Globe/bulb lightning up in seawater

Interesting article here about LED running lights.
It talks about efficiency of using RED and GREEN LEDs, so you don't need colour filters.
http://www.duckworksmagazine.com/09/howto/led-nav/index.htm

 

Using red and green LEDs for running lights is a wrong choice. Their intensity over a 120 degrees viewing angle is very poor compared to a white LED that is actually an UV one exiting a white Phosphor. The white LED has a large flat surface that emits light in all directions whereas the colored ones produce a narrow beam that needs a reflective cavity to distribute the radiation.

Theoretically it is possible to make colored LEDs with multiple elements on a single chip, but it is commercially more viable to use a white one with a colored filter.

 

I agree. I need to find out more about the automotive LED's placed on a heat sink already. Some of them transmit extremely high intensity out. Good enough for 3nm. I have here some green 15 Candela (15.000 milliCandela , typical Marketing people) , white 18 Candela and Red 13 Candela. But they are like CDK said, very narrow beams.

Jemie, thank you for the information. I will go over it and see whether we can get some sensible tests done for distance. Do they mean with a binocular or with normal eye sight etc. I unfortunately have fallen ill and have to take it easy for a couple of days. Bert

 

LED's

The one's I am looking at are the one's from OSRAM. I have over the last 40 years used their products with great success.

http://www.osram-os.com/osram_os/en...ng/index.jsp?gclid=CNvQ8Nmp2sYCFWLKtAod85AMSQ

Bert

 

Take care Bert and get well soon.

 

Thank you Jamie, What antibiotics can do is a blessing, although I have to take it easy. To come back on this project. I made for my home, using 12 x 12 Volt LED lights, which switches on, when the electricity fails, but if there is daylight, it does not switch on. The battery, a 9Ah sealed led acid batteries get recharged as soon the electricity is back.

That was simple.

For the boat, I have to try to get the smallest and best components available for this project and that may not be easy in this part of the world. I am also wondering whether this is a good project for KickStarter, this in view that I may not be able to offer anything after the first round and have to find somebody else to carry on from there. Thus I first have to make one with small discrete components and with a small micro chip for my own boat . My friend who worked for OSRAM, who has also retired like me from another large German company, is no longer able to help me with small quantities, although they have the right components, the 1 watt and the 2 watt LED on a heatsink.
To enable me to get 3 Nautical Mile, I have to try to get hold of those one. I may then be able to put something together for myself. Bert

 

I have emailed OSRAM, in the hope that I am getting a positive response. Bert

 

A reply from OSRAM was received a few minutes ago.

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In your case I would recommend you look at the Oslon range as they offer high robustness against corrosion and the power output you required.
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Have a look at:
Oslon Square - http://www.osram-os.com/osram_os/en...s-for-general-lighting/oslon-square/index.jsp
Oslon SSL 80 (80 degree radiation): http://www.osram-os.com/osram_os/en...general-lighting/oslon-ssl-80-white/index.jsp
Oslon SSL 150 (150 degree radiation): http://www.osram-os.com/osram_os/en...eneral-lighting/oslon-ssl-150-white/index.jsp
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You did not mention if you require any other color than white, but we do get the SSL range in color as well.

I’ve also copied Cloudio Brown from EBV. They are our local distributor and can assist with pricing and samples.

Mit freundlichem Gruß / Kind regards

 

Jamie, it seems you are the only one who took an interest in this project, apart of CDK and readers living in Belgium, who can solve their problem when the mains falls away.

Therefore I had another look at a practical solution of the problem and I probably would do it slightly different. I just place a 5 Amphour or 9 Amphour, 12 Volt Sealed Lead acid battery, with 2 Shottky diodes in line before the 3 most important switches, like mast, stern and starboard light. The battery will be kept full, minus 0,3 Volt and as soon the battery/generator/alternator falls away, at least those important lights stay on for a few hours. By waterproofing the diodes and the connections, it could be an equal and more economic solution.

Attached the circuit diagram.

As soon the OSRAM samples I ordered are coming in, I will have a look, whether it is not going to be too bulky with the appropriate lithium battery.
As soon it is too bulky, the project is dead.
Bert

 

Something sailors should be aware off. Most high power LED lights like stern lights, mast lights etc, has a constant current circuit build in. One should be aware of the following problem. The law of Ohm is, lower voltage , lower current because the resistance stays the same. This is not the case with lights containing a constant current circuit, as it keeps the power constant over the LED itself. It means that your battery voltage drops, the current goes up. If you have many lights on and in parallel, the battery suddenly get drained very fast, this apply to your main battery or also to the above circuit with a buffer battery.
Bert

 

Unfortunately, it seems that the agent for OSRAM has let me down, no samples has come in and I took some LED lights with Cree high power led’s to pieces. I have a small order from a customer to develop the idea further. The idea may be noble to place a lithium battery in a mast, stern and other important lights, but space is very limited and the proposal in thread no 24, is a better solution. However I would make a simple circuit, which senses the battery voltage and let the relay drop out when the battery voltage drops below 11.5 Volt. (0.5 Volt transistor basis voltage + 5.1 Volt zener-diode (C5V1) + 5.6 Volt second zener-diode (C5V6) ) or one zener-diode of 11 Volt, if one can get them easily and a transistor + 12 Volt high resistance relay with a 10 Ampere contact. The reason is decribed in thread no 25. Bert