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igatenby
05-27-2005, 02:32 AM
Phew .....

I've been experimenting with lights....

I just bought a whole heap of different LEDs and a couple of cold cathode flouros (100mm and 300mm).

My high point, dollarwise, is curently at $A110 ($US83) for 2 x 3 watt Luxeon LEDs complete with lenses and driver kit - but without the necesary heatsinks. I'll report back on these when I get the driver kit built and some heatsinks on. I've got a sneaking suspicion that these will push out some serious candlepower. The specs rate them at 80 lumens (against a 240V 100W globe which has about 1200 lumens).

Funny thing is, that so far the best light output is from the cheapest thing, at $A8.95 ($US6.70), which is a PCB with 3 x high intensity LEDs on it, drawin about 60mA. I've paid $A40 for multi LED bulbs that plug into halogen fittings that don't push out as much light.

The cold cathode fluoros don't have enough light output and at around $US30 each, I don't think I want to run 20 of them to get the lighting effect I want in the cabin.

What started this is the broken lenses in my 67 year old navigation lights. I can epoxy the glass lenses back together, but heat from an incandescent bulb will cause problems. I'm planning on building my own LED setup with 5mm high intensity LEDs clumped together so that the light spreads appropriately. LEDs typically have a narrow light beam.... hence the need for a multi LED setup, but the available bulbs all orientation in one direction.

The next driver of curiosity is the way we have rebuilt the cabin on Grantala. We kept the original cabin roof and beams but replaced the cabin sides - so there is a join, which we strengthened with a shelf (about 1.5 x 3.5) under the beams, which we are covering with a pelmet - which will have curtain rails behind it. The idea of pelmet lighting came up, but there are about 13 or 14 beams in the main cabin (salon) - so about 28 lights needed. This would be out of the question with incandescants - hence the LED research.

I'd rather spend a couple of thou now on decent LED lighting that my 80W solar panel can service than stuffing around having to run the genset at night.

Has anyone done anything like an LED setup on their boat?

Ian

Dan McCosh
05-27-2005, 06:26 AM
I have a single cabin light, which is nice while sailing at night to keep some light on down below. I keep looking at running lights--both for low current drain and durability, but they still seem too expensive. The color isn't too pleasant for general cabin lighting, in my opinion.

Frank Wentzel
05-27-2005, 10:37 AM
Ian

Please post all you can or give us links on leds and driver circuits. I want to use leds for most of my lighting. I was thinking about putting several individual leds in various pieces of molding about the boat so as to have a virtually invisible/sourceless lighting system.

For navigation lights; I was wondering about rapid pulse high current drivers that would have an average current within the leds normal operating parameters. I don't know how to design the necessary pulse/oscillator circuits but I was hoping this would fool the eye into seeing them as being brighter than they are - especially if the pulse rate was such that they would appear to have a slight flicker. Maybe this would make them stand out in a field of uniform light sources.

/// Frank ///

Dan
As to the comment about color for interior lighting: I was going to try using some yellow leds mixed in with the whites to mute the actinic color of white leds.

P.I. Stazzer-Newt
05-27-2005, 10:52 AM
I hate the idea of a heatsink - that is wasted power - there is almost always a more elegant way of doing it.

paladin
05-27-2005, 12:14 PM
heat is wasted energy.....
The led's can be series strung with a current regulator chip to provide constant voltage and fixed current through the leds.....and I dunno where you are getting your parts but that is WAY too much money.
Also...read all specs carefully...you can buy the led's with different aperatures..or light exit angles so the light pattern can be broad or narrow...or something in between, as you wish...

Gerald
05-27-2005, 12:18 PM
I have done some tests with LED's. The prices you have stated don't relate to what I have been doing. The LED's I have purchased are probably used for instrument panels? The red bulbs cost 6 US cents and the white cost 80 US cents. Since it was a test I used the red ones. Instead of hooking a resistor in series I just hooked 7 red bulbs in series. The are rated for 1.5 volts. However, they didn't burn out after twenty hours of test at 3 volts. I ran the 7 bulbs for a month on a junk VW bug car battery and still had a nice bright lite.
I will be installing red light in the boats bedrooms and near the navigation table. According to what I have been told, red light will not screw up the focus of your eyes at night? You can read something and still see the oncoming barge.
I am interested in hearing more about peoples experience with LED's.
Gerald

trull
05-27-2005, 01:33 PM
http://www.theledlight.com/

Meerkat
05-27-2005, 05:19 PM
Originally posted by trull:
http://www.theledlight.com/Even better: http://ledsupply.com/index.html

A 2-Cell 1W MicroPuck LED driver, soldered with a white Luxeon I Star LED.

The 2-Cell 1W MicroPuck (2009) was designed to power a single Luxeon I, or strings of 5mm (T 1-3/4) LEDs (see app. note) efficiently and with stability. This driver has been designed to provide maximum illumination to the LED while still mimicking the light dropoff of an incandescent bulb, which dims as the batteries are used up. Unlike an incandescent bulb, the driver's current consumption drops at very low voltages, allowing usable light to be produced much longer than conventional flashlights. Battery recovery (after the flashlight has been off) is also improved.

Kit Contains:
1 02009 MicroPuck 1W LED Driver Module
1 LXHL-MW1D Luxeon I Star White LED

For detailed product specifications and example circuits, please refer to the product datasheets.
MicroPuck Product Datasheet
Lumileds Luxeon Star Datasheet

Luxeon is a tradmark of Lumileds Lighting
MicroPuck is a trademark of LEDdynamics

Availability: Usually ships the next business day.

MicroPuck /Luxeon I Kit
KIT001 $19.99

[ 05-27-2005, 05:23 PM: Message edited by: Meerkat ]

Gerald
05-27-2005, 09:29 PM
Here is a site that sells the LED's that I have been using. Looks like I have been paying more than 300 percent markup.
http://www.besthongkong.com/modules.php?name=catalog&file=index&cPath=2_9
Gerald

JTA
05-28-2005, 06:31 AM
Try here

Digi-Key (http://digi-key.com/)

Jack