New to site not sure this were to post this. Led's for ac powered model railroading, to replace incandescent bulbs.  Voltage to track varies from 5 to 17 volts AC.  Leds will light up, but what is it doing to them. They do not pop like a flash bulb at top voltage. I've rectified some to dc voltage for lights in cars, the variable voltage seems to power them. Ideally a circuit that put out a constant 3.2 DC volts, with a variable 5 to 17 volt AC input.  Or maybe would a constant 3.2 volt AC out would function? I found that with HO DCC control, a white led with a 1k resistor will function, have not ran them for more than few hours though. Prewired rectified leds go for around $3.00  each, 5 passenger cars, 2 bulbs each, gets pricey with 4 sets of cars. Surly someone has gone through this.

Posted by 31cssinc 4 years ago | last reply 4 years ago

Resisters and LEDs? Answered

I was wondering when i wire LEDs together does there have to be a resister for every LED? (i making an arc reactor with 7 LEDs)

Asked by Emsaid 9 years ago | last reply 4 years ago

help to build a led light sheet with 100 3mm leds

I Need help to build a led light sheet with 100 3mm LEDs they are 3.5v LEDs I have never worked with LEDs before or resistors so please keep it in simple terms. the idea is to use a 12v battery and reduce it to 3.5v supply any ideas comments are appreciated

Posted by YARTZ 10 years ago | last reply 10 years ago

what's an easy on/off switch for an LED light?

What's an easy on/off switch for an LED light, when using a simple battery and a single LED?

Asked by buckcomm 6 years ago | last reply 6 years ago

how to wire led?


Asked by morgie 8 years ago | last reply 8 years ago

my leds not work Answered

Is it possible to run 5mm white(3.3v each) 6 led series by 5v adapter without any rasister????

Asked by neelpal 1 year ago | last reply 1 year ago

how to wire 10 leds in parallele with resistor and battery? please? Answered

10 green leds 2.4 max volts

Asked by jconner3 7 years ago | last reply 7 years ago

I have 32 Red LEDs and 2 Green LEDs, what should i do with them?

I've had these LEDs layn around for a while and i can't think of what i should do with them

Asked by Inventor Pro 8 years ago | last reply 8 years ago

LEDs strips

who can help me, i need to make a very long LED strip, and i dont know how to do it, thnx for yor help :)

Posted by eyoung1 7 years ago | last reply 7 years ago

can i get circuit of 90 white leds @ 12volts 7 Ah battery?

led circiuts

Asked by arbp 8 years ago | last reply 8 years ago

were could i buy leds online cheap?

Asked by mb inventor 6 years ago | last reply 6 years ago

How do i wire LEDS to a 12v supply

I've got some LED lights that used to work of 6v a battery, 60 LEDs per light, I want to convert them to use 120 LEDs to run of a 12v system, i've got 1,5ohms and 2,9ohm resistors that came with the lights, how do i wire them to work? Might want to put 180 LEDs per light if it works, i've already burned 120 LEDs

Asked by fjchorn 7 years ago | last reply 7 years ago

5mm led problem

I want to make a 5mm white led  series and run it by 5v power supply so i want to use 1 resistor is it possible?????

Asked by dey suamn 11 months ago | last reply 11 months ago

how many leds can run of 3 AAA baterys?

Asked by mb inventor 6 years ago | last reply 6 years ago

12 volt leds

I work at a custom motorcycle shop and use led lights in our fenders. I'm having trouble finding a constant supplier of 1,2,3, sequenced led lights for run light,turn,and brake. Any one can help that would be awesome!

Posted by cbarr600 5 years ago | last reply 5 years ago

What kind of LED is this? And how to use this using DC or AC?

Good day everyone. I'm new to Instructables and I'm searching for LED projects. I have destroyed our old CD player which have so many LEDs in it, and found out they are not the conventional circle LEDs. They are rectangle-shaped. I remembered that these LEDs light different colors, but I'm not sure. I want to use it in my first project using LEDs but I don't know how to use them, or are they RGB LEDs. I also cannot  test it because I haven't bought a soldering iron to melt the solder and remove the LED. Please help me. Thanks in advance. I have pictures to show the LEDs I'm referring to.

Asked by CarlGemarino 4 years ago | last reply 4 years ago

problem with 5mm leds Answered

I make a 5mm(3.3v) white  6 led series and run it by 5v adapter without any resistor but after running feu hours 1 or 2 leds slowly lost it's brightness and then it's off i can't understand what is the problem please help.....

Asked by neelpal 1 year ago | last reply 1 year ago

how do i get a multicolor led to change colors.?

I bought a new multi color led but i cant get it to change colors all at once

Asked by gamefreak0723 9 years ago | last reply 9 years ago

trying to dim several groups of LEDs through 12/2 mc but getting to much voltage loss.

