diodes in particular. The current flowing in an LED is an exponential function of voltage across the LED. The important part about that for you is that LED forward current is not linearly related with forward voltage. That is the most important concept of LEDs. Resistors aren抰 like that. The current and voltage in a resistor are linearly related.
Flexible LED Strips    www.bgocled.com

White windmill move follow the wind during the day is a beautiful landscape

 in the evening it turn into a bright light-emitting sculpture which can also be a beautiful night.

Unique LED light windmill located in the northern German city of Hanover, designed by the French artist Patrick Renault, he added decorative lights in large wind turbine blades and tower, make LED light bulbs shine colorful light with the the fan rotation produced fantastic results, LED power supply is also provided by the wind turbine, when the wind up, LED lights will be more bright, beautiful and shining in the night sky.
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