LED's In cup holders
I need TP for my bunghole
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From: OXNARD, CA. SoCal. "805", North of L.A.
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I have led questions
what is a good size? 5mm 10 mm
Also what is a good light itesity level? 5,000 mcd, 10,000 mcd, 20,000 mcd
you can get anyware from 10 to 1000 or more leds on ebay for cheap
but I don't know what to get
http://search.ebay.com/led-5mm_W0QQs...trypageZsearch
what is a good size? 5mm 10 mm
Also what is a good light itesity level? 5,000 mcd, 10,000 mcd, 20,000 mcd
you can get anyware from 10 to 1000 or more leds on ebay for cheap
but I don't know what to get
http://search.ebay.com/led-5mm_W0QQs...trypageZsearch
I need TP for my bunghole
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From: OXNARD, CA. SoCal. "805", North of L.A.
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Originally Posted by Mystic3030
THose are wayyyy too bright...prepare to get pulled over!
what is a good size?
what is a good light level?
Yup, i'm an A$$hole.
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From: Florida
Rep Power: 328 THe size doesnt matter, it just depends on how large of an LED you want in there. MCD is the brightness rating. I'm not sure how to compare them, as I havent worked with LEDs really. I would find out from Marcus how many MCDs the LEDs he used are rated at, and get half of his rating as the eye can usually only distinguish between rate doubling or halfing. (ie: he used 10,000, so you get 5,000) Also make sure you get the proper resistors so that you dont blow your LEDs in a day. Also, your life will be easier if you get 12v LED's instead of 3.6-4.
I need TP for my bunghole
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Originally Posted by Mystic3030
THe size doesnt matter, it just depends on how large of an LED you want in there. MCD is the brightness rating. I'm not sure how to compare them, as I havent worked with LEDs really. I would find out from Marcus how many MCDs the LEDs he used are rated at, and get half of his rating as the eye can usually only distinguish between rate doubling or halfing. (ie: he used 10,000, so you get 5,000) Also make sure you get the proper resistors so that you dont blow your LEDs in a day. Also, your life will be easier if you get 12v LED's instead of 3.6-4.
Lets say I want to five under each seat and link it to a switch how would I go about wiring them with resistors?
Thanks
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From: NV
Rep Power: 811 That's gonna take forever. Let's say you want one blue led. You go to radioshack get a 2600mcd led with a forward voltage of 4v. I used a 560ohm resistor wired in, but I think you could go lower like 460 or something and still be fine. Too much resistance will dim the light output, too little will make it burn out faster.
power-->resistor--> + lead of led--> -lead of led to ground
power-->resistor--> + lead of led--> -lead of led to ground
I need TP for my bunghole
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From: OXNARD, CA. SoCal. "805", North of L.A.
Rep Power: 359 I read this and I'm more confused than ever:
I had to quote the post the images were white.
Originally Posted by PunkingCivic
I read this and I'm more confused than ever:
A Quick guide to wiring LED's in a circuit
LED's are quite different to light bulbs. Light bulbs are designed to work on a voltage, LED's can work on almost any sensible DC voltage if you have a correct value resistor fitted.
Resistors are relativley inexpensive and basically restricts the current passing throught the LED, as the LED's has no current limit itself. If you put an LED on a battery with no resistor it would be extremly bright for a fraction of a second before it blows.
To connect LED's into a circuit, it is advisable to know a little about Ohm's Law, a few basic formuals is all thats needed.
The figures you need to calculate the formula is the voltage you wish to work from, the current you wish to pass through the LED, and the forward voltage of the LED. The forward voltage can be found in the data sheet for that particular LED, it is the value of Vf, around 3.4V for White, different colours have different values.
Ohms law formula is V = I * R.
As we wish to calculate resistance it can be arranged to say R = V / I.
Connecting one LED and one resistor
For example lets say we have a 12V supply, and wish to run one Blue LED. We know the forward voltage Vf is 3.4V, and we wish to pass 20mA (0.020Amps) through the LED.
R = (12 - 3.4) / 0.020
R = 430 ohm resistor.
Connecting two LED and one resistor
As we have plenty of volts to drop accros the resistor we could add another LED in the circuit which would make the circuit more efficient. At the moment the resistor will get warm depending on power dissapation of that resistor, the reason for heat is that you are converting energy to heat which is wasted power. By using two LED's there re less volts to loose accros the resistor, it will still be the same current as passing throught one LED, in effect you are getting extra light as its two LED's, and less heat being generated.
R = (12 - 3.4 - 3.4) / 0.020
R = 260 ohm resistor.
Calculating resistor power
Power is measured in Watts, things like light bulbs are measure in Watts, most of the power is heat as a light bulbs is effectivly a resistor.
It is possible to calculate the power rating of the resistor required.
P = (V drop) * I
For one LED and one resistor at 12V
P = 0.172 watts
For two LEDs and one resistor at 12V
P = 0.104 watts.
Most of the time the rating of the resistor dosn't matter as they are usually 0.5watts which is plenty, but if you were to use surface mount resistor you would need to be aware.
Connecting LEDs in series and parallel
The above methods of connecting LED's was in series, if you wished to have many more LED's in the circuit you can basically multiply up the circuit across your power source to have as many LED's as you desire, this is where you may need to take care of the resistor heat, if you have many LED's in a small box with the resistors, all of it could get a little warm.