Dim LEDs over 100 ft 12v source through 12/2 mc

Asked by 9 years ago | last reply 9 years ago

What are good materials and/or techniques I can use to diffuse or "spread" a LED's Light? Answered

I wanted to do some cool things with LEDs but i want to diffuse the LED's light in order to light up the biggest amount of area while using the least possible amount of LEDs and electricity.

Asked by Mrpnut 9 years ago | last reply 9 years ago

If i cut this 30cm LED strip that written 12V, how much will voltage will iit be per 2 LED's?

1) can i use 9V battery to it?  2} Its a long strip that written 12v every 2 led's, so if i cut, How much Voltage should i apply to it?

Asked by miraheng 2 years ago | last reply 2 years ago

How can I increase the maximum LED's in this LED chasing circuit?

I need to drive 112 LED's from this chasing circuit and it is limited to 48 LED's.  I'm hoping some minor changes to the circuit will allow for this.  I would appreciate any help since I am a novice in this area. Attached is the link to the chasing kit and the manual with circuit diagrams.   Thank you in advance for any assistance.  http://www.rainbowkits.com/kits/cl-1p.html http://www.rainbowkits.com/kits/instructions/CL-2.pdf

Asked by GrimaC 2 years ago | last reply 2 years ago

RGB led help? Answered

So i picked up an RGB led at radioshack and when i got home, instead of having 2 pins like normal leds, or 4 like some RGB leds, it had 3 pins, and im not sure what to do. I mixed and matched the  pins with ground and positive wires until it lit up, but it just ran through a cycle of changing colors then stopped and doesnt light up again unless i disconnect the led and connect it again. And as far as i know, the one pin not used in this cycle doesnt do anything. So is this all the led does or is there more? P.S. i wasnt using a potentiometer or anything, just connecting it to power.

Asked by texpert 7 years ago | last reply 7 years ago

Turn on LEDs one after another?

Hi, I want to make a circuit where I can connect 5-10 LEDs. When I turn it on first LED should turn on for a moment and then turn off, after that the next LED does the same and so on. So that it has an appearance of 'flowing light' throughout the circuit. The problem is that I don't know the name of this circuit or anything so I am unable to search anything on the internet regarding it. Any help would be much appreciated. Regards Tehreem

Asked by tfatima1 4 years ago | last reply 4 years ago

different voltages for leds?

Leds on ebay,at different online shops and,found in old electronics.can any led work with say, 12 volt car power,[dc, with the appropiate resistors]disconnect it and hook it up to ac house[again,with the appropiate resistors]current?should i look for certain voltages sources when buying or just strive for the voltage the led calls for?also,is 12 volt dc car power the same as 12 volt computer power?the fans and such on computers [as far as i can tell]run on 12 volts.might seem like a silly question,but then i'm REALLY not very conversant with all this led tech.in other words,can i run an led off any[ac or dc]current as long as i use the correct resistor?thanks for schooling me on this.i'll be forever gratefull

Asked by frankentrike 8 years ago | last reply 8 years ago

tell me about power rating and voltage rating of a led ?

Asked by achanta 7 years ago | last reply 7 years ago

Where can i get bulk 8mm leds?

Really any size above 7mm will do but i need 36 0f them to run on around 4 volts

Asked by theboygenius 6 years ago | last reply 6 years ago

LED wiring standards?

Making a wooden rangehood for my wife for our annivesary, and I want to use LEDs  for the light source. I wan to use 3 banks of 30 lights in each 4X8" oval space, and from what I have read it would seem to better to wire each set in parallel. My question is, do I need to put a resistor on each LED to adjust the voltage to the proper amount, or (since it is wired parallel) will one work for all?

Asked by Billwelder 8 years ago | last reply 8 years ago

how do you wire led's in a line circut with one on off switch. very new to this.?

I want to make a sign for a play that can be turned off for other scenes. I want to wire led's together in one circuit with one power source. (how much power and what type would I need?)

Asked by bluefly1215 9 years ago | last reply 9 years ago

how do i connect 2 sets of leds that have different volts and mA's?

Ok one set reads current: 20mA suppply: 3.2V and the other reads current: 25mA supply: 3.3V

Asked by guy86 9 years ago | last reply 9 years ago

led to music? Answered

Ok... i have been looking into this for the past month tried to use a TIP31 transistor to make my led light strips flash to music in my car by using my sub amplifier as an audio out source...... and it would not work so i was wondering if you someone could help me out to make a box that would allow for audio in from my amplifier that would have a circuit that would perform the task of making my led light strips flash to my music. thanks. 

