help for controlling power leds (10*1 w) brightness with pwm and UNO

abrisham:
Thanks leo for your help...

1).If i split that string in to 2*5 led the current will drop to 500mA and voltage to 4.8 v for each led is it correct?

2).If yes what happens to led with that extra current (200mA) and voltage about 1.5 v??

3). if one of 2 fails suddenly the other ones could be damage by heavy amp and volt... is there any way for protection?

  1. No. 24volt supply, two strings of five, two 300mA constant current boards, two Arduino PWM pins.
    Those LEDs have a Vf (working voltage) of about 3.3volt each.

  2. 300-350mA is all a 1watt LED can take.

  3. No. If one fails open circuit, the whole string will be off. If one is shorted, the constant current board will still send 300mA through the string.
    Leo..