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skeeler Newbie
Joined: 11 Aug 2005 Posts: 23 City: Omaha
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Posted: Aug 17, 2005 8:34 am Post subject: LED Help.....Is this correct??? |
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Hello all!! Thought I would run this past all you tech junkies out there. I just wanted to make sure I had the wiring correct before I go to the install phase. I am adding some LEDs to the interior of my boat. All the LEDs are 2.1volt, add the current provided will be 12volt, also the LEDs are rated to 30ma. Is the wiring digram I made below correct? |
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Jensen Wakeboarder.com Freak
Joined: 06 Jul 2004 Posts: 3108 City: Chico
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Posted: Aug 17, 2005 2:42 pm Post subject: |
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ya, that looks right. but i would personally use 100 ohm resistors, since the min forward voltage is 2.1, and the max is 2.5, i would pick somewhere in between, so if you use 100 ohm resistors, the leds will be powered at 2.3v so you'll get a bit more kick out of them.
your soldering these together right? |
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AndyDeeJay Outlaw
Joined: 20 Jul 2004 Posts: 239 City: Belfast
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Posted: Aug 18, 2005 9:15 am Post subject: |
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If the alternator is kicking out 14.5V max and you take the forward volt drop across the series load to be 10V then you will need to drop 4.5V in the resistor. The curent is 0.030A. R=V/I. R=4.5/0.03, R=150ohms
If you go down to 120 or 100 you might cook those LEDS. Put is 150Ohm to be safe.
P=VI= 4.5x0.03 = 0.135watts. Use 1/4watt resistors. _________________ Wakeboarding is so Kool in Ireland! |
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