Asked by dallyski 6 years ago | last reply 6 years ago

LED lights

My name is Cindy,  our company produce LED components and LED lights in many appication. If everybody need such products, don't hesitate to contact with me. International Business Department Lucky Light Electronics (Asia) Co., Ltd Add:6th Industrial Park,Nanlian,Longgang District,Shenzhen, China. P.C: 518116 MSN: leds14@hotmail.com Skype: luckylightled E-mail: led8@luckylight.cn Tel: +86 755 8461 3005 Fax:+86 755 8461 3126 Website: www.luckylightled.com

Posted by cindy2819 8 years ago | last reply 8 years ago

I need a LED grow lamp that has a slider (like a dj deck) that mixes red to blue to white. ?

Possibly with around 100 bulbs. Maybe using those 4 pin RGB leds? Could someone build something like this? I want to be able to change from vegetative cycle to flowering cycle using just the one lamp setup.

Asked by 9 years ago | last reply 8 years ago

do you need to do anything special to hook up leds into a wall socket lamp?

I'm working on building a lamp out of a guitar I'm using fiber optic cable as the strings and want to put leds under them to make them light up the lamps going to be plugged into a wall socket. what is the best way to do this.

Asked by rabbitflinger 9 years ago | last reply 9 years ago

Can I run an LED at a high voltage? Answered

I want to create a discharge indicator for a capacitor bank. I planned to do this with a simple switch-resistor-LED setup. My LED has a forward voltage rating (as well as max reverse), and it has a max current rating. My capacitor bank is 330V, so once I calculated the resistance I needed for the 20mA I plan to use, I created a board of resistors that will give the required current and dissipate >10W.  My 20mA is 10mA less than my LED's max current rating. Its forward voltage is 2.8V. Even though I have proper current levels and power dissipation, will the 330V burn out the LED? I didn't think it would, but I wanted to look around and make sure. I couldn't find any definite answers. Thanks!

Asked by TheMike25 5 years ago | last reply 5 years ago

41 LED Flasher Circuit using 555 IC

Hello from Scotland   Being costume and armour builder but being new to the electronics world I noticed this build using 41 led lights this would be perfect to compliment a build i'm currently working on my question is this do you have some sort of step by step guide to this build as I really think this will work my understanding of electronics is very very basic I can rig some leds together that's about it   Any help would be fantastic

Asked by TattooedJudge 2 years ago | last reply 2 years ago

I'm seriously jazzed about making LED toys n such for my kids. I have no idea where to start with basic electronics.

I want to learn basic circuits, soldering etc. to make LED toys and whatnots for my boys. This would be a fun thing to learn and share in the coming winter months when we're stuck indoors. Can someone recommend a good book or guide? Thanks in advance!

Asked by FyreAntz 8 years ago | last reply 8 years ago

Concerning "pirahna" 5mm superflux leds.?

 would appreciate some info regarding the  1/2 W 5mm "pirahna" superflux leds.  started using them and think they are great.  do they need any other regulating component other than a resistor to keep them running  safely?  how do they hold up over time? i just need to use one or two in my projects (powered by a  9v unregulated wall wart).   thanks!

Asked by lightartist1 8 years ago | last reply 8 years ago

Is a 1 ohm resistor really needed? Answered

I will be making an LED display. After calculating using the online calculator, I am told that I will need 1 ohm resistors for my series of LEDs. I am thinking that 1 ohm is really not a lot and if I can skip it. Thanks!!

Asked by stella_7277 8 years ago | last reply 8 years ago

with the LED balloons, you get 2 watch batteries, but with a bigger battery, it won't light up. Why?

Inside the little box that lights up the balloon are 2 watch batteries and an LED with two prongs, the 2 batteries are stacked so the negative terminal is on 1 prong, and the positive terminal is on the other i tried to use a bigger battery but it still won't light up. Anyone know why? or if there is another way to make it light up with a bigger battery?

Asked by IamGOD Biotches 6 years ago | last reply 6 years ago

Any ideas of how to change the colour of diffused LEDs, can they be painted or dyed in any way?

I'm currently doing a project involving LEDs and want to be able to get the colour of them to match into my colour pallette, which is quite metallic and pastel, so I was wondering if there is any way of taking white LEDs and then changing the colour. Would something like glass paint be ok, or any kinds of dye that people could suggest? Any hints, tips or suggestions would be greatly appreciated. Thanks :)

Asked by misfitforhim 6 years ago | last reply 6 years ago

saw on you tube a custom led tail lights with a cool lighting program that was orignal. can someone help me?

I just purchased a 2012 dodge challenger and saw on you tube a custom led tail lights with a cool lighting program that was orignal. Can anyone help me or steer me in the right direction to either show me how to build one or know someone who can make it. thanks. http://youtu.be/YQ6liqCtKgg http://youtu.be/U84jSrVN_AI

Asked by georgesiete 6 years ago | last reply 6 years ago

Which is the best online store selling electrical components i.e LEDs,resistors ect(uk only)?

I would like to make some of the electical projects especially LED stuff, but not sure where is best to order my parts? i dont know exactley what parts yet,just need ageneral allround electrical online supplier. thanks

Asked by 9 years ago | last reply 8 years ago