A Quick guide to wiring LED's in a circuit
LED's are quite different to light bulbs. Light bulbs are designed to work on a voltage, LED's can work on almost any sensible DC voltage if you have a correct value resistor fitted.
Resistors are relativley inexpensive and basically restricts the current passing throught the LED, as the LED's has no current limit itself. If you put an LED on a battery with no resistor it would be extremly bright for a fraction of a second before it blows.
To connect LED's into a circuit, it is advisable to know a little about Ohm's Law, a few basic formuals is all thats needed.
The figures you need to calculate the formula is the voltage you wish to work from, the current you wish to pass through the LED, and the forward voltage of the LED. The forward voltage can be found in the data sheet for that particular LED, it is the value of Vf, around 3.4V for White, different colours have different values.
Ohms law formula is V = I * R.
As we wish to calculate resistance it can be arranged to say R = V / I.
Connecting one LED and one resistor
For example lets say we have a 12V supply, and wish to run one Blue LED. We know the forward voltage Vf is 3.4V, and we wish to pass 20mA (0.020Amps) through the LED.
R = (12 - 3.4) / 0.020
R = 430 ohm resistor.
Connecting two LED and one resistor
As we have plenty of volts to drop accros the resistor we could add another LED in the circuit which would make the circuit more efficient. At the moment the resistor will get warm depending on power dissapation of that resistor, the reason for heat is that you are converting energy to heat which is wasted power. By using two LED's there re less volts to loose accros the resistor, it will still be the same current as passing throught one LED, in effect you are getting extra light as its two LED's, and less heat being generated.
R = (12 - 3.4 - 3.4) / 0.020
R = 260 ohm resistor.
Calculating resistor power
Power is measured in Watts, things like light bulbs are measure in Watts, most of the power is heat as a light bulbs is effectivly a resistor.
It is possible to calculate the power rating of the resistor required.
P = (V drop) * I
For one LED and one resistor at 12V
P = 0.172 watts
For two LEDs and one resistor at 12V
P = 0.104 watts.
Most of the time the rating of the resistor dosn't matter as they are usually 0.5watts which is plenty, but if you were to use surface mount resistor you would need to be aware.
Connecting LEDs in series and parallel
The above methods of connecting LED's was in series, if you wished to have many more LED's in the circuit you can basically multiply up the circuit across your power source to have as many LED's as you desire, this is where you may need to take care of the resistor heat, if you have many LED's in a small box with the resistors, all of it could get a little warm.
Last edited by PunkingCivic; Feb 15, 2005 at 09:09 AM.
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From: 20916, CA
Rep Power: 303 yo i realize this isn't really the forum nor thread to do this...but is there a downside to underpowering an LED aside from being dim?
Registered!!
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Rep Power: 0 led already last super long... so you probably won't notice the longer bulb life since it will probably already out last your car.
also have anyone actually killed a LED bulb thru high current so it doesn't light up any more?
'cause I tried it once, and the LED still lights up, although slightly dimmer and the light is less focus.
also have anyone actually killed a LED bulb thru high current so it doesn't light up any more?
'cause I tried it once, and the LED still lights up, although slightly dimmer and the light is less focus.
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From: NV
Rep Power: 811 oh yea. I forgot to put a resistor, and the thing got SUPER bright then fizzled out with some rainbow colors in a few seconds. Wouldn't work again obviously. 
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From: 20916, CA
Rep Power: 303 what wire would you splice the power to if you have a manual?...one of the plugs going to the dash buttons? i just want it to come on with the head/parking lights.
Joined: Sep 2002
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From: NV
Rep Power: 811 i guess not? Other than I need to fix it or put a fuse or something cause I'm screwed if there's power surge. It's all leds and el wire tho which doesn't use much power. Don't know what fuse to get for it.
Thread Starter
And Pimp I got the Juice 
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Rep Power: 290 Listen man,to Make the LED come on when ur head/parking lights come on is very simple...( If U have a auto..... there should be a white light already in the housing of ur shifter to make the Numbers Light up. Just snip that wire and connect led's.) BTW: I havn't been pulled over yet
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From: Largo/Seminole, FL
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Originally Posted by PunkingCivic
resistors? what kind. This like a foreign language to me. Help me uderstand.
Lets say I want to five under each seat and link it to a switch how would I go about wiring them with resistors?
Thanks
Lets say I want to five under each seat and link it to a switch how would I go about wiring them with resistors?
Thanks
Just for anyone that wants to know if you plan to do some LED work and wonder what resistor u need to use there are Calculators everywhere on the internet that tells you which one to use. Heres one i use often http://linear1.org/ckts/led.php
Marcus that looks good i might think about doing that. I have like 500 blue 5mm LEDs sitting in my shed. I bought 250 off some japenese guy on ebay for $10 never got them after like a month so i e-mailed him. Then the next day i got the first 250 so i e-mail the guy back and he had already send out another 250. So i got 500 of them for $10 shipped.
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From: Largo/Seminole, FL
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Originally Posted by 7th gen 4ever
can someone send me a message of how to get the top of the shifter trim and cover off please
Asahi nah i aint selling none of my LEDs...go to ebay and look around they are cheap from guys from Japan thats where i got mine from.
