Help designing under cabinet task light w/LUXEON III

Hi,
Hope someone can help. I need to light an approx 7"X7" area on a table at a distance from table surface to LEDS or about 10"-12". The LED's will be spaced about 8" apart from each other shining down at the table surface.

I really need to keep the cost down as much as possible but I do need a fairly even and bright illumination across this 7"X7" area.

My first though was to purchase 2 Invova x5's, pop the lamps out using the "ice" method I read about on this site and mount those but after a bit of expermenting, I think using two Luxeon III stars would be a more cost effective way to go.

Here is where I could use some help from the experts. If I were to use 2 Luxeons III's, which collimator lenses would work best? I think the FHS-HWB1-LB01-H($8 each) on the Luxeon star site would be the best choice? Anyone have any experience using and mounting these? ANy tips? tips on heatsink?

Also, what would the best way to power these two up. I need to do it using a 12v dc source. Which driver would you recommend keping cost in mind? I saw on ebay someone selling a driver that makes the lamps variable which would be fantastic for my appliction rather then simply on/off. Anyone have any schematics to build a variable driver or should I just spend the $10 on ebay for the kit? Do the variable drivers would good on the the luxeon III?

Any advice to do what I need to do or the best way to go about it would greatly be appreciated! I am open to any ideas!

Love this Forum.
Thanks!

Wade


PS Sorry for all the questions!

Does anyone have experience dimming a luxeon III?

I can only help recommend the driver.

Based upon your conditions of using 2x 3W and a 12V power source. You will need a step down converter. They can be found at taskled.com or theledguy.com (Sandwich Shop).

If you know the exact drive level then you can go with a CCxW or DownBoy to save $$$. If you want variable output (dimming control) you could use an nFlex or uFlex for the job.

As far as optics/reflector, it's pretty hard to make this suggestion since it more of a "personal" taste and how the light will interact with your 7"x7" surface. If it were me, I would start out with IMS SO17XA reflector then NX05, Fraen and Carclo optics since the distance is so short.

Best of luck with you project and keep up update.

The most even lighting will come from "no " reflector at all. The only purpose of a reflector at that distance would be essentially as an eye shield. If you use a reflector, make it a small one.

Taskled is a great place for 12 v supplied control boards. In fact, George makes a very nice pre-built setup for 12 volt applications. There are even some reflectors that might do what you need, which are very smooth floods.

My little under cabinet lighting project (still under development)

The LED's are 4 TWOK LuxIII's emitters no optic or reflectors, wired in series, the controller is a nFlex it runs off 16 AA's, yeah I know

The heat sinks are flat stock aluminum 9 x 1 3/4 x 1/4 held in place by double sided tape.

As HarryN suggested you will get more even light without a reflector or optic, my set up with 4 LED's covers the whole bar 9' x 3' with soft side spill into the room.

This pic was made on high with the nFlex set to the 1000mA level, in person it is brighter and the spill into the room is better, I'm just not very good with cameras


For your area 7" x 7" you may be able to get by with one LuxV LED but either way will be OK.

The nFlex driver will work just fine with 1 LuxV or 2 LuxIII LED's and your 12V power source just make sure the mA output is high enough for the drive level you select. I set mine 1000mA so it can be used for back up lighting and reading when the power is out but other than that level 1 to 3 is bright enough at that drive level for general use.

Another nice thing about the nFlex is you control everything with one momentary button programming, on/off and the brightness level.

Later
Kelly

Nice job Kelly

thats cool kelly