I want to buy 5050 strip led 10m long. In the spec they always write the current consumption is 1.2A/meter (which is 0.24w per led), so for 5m I have 6A. But, all LED dimmers and controllers they sell in Ebay fit to 4A per channel (for example), where channel is R, G or B, so I'm confused. Is the 6A current consumption is for 1 color only? so for RGB it's 18Amps? Do these strips has actually 3 leds for each color so it is 0.24w per color per led? Thank you!
While it might vary based on the specific strip you buy, taking the average case: 12v, 3 RGB leds per segment, and no controller IC. Each segment will have a current limiting resister for each color, nominally set for 20ma at 12v. Remember, current stays the same throughout the circuit, so the three blue leds will all share a single 20ma of current, same for the red and green ones. That's 20 x 3, 60mA per segment.
A 30 led per meter strip will contain 10 segments per meter. 60 mA x 10 = 0.6A per meter. A 60 led per meter strip has 20 segments per meter. 60 mA x 20 = 1.2A. 0.4A per color.
A 5 meter Roll of 60 leds per meter will take 6A, for all three colors, on at the same time.
Of course, your milage may vary based on your specific led strip.