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| Thread ID: 47832 | 2004-08-07 00:02:00 | LED Help | hsv-b0y (5210) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 259011 | 2004-08-07 00:02:00 | Hey guys, I'm a little bored today so I've decided I want to hook some LED's up so the side of my case. The LEDs I want you you are out of a car spoiler, for the brake light. These LEDs are set up in series, so i would like to no where would be the best place to wire them too? 12v power supply, or a 3v power supply. Thanks, Luke |
hsv-b0y (5210) | ||
| 259012 | 2004-08-07 00:18:00 | Depends on the forward voltage rating of the LED's First thing to realise, is that LEDs are not like bulbs . As long as the forward voltage needs are satisfied, they must have their current controlled by a suitable resistor . Normal current for LED's is around 20 mA . If you ever run LEDs without a series resistor, then they are either dead, or very soon will be . Some esoteric models of LED will have a resistor built in, but very few . Forward voltage ranges are wide, but typically 2 - 6 volts for high brightness LEDs . If it (one LED) had a FV of 3 volts, and you were to run it from 12 v, then you need to limit the current to the above 20 mA with a resistor calculated as follows: 12v - 3v = 9v . Resistor = voltage divided by current, = 9 divided by . 02 Amps (20 mA) = 450 ohms . Nearest value is 470 ohms . Wattage rating of the resistor needed is current squared times resistance, = ( . 02 x . 02) x 470 = 0 . 188, so a standard 0 . 25 watt 470 ohm resistor in series with each LED would suffice (assuming VF=3v) If the module is presently designed for automotive use though, and you intend to leave them in series "as is" then it should already be optimised with series resistance for 12v . Cars are 12v . |
godfather (25) | ||
| 259013 | 2004-08-07 00:19:00 | if they are out of a car then it will be 12v (assuming you didn't modify the way the lights where setup). they won't draw much so connecting it to a molex should be ok. | tweak'e (174) | ||
| 259014 | 2004-08-07 00:22:00 | Thanks for that godfather, so my best bet we be to wire it from something thats 12v in there and easy to access....ie speaker? or fan powersupply? Sorry, im not very good with electrical setups as im not taking electronics at school :( i should have picked it! Thanks, Luke |
hsv-b0y (5210) | ||
| 259015 | 2004-08-07 00:53:00 | Connect to a spare molex for a disk drive would be better. Black = - 12 v Yellow = + 12 v NOT the "speaker", and avoid fans as some may be controilled by the motherboard. Pinout is here: www.computerhope.com |
godfather (25) | ||
| 259016 | 2004-08-07 01:03:00 | Thanks again GF, your a legend :) Now that I know where to plug it in, I'll have a go at wiring it up later. Thanks, Luke |
hsv-b0y (5210) | ||
| 259017 | 2004-08-07 15:03:00 | Hey all, thanks for the help! i got it successfully working, so i took some photos for you! Picture 1 (hsv-b0y.digibase.ca) Picture 2 (hsv-b0y.digibase.ca) Picture 3 (hsv-b0y.digibase.ca) Once again.... Thanks heaps! |
hsv-b0y (5210) | ||
| 259018 | 2004-08-07 15:10:00 | I'm not sure if that looks cool, or maybe it looks hot? But, are stop-lights the ideal thing for a 'puter's innards ?:| (Don't want to give it the wrong idea.) R2 |
R2x1 (4628) | ||
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