|Topic Review (Newest First)|
|01-19-2008 01:15 PM|
"Enlighten someone!" heh...
We have small C-shaped flourescents (5 watt, I believe) as bunk reading lights that are so nice that I wouldn't change them for LEDs, given the limited time they typically are on. I can see switching the 10 W incandescent bulkhead lights, however, as they are behind little shades and a "warm LED cluster" on a standard bayonet mount would not likely change the "perception" of how the light is used (to illuminate the dinner table), but would save a lot of amps, as these lights are on four or five hours per night.
We need spots for the head and the galley, and LEDs seem the way to go here. I have a nasty bluish single LED in the icebox, but that is actually quite sufficient to identify what I want in a hurry, at a tiny draw. I've actually left this one on for days at a time by mistake, and the draw doesn't register if the weather's heated up a bit, thereby warming the batteries.
|01-18-2008 04:35 PM|
General area lighting and LED's
For a long time I dreamed of being able to light up the interior of our boat and go for night after night without hurting the battery levels. I felt that LEDS were going to advance and make this possible. Unfortunately for interior area lighting they simply do not produce light in a manner that makes this possible. I can go quite a few days without recharging with the engine using a different lighting technology. BTW I have two young daughters that use lots of lights and insist on sleeping with a night light on. Any time I'm below I always seem to be turning off the lights behind them.
I hope everyone will forgive my murdering of lighting terminology. Think of a lumen as a volume of light. LED's do not produce as many lumens per watt as do compact flourescent bulbs (CFL). So for light volume per watt CFL is way more efficient than LEDS. There is another technology cold cathode ray flourescent that is even more efficient for interior lighting applications. This is what we currently use. I purchased a number of bulbs from Glenergy in Canada. They have worked well and kept me from fretting about the amps. I did kind of hurt one - cracked it's mounting base but it has been going strong with only a black tape patch. They have a one watt version that is acceptable to my daughters for night long use. An eight hour burn is only .75 amps! For general area lighting we use 5 watt bulbs and one is enough to light up the main cabin in our 30' sloop. With two on you can read anywhere in the cabin.
LED's can work well in nav lights. If you are retrofitting your fixtures, you just need to fit the most bulb possible into your old fixture. Be sure to get colored bulbs for red and green applications. Otherwise your colored lenses will stifle the light output. Your anchor light is a biggie cause you often run it from dusk to dawn. Leds make good spot lighting for task lights, etc. on the inside. And I simply will not own a non-led flashlight any longer.
Hopefully our experience will enlighten someone.
|01-18-2008 03:44 PM|
FWIW, the "good" LEDs are units like the Lumileds Luxeon K2, which at one time was the light source for the Orca Green Marine LED nav lights. These LEDs require a constant current control and GOOD heat sinking. The constant current controller is cheap. The heat sinking is critical, as LED lifetime is directly related to the junction temperature of the LED. The major reason for the cheaper, encapsulated LEDs (the type that require several dozen to produce intense light) having a short lifetime is that they have no way of shedding heat. The premium LEDs like the ones used by OCM have a dedicated thermal connection and do a much better job of keeping the LED cool.
Originally Posted by hellosailor View Post
|01-18-2008 01:39 PM|
LEDs, like other solid-state devices, only have a long life when properly fabricated and matched to the installation.
If you take a look at the LED tail lights commonly used on trucks and busses, they are a prime example of cheap LEDs. One or two dozen cheap LEDs in each unit, three or four burn out within the year but that's OK because the unit itself is still bright enough--and cheap. Using better LEDs and adding protection to the circuit would raise the cost tenfold, so cheap and sloppy wins.
OTOH the LEDs in a mercedes or Cadillac taillights supposedly raise the cost of the array to $700 factory net. They're designed to go 5-10 years without any burnouts.
Prime LEDs, properly protected, have a life near 100,000 hours. Adding protection costs more than an LED does.
Kind of like sails: They all work, some just work better and longer than others.
|01-18-2008 11:50 AM|
Just talked to a couple of colleagues who are using LED replacement bulbs in their nav lights. One is happy so far, the other has three LEDs fail in the bulb, the others working after one year. - The LEDs might have a long life, but the bit of electronics and wiring inside the bulb may not.
They recommended "wait a while" for the technology to improve and the prices to come down.
|01-18-2008 09:16 AM|
|rhaley||The best route with LEDs (as has been mentioned here before) is to use colored LEDs for color applications. Not the cheap kind with a coating on the lens, but true red or green LEDs. They are more efficient, and the cost less than white LEDs. All that being said, if colored LEDs just aren't feasible for your need, the next best option is your proposal for white LEDs with a colored filter.|
|01-18-2008 06:38 AM|
My thought process was to replace white bulbs behind colored lenses with white LED's, so the "color flaking off" will not be an issue. I also bought a couple of red LED's to try in some of the cabin lights for night vision reasons.
As I said before, I have not installed them yet. Will have to wait till spring.
|01-17-2008 06:40 PM|
In most boats, I agree completely. It is just a trend in the industry to try and make the LED fixtures brighter and cheaper, and right now, the easiest way to do that is with the cooler white colors. More bang for the buck so to speak.
The LEDs that I have set aside for my own boat are much warmer (3000K), but will require an additional LED per fixture to get the desired light level.
I should also say that I am accustomed to using the various power LEDs from the big five manufacturers, and it seems that most of the fixtures and bulb replacements (for boats at least) still use the small encapsulated style of LED. The newer power LEDs offer a lot more options and I expect to see them more and more in the better fixtures in the future.
|01-17-2008 04:28 PM|
Originally Posted by rhaley View Post
The role I see for LEDs (aside from nav light replacement bulbs, which I hope are made compliant in the next couple of years), is as indirect area lighting in the saloon, as "floor lighting" on companionway steps (these could be red and quite dim), as engine room lighting, and as dimmable spots for chart reading at night.
|01-17-2008 10:49 AM|
Will we have to get hazardous waste permits to dispose of all the mercury in all those 'green' lights mandated by the us gov?
Will we have to pay unemployment ins to all the us labor that will get laid off when the chinese made 'green' lights are mandated?
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