# Newbie needing help lighting 5000 LEDs

Discussion in 'The Projects Forum' started by pauldotharrington, May 8, 2010.

1. ### pauldotharrington Thread Starter New Member

May 8, 2010
3
0
Hi there,
I am starting a project and i need a bit of help with the planning.
I have worked with LEDs but never at this scale. (I have worked with maybe 50max). To be fair im a complete newbie to this.

My plan is to light 5000 white LEDs.

I would ideally like to run this off as little plugs a possible, without blowing the power in the house. I was thinking of running them in parallel but thats because i found the easiest way and if one goes, the rest will still be working which is very important.

Any help you can give me on how to get this project on the way would be very much appreciated.

Paul

2. ### SgtWookie Expert

Jul 17, 2007
22,194
1,764
What is their typical Vf @ current rating?

Trying to run them all in parallel will be kind of messy, and you'll need one current limiting resistor per LED. If you run them in series strings, you only need one resistor per string.

This power supply:
http://www.mpja.com/email/05-04-10a.asp?r=%%ref%%&s=27
could supply enough current to light 1,950 LEDs that were rated for 3.6Vf @ 20mA, in 325 strings of 6 LEDs and one 120 Ohm resistor per string.

You could get three of those supplies, and just run 278 strings of six LEDs per supply; that would be better as the supplies would not be operating at 100% of their rating; just about 86%.

3. ### Bychon Member

Mar 12, 2010
469
41
Start by revealing which country you live in so we can know where you'll get parts.
Next, decide on a LED and find out how much voltage it needs.
Decide how much current you will give it.
Reveal what voltage is available in your house.

As long as we don't know the voltage, the LED's, the current, or where you are, we have nothing to work with except that you will need at least 10,000 connections.

4. ### retched AAC Fanatic!

Dec 5, 2009
5,201
315
Answers to bychons questions would be important.

Are you making a shape(besides a rectangle)

Are you trying to make a design or art piece?

If not, and you just want to make a big 70x70 (plus 100) square, you may be better off ordering 10 by 10 panels. This would cut down on the amount of soldering and give you a huge advantage against the accidental wrong way LED.

Are you trying to make a video wall, or just a real big light?

5. ### pauldotharrington Thread Starter New Member

May 8, 2010
3
0
Many thanks with your immediate responses and sorry for the delay.
I am living in Canada (in Montreal).

The LEDs i intend to get are " WLD : 465-470 NM, IV: 10000-12000 MCD, VF: 3.2 -3.4V "
I am assuming the voltage in my house is 120/240V

I am not sure what amount of current to give it. A complete newbie

What I am making is an art piece that is 100x50 LED dimension about 15cm apart.
I am essentially making a big light.

6. ### SgtWookie Expert

Jul 17, 2007
22,194
1,764
Don't purchase them unless the seller can provide a datasheet from the manufacturer.

7. ### Audioguru AAC Fanatic!

Dec 20, 2007
9,459
915
Since they have a brightness rating as high as 10,000 to 12,000 MCD then I suspect that they are not bright but are focussed in a very narrow beam (5 degrees) to appear bright when on axis. Then off axis they will barely be seen.

I think you should use LEDs that have a wide beam. Most of my "wide angle" LEDs are 40 degrees. My solar garden lights use LEDs with an angle of 120 degrees.

8. ### Bychon Member

Mar 12, 2010
469
41
That's a lot to think about. You are deciding the viewing angle...the width of the area people can stand in and see properly when you pick the angle of an LED. I will not be surprised if you have to ponder this for a while.

9. ### retched AAC Fanatic!

Dec 5, 2009
5,201
315
If the piece is going to be displayed at the end of a hallway, narrow angle LEDs will be fine. If there is a possibility that it will be viewed at an angle other than STRAIGHT on, I would use a wider angle LED. 15deg are no good for side viewing, and the "super brights" are typically very narrow to "appear" brighter.

10. ### SgtWookie Expert

Jul 17, 2007
22,194
1,764
All good points - but another point to consider is that super-bright LEDs can cause permanent eye damage if people stare at them for a period of time. The really narrowly focused LEDs are particularly bad about that. Having diffused or wide-angle LEDs will be much easier on your viewer's eyes.

11. ### pauldotharrington Thread Starter New Member

May 8, 2010
3
0
Oh my god, that is alot to think about. Many many thanks all your responses. I'm going to have a little think now. see the best way to do this.

Ill be back