Need help here !

[29cascadefixer]

I have been slogging through this fixation for the LED Anchor light. I thought that using an incandesent light that had Coast Guard approval as a bench mark would give me a brightness standard. Unfortunately, they use two different standards of measurement. Incandesent uses Candlepower, and LEDsuse Microcandela. So, with more research, I found that I could change them both to Lumens,it would work. I found two veryhelpfull sites on this.

Okay- two sites here
http://www.theledlight.com/lumens.html
and here
http://www.dcwi.com/~nybarra/LED.html
Ok,the light I found was sold by Sailnet for about 12 bucks. It uses a 12 Candlepower festoon bulb. So this is where I want my math checked .
Lumens = 12.57 times 12 candlepower=150 Lumens..right ?
and
Lumens=2 pi(1 - Cos 1/2 beam angle) times Microcandela, so the LED I checked it out withhas specs of 2500mcd ( Microcandela) at 45 degrees of beam angle.---so
Lumens=6.28 times( 1minus Cos 22 degrees) times 2500 mcd
so Lumens = 6.28times( 1 - .927) times 2500
Lumens =6.28 times( .073 )times 2500
Lumens = .458 times 2500
Lumens = 1146 lumens
Right ?
Looks like these LEDs will do the job, Right ?????

[29cascadefixer]

Shucks. I post something intelligent and everyone dissappears ! I'ma going back to chewin' tobacco and spitten by Cracky. All these smart folks on here ( sniff) won't give me an answer ( snifffff). Dumb 'ol me (sniffle), kicked to the cyber curb, ostrasized ! Try to improve yourself, ask something uplifting and get IGNORED ( SNIFFFFFFFFFFFFFFF)! Gonna go someplace and POUT , daggummint. Woe-woe-woe ! BAWWWWWWWWWWWWWWWWWWWWWWWWWWW

[sy Dolce Vita]

not ignoring you . just digesting

[GordMay]

I'm not familiar with the formula (nor it's application), but the 1146 lumen figure seems (intuitively) high to me.

For comparison:

Incandescent Lamp Output Efficacy < 20 Lumens per Watt
60 Watt Par 38 is 880 Lumens
60W 'a19' is 890 Lumens
75 Watt Par 38 is 1050 Lumens

Compact Fluorescent Lamp Output Efficacy > 40 Lumens/Watt
9 Watt 'PL-S 9W' is 510 Design Lumens (600 initial)
18 Watt 'PL-C 18W ' is 1050 Design Lumens (1250 Initial)

How many LED's are assembled in this $12 Festoon?

Regards,
Gord

[29cascadefixer]

I think I found out where I made a mistake due to enthusiasm. I multiplied BY MICRO-candelas instead of converting to Candelas. So the final multiplier should have been 2.5 instead of 2500.
Lumens for the LED chosen= .458 times 2.5 = 1.145
1 1/2 Lumens per LED .Hmmm looks like I'd need a hunnert of them suckers to match the output of the Incandescent. Have to keep looking I guess. Still think I can do this.
Thanks for the input Guys.

[greenrayled]

It is not hard to make a LED anchor light...but is is more difficult to make one that will be bright at all required voltages, yet will not burn out at higher normal voltages, and is also able to take advantage of leds inherent efficiency and not waste power. I have a lot of info on DIY led lights if anybody is interested. I can send it as an attachment (text and some graphics) if you send me an email address.-Ken

[Alan Wheeler]

You have to remember that part of this forum is World wide. And some of that world is either asleep, at work or what ever, when you may be at your PC surfing and expecting an answer
But anyway's, LED has only one advantage over any other light source. Eh, man made light source that is. LED will last longer and is more robust than filiment bulbs. And that is where it ends. They are just too low in their light output to be of much use. Unless you have a lot of them. But then, it actually works out that they consume more power than a standard type bulb. A fluorescent type light is still the most effiecient power/lumen ratio available.
Then of course, you have to have a voltage regulator in the LED circuit somewhere.
As for Lumens, not all them little criters are measured the same. You need to read the fine print and find out how the little sucker was measured.

[jim lee]

I've been bitten by this LED idea as well. I'd like to have a tri-color with the anchor lite on top. Maybe 3/4" diamiter 4" long tube? One neat thing about the LED stuff is the finished product can be potted in a solid block of plastic.

Wheels you sure them super bright LED's don't put out enough. They just about sizzle your retinas lookin' at 'em.

Here's one I was lookin' at : Jameco White LED

That one has 3,700 mcd.. So, what's a mcd?

-jim lee

[Talbot]

There is no problem with achieving a light bright enough using LEDs, however, you need to check a couple of things, the first and most important is the beam angle, cause this is where the LED suffers by comparison to normal bulbs. You need to create a bulb that shines throughout the angular distance of your light (both horizontally and vertically), and also pushes out enough power to meet the light requirements. For Nav Lights, you then have another problem, cause the light fitting is certified only with the correct bulb fittted! AFAIK there are only a couple of manufacturers who have nav lights and anchor lights authorised by USCG, these are PERKO, and Hella. Aquasignal are developing one, and Orca Green are in the process of obtaining approval att the moment. They also make an insert for other lights. These inserts use abt 25% of the power of a normal 25w bulb.
There is another manufacturer who makes the most efficient replacement bulbs (but also the most expensive) - DeepCreek

IMHO it is only worth replacing the tricolour and the anchor light, cause you will be using the engine when you have the others on anyway.

