LED wiring

BlueBall · Nov 19, 2004

I am looking to wire about 40 LEDs in a row (in parallel) and I was wondering if I need to put any resistors along the row, or if the single 400R at the beginning of the 12V row is enough?

Will voltage drop (eight feet = 40 x 3mm LEDs @ 2" apart) make the first and the last LED have a different brightness?

OR ... will a 'wall wart' supplying 3.6VDC with approx 500ma be enough (without the 400R)

recommendations please ....

I will post a pic when I am done ... I am lighting behind 8" glass blocks that surrounds a jacuzzi. I am making flexible strips of bright LEDs that slide into clear acrylic tubing behind the glass. Custom design.

I know they make X-mas light 'ropes' but the light is yellowish. Too bad because they are $6 .. LOL

BlueBall · Nov 19, 2004

this place used to be full of knowledge ... anyone?

BlueBall · Nov 19, 2004

DaMobster · Nov 19, 2004

this would probably be better off in the alternative mod section since they know a lot about this sort of project.

DaWiper · Nov 19, 2004

Here is what I would try:
I would buy 40 pieces 5V ultrabright sunbeam leds and hook them all up in parallel.
These leds are extremly bright and are designed to be hooked directly to a 5v source without any resistor.

As I said "This is what I would try". I have no clue if it would actually work, but I belive it would... They each draw 6-12.6 mA depending on what color you choose. Worst case scenario=40x12.6(red led)=506mA.... Someone correct me If my calculations are wrong.

JigPu · Nov 19, 2004

Since you're wiriring them in parallel, placing a single resistor right after the battery (or whatever your powersource will be) will work fine. Also, because of them being wired in parallel, each LED will be equaly bright all down the chain. The only voltage drop that would cause the "end" LEDs to be dimmer should come directly from the wires.... Which at 0.01 ohms/foot (for 20 gague copper) would need a LOT more than 8 feet to make any difference

I'm not sure about the wall wart, though I'd be willing to bet it'd work fine provided they'll work with 3V.

JigPu

BlueBall · Nov 20, 2004

Thanks for the great info! You answered my question.

I ran out and bought this 5V 3A switchable power supply. I also bought resistors (82R). The entire circuit will be on a motion sensor. I also bought a humidity sensing exhaust fan.

Now I just need some bulk LEDs ... back to eBay ...

Thanks again .. I'll post a pic in a couple weeks :>

Keiron · Nov 20, 2004

I believe there is a website that sells LED's from Hong Kong for like $1 per hundred or some excessivly low price. I'll see if I can track it down for ya.

BlueBall · Jan 16, 2005

Heres a pic of the lighting ....

I still need to get a shot of my led strands that are between the glass blocks and the back wall.

BlueBall · Jan 16, 2005

This is just another angle ...

BlueBall · Jan 16, 2005

Click Here for more pictures

Dc5e · Jan 16, 2005

whoa! very nice. Although instead of LED's you could have used other methods of lighting up the base (incadescent lights or other stuff with a blue filter). Must of took you quite a long time to wire up all those LED's too.

BlueBall · Jan 16, 2005

Dc5e said:
whoa! very nice. Although instead of LED's you could have used other methods of lighting up the base (incadescent lights or other stuff with a blue filter). Must of took you quite a long time to wire up all those LED's too.

The base has a 4" flourescent fixture built in as well. That is what you see in the picture. The LEDs are there as well. They cannot be seen individually behind the white diffuser exept for the blue LEDs.

What else turned out to be really cool was the tile ledge was made of cultured marble and quartz ... sliced and polished ... the light shines up through the glass blocks illuminates the quartz embedded in the marble.

I'll add picks soon ... I just need to attach the cabinet doors and its basically done.

BlueBall · Jan 16, 2005

I learned a few things I'd like to share.

All power supplies are NOT created equal. Unfortunately, they do not label them properly.

Regulated power supply means there is exactly the labeled output. :thup:

Unregulated power supply means there is MORE than the labeled output
:bang head

The only way to tell them apart is to use a voltmeter.

I decided to make my own power supply from an educational kit.

I should learn alot from this.

BlueBall · Jan 16, 2005

Heres the product description

BlueBall · Jan 17, 2005

BlueBall · Jan 17, 2005

pic with flash

Captain Slug · Jan 17, 2005

Cheap LED source mentioned earlier in thread
http://www.stores.ebay.com/store=70930951

BlueBall · Jan 17, 2005

Check this LED eBay store ... 100 LEDs @ 5000mcd for $0.99 plus $10 S+H
http://stores.ebay.com/hktaiyuen-LED-store_W0QQsspagenameZl2QQtZkm

That link you gave has MUCH brighter LEDs.

I have used 20,000mcd and 5,000mcd LEDs ... I can't say they are 4X brighter, however, they are brighter.

BlueBall · Jan 30, 2005

Heres a new pic of my custom made low voltage control center.

LED wiring

Member

Member

Member

Member

Image Compare Man

Inactive Pokémon Moderator

Member

Attachments

Member

Member

Attachments

Member

Attachments

Member

Member

Member

Member

Attachments

Member

Attachments

Member

Attachments

Member

Attachments

Helpful Senior Member

Member

Member

Attachments

Similar threads