Strategy for floor lamp

[peani]

Hello all,

I'm working on a prototype floor lamp and could use some suggestions and/or tips. I'm just beginning to wade through the world of LEDs so any help outlining this project would be welcome.

I'd like to achieve (eventually) brightness similar to a 60W bulb, using multiple simple emitters (5mm or similar) or multiple Luxeon-type emitters. The power source would be household current (110v AC) The lamp will be similar to your average incandescent or halogen floor uplight, i.e. there will be a translucent shade (glass or other material) open on the top. The emitters do not need to be clustered together (as if imitating a conventional bulb.) You could say this project falls somewhere between a fancy LED reading light and the InReTech 180-LED worklight.

So, if you were cobbling together a first prototype (you know, proof-of-concept, not necessarily achieve all performance targets, but enough to get you pumped up to do version 2...) how would you proceed, what components would you use?

I'm interested in particular in:

- compact power supply
- wiring arrangement (series, parallel, or combination) and resulting power needs.
- LED driving issues (no dimming necessary, just simple on/off)

Any thoughts are welcome!

[HaulinLow]

An admirable an challenging start to your membership here!!

I don't have the experience to help, but I want to welcome you to the forums and give your post a free bump to the top!!


I've seen some screw in led bulb replacements, but they are too expensive for me and not as much fun for you to build yourself.

Enjoy your project!

[yuandrew]

This thread may help you as well.

http://www.candlepowerforums.com/ubb...o=&fpart=1

I'm sure you can also find an old halogen uplight at a garage sale

[VidPro]

if you ask me just DC the AC and apply it. if you use a bridge rectifyer of high voltage, and huge high voltage caps, you dont need all the juice and heat wasted in a transformer.
then you just stick about 40 Luxes in it, in series, and some resistance to balance it out, and reduce the surge problem.

that would make it as usefull as a real 100W light, and would increase the efficiency longevity and reduced parts.

of course its entirely insane :-) but you did ask for ideas.
total cost about 400$ , and done correct, it could last 20+ years at high efficiency.

kinda like the worlds brightest Led Xmas bulbs, only cleaner input power.

[Ken_McE]

I suggest you put as much weight as possible down low in the base so it isn't tippy.

I would guess a 60 watt incan would give off about 900 lumens. That would equal about eleven or twelve 80 Lumen Luxeon III's, so the project is doable. I don't know how many 5 or 10 MMs that would be.

Luxeons will need radiators of some kind so they don't burn out. The whole top of the lamp might be a heat exchanger with a diffuser over it.

If you want to get fancy you could look into having some colored leds up there and mixing them to get any color light you like.

I have read of LEDs that have a strobe effect when run off household current, I'd want to avoid that, it makes some people naseuous. Or hey, you could do it adjustably on purpose and have a strobe light 8-)

I like 12 volts DC for current myself. Whatever you go with it should be something that divides neatly between your LEDs so you can avoid power-sapping resistors.

For esthetics, consider a ring of 5 MM LEDs mounted in a circle facing out to the sides. There are many lamps that do variations on the lots of little dots of light theme. If you really want to get fancy they could be changable color leds and you could set them seperately from the main light.