[Wahoo Sails]

Yo guys,
Not to change the subject ... but ... a Respected magazine tested all of the available nav lights on a very practical basis. They are required to be visible at a distance of 2 miles ... so they set them all up, and went 2 miles away ... the onlylight visible was the one produced by Hella!!!! If ya wanna make comparisons, might I suggest you use the Hella as your benchmark! Along the same lines, I have a masthead mounted tri-color (of unknown manufacture) am planning to add an Aqua Signal bi-color (on a seperate switch) to the bow pulpit (uses the same BIG bulb as the Hella) .. it's supposedly against regs to run 2 sets of nav lights on the same vessel ... anybody else using 2 sets of nav lights? thoughts?

L S/V Eva Luna

Bob

[Jeff H]

My boat has two sets of running lights, a masthead tricolor and a set of deck level stern light and combination bow light. I use the tricolor when passage making or out in open water (even open water as small as the Chesapeake Bay) since I believe that the tricolor is visible from further away and clearly uses a lot less amps. I use the deck level lights when in more confined channels or when motoring. I never use both at the same time.

Jeff

[Euro Cruiser]

...but it isn't cheap.

Beam width can be addressed by selecting the proper LED. E.g. for those of you with propane stoves and a galley-mounted propane solenoid switch, you'll notice your LED can be viewed from a wide range of angles - just as the mfgr. intended. If that LED fails and you plan to solder one in its place (I just had to do this...) be sure to select the correct beam width (I didn't...).

An LED-based anchor light (and/or Tri-color light, as Jeff is describing) will need two things to work: a multiple LED array (many LEDs, clustered in a circle or 'wafer') to form the necessary 360 degree arc, and multiple 'wafers' in order to get adequate brightness.

At the SSCA Gam last week, I looked at a new product being offered by a firm down in Marathon that is a direct swap-out for the Aqua-Signal fixtures. For the combo anchor/tri fixture on my boat, I could buy an LED-based insert that would allow me to keep my existing dual fixture, provide me with 2 or 3 wafers for either of the lights, plus all the control electronics, and the amp loading was 80 milliamps - roughly 1/15th the current draw of my existing set-up. The lights appeared very bright and, given the arcs of LEDs, did not appear to suffer from dead spots, either vertically or horizontally.

The catch is that the retrofitting requires about $180 USD.

Jack

[John Drake]

LED light technology has gotten much more advanced and there are now some very bright LEDs that can be used for external nav lights. Using them in the cabin has other issues. The color balance of white LEDs down below tends to be quite cool and thus gives you the feeling of being in a morgue on a dark and stormy night with half the lights burned out. I DO use the Davis 15mm LED replacement light in my reading light. It works very well and it bright enough. Saves A LOT of power (as I read a lot) and is pleasing when used in the glow of a couple oil lamps.

My Orca Green Marine LED navs lights are very bright and I am certain they can be seen at the required distance. I looked into LED anchor lights and found most are expensive (overpriced really). OGM does make the least expensive one (about $100) and the company states that it IS USCG approved.

I found using the Davis Mega light as my anchor light works well and has just a bit more draw (320mA?) than an LED anchor light (about 250mA for some). It is cheap, reliable and approved. I also like to use this light mounted just above the coachroof as that is more in the line of sight of someone piloting a boat through an anchorage (how often are they look UP?).

Just my 0.02. I think LED technology is great. It is far easier to conserve power than it is to make it and store it.

My best to all

John
s/v Invictus
Hood 38

[RPC]

As an interesting coincidence, BBC Radio 4 had a program today about this very subject!

It said: Within 15 years, the light bulb, will fade into history. Scientists say the light bulb is being superseded by LEDs - light emitting diodes. We speak to Robert Wheeler, the great, great grand-nephew of Thomas Edison, the inventor of the light bulb.

If you want to listen to the whole thing on the web this is the link:

http://www.bbc.co.uk/radio4/today/li...20031208.shtml

The program time was 0745

It may not help you solve the problem now, but if you want to wait a few more years? .....

woops, the date of this link says 2003, but I heard it on the radio today, so you may have to search the site a bit, maybe its a repeat?

[29cascadefixer]

When I started this subject, I was interested in trying to duplicate the performance of a regular anchor light with LEDs to conserve Amps and to save replacing a Light bulb at the top of a mast to often. And to do this cheaply by doing it yourself. I studied the Beam Angles. I studied the circuitry as best I could. I bought the components ( most of them ) on E-bay. Unfortunately when I finally did get the components together, Spring hit and Ol' Cascade Fixer started re-fixing a Cascade 29.
Sooooooooooo, looks as though it's time to start assembling the components and see if a fumble fingered ol' mechanic can make something out of this hodge-podge of parts.
Heres where I stand . I have 20 tight beam LEDS . I have a voltage regulator to kick the load package ( LED Lamp) down so it will work at 9 volts so if a battery voltage drops to almost totally dead, the lamp will still work. I have photo electric transistors that will kill the lamp at dawn. I will see this Winter if I can get this to work. By the way, if I can get this to work, I'm thinking of a further refinement. A power diode working from the Alternator Voltage so that when motoring at night the lamp automatically goes off.
If any of ya'll wanna come up with something to do all this, please feel free to tell me a different way. I hate thinking at my age.