# Green LEDs



## jc32754 (May 22, 2011)

I am a novice when it comes to LED use. I want to construct an underwater light to use for shrimping here in FL.

Someone currently is making them but I want to try to improve on his design. I want to produce a 360 degree light with the most possible lumens. The current light uses a flex strip of RGB LCDs. It uses only the green and looking on the Internet I think I found the one they use and it is a 1200 mcd @ $30 each and they use 2 strips.
http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&Page2Disp=%2Fspecs%2FRLBN-RGB30SMD.htm#photos

My idea is to use some brighter and am looking for advice.
Jim


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## Lampyris noctiluca (May 22, 2011)

Hi Jim,

If you use leds such as the Luxeon Rebel or Cree xpe, the shrimp will need welding goggles, as these leds are so much brighter than the superbright 5mm leds!!!!


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## black_ice_pc (May 22, 2011)

If you want max output, you definitely don't want to bother with that strip. Get something like an XP-E as stated above ^. Each one of those will kill a light strip, plus they're alot more compact.
Along with the LEDs you'll need a driver and a power supply, and a housing to keep them dry of course.


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## jc32754 (May 26, 2011)

Thanks for the replies. 
Excuse my ignorance but "driver"?? I looked up some info and think I found the driver is a voltage/current resistor, yes? How do I determine what size R I need for either of these two suggestions? 

As for power supply, I will use a waterproof system connected from the sealed bulb enclosure to a 12 V storage battery dedicated to this light.

The idea is to 'corral' the shrimp into a 'kill' zone using the lights to 'funnel' them toward the boat in a tighter path, so the need for welding goggles is good!! 

If the battery is connected with the polarity reversed, does it cause damage? or do they just not light up?? IF damage, how do you prevent damage from a reverse connection mishap??


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## black_ice_pc (May 27, 2011)

No problem. There's no dumb questions. LEDs need a current controlling driver. It's basically a transformer that converts the power coming in, say 8.4v from two batteries, to the proper voltage for the LED. It also regulates the current(amperage) going to the LED. Without a driver or at least a resistor, the LED would likely go . 

I'm sure someone else may be able to further assist you in choosing an appropriate driver, but I have personal experience with the BuckPuck drivers. I use them for DIY aquarium lighting. They're plenty small for your application. They sell them here. Something like that would drive a few green LEDs well, and it's dimmable too. To make up a DIY light, you'll need general electronics knowledge and some soldering skills. Basically the electronics go like battery>driver>LEDs. 

If you were to use some XP-E greens driven at 1A, you'd definitely have a crazy amount of light. I.e a 6 LED array could easily light a living room, albeit in an eery green 

Edit: forgot to address the reversing polarity. Doing that with LEDs is a definite no-no. It can kill the driver.


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## mahoney (May 27, 2011)

just something else to think about...how you are going to get the waste heat out? The surrounding ocean will make cooling easy, but wanting light coming out of your enclosure 360 degrees will make it somewhat of a challenge to have the heatsink in contact with the water. Perhaps 3 or 4 lights rigged in a cluster, each light having a lens on one side and heatsink on the other. 

There are lots of drivers out there, Xitaniums are big and expensive, but fairly easy to figure out which one you need and how to wire. Places like Dealextreme or Kiadomain have lots of choices, cheap, but it may take a long time to receive your order, or ..., caveat emptor


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## hellokitty[hk] (May 27, 2011)

There's the SST-90 color, green version obviously.


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## Toaster79 (May 28, 2011)

You could go for 6 green XP-Es on 10mm round MCPCBs with Ledil Tina2 10mm optics and lflex. Wire the LEDs in 3P2S configuration, set the lflex to 3A drive current and supply it with 2SxP LiIon battery pack. Take 50mm ali hex rod and machine the openings for LEDs and optics in each of the six sides. Make a 21mm ID pocket in the center of the rod to squeeze in the lflex and seal it.

Voila:


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## jc32754 (May 28, 2011)

Your suggestions sound really interesting. I don't understand a few things.

What is Ledil Tina2 10mm optics?
and Iflex? Is this a driver?

I presume "Wired 3P2S" means wire in three in parallel two in series so that the maximun current demand does not exceed the power source.

What is a 50mm ali hex rod? Is that a 50mm aluminum hexagonal rod that is readily available in metal shops?

Why would I need a 2SxP liIon battery pack? The deep charge trolling motor batteries 12V won't work? These units will be used from boats so carrying a large lead acid battery is not an issue. (Besides, I need the exercise)

Is a heat sink absolutely necessary? I understand heat is evil when it comes to LED lighting but the heat is an issue, how does it effect the life and brightness? If the LED is rated for 50,000 hours and heat reduces it to 20% or 10,000 hours, should I worry about it? I don't think I will be using these for anywhere close to 10K hours.

Black Ice, you say that a polarity switch will kill the driver but if I am using just a resistor, what will happen?

Toaster, I am not sure how your mounting system works. I think you said to use the hex rod to mount the 6 XP-Es. If you do this, presume you use screws to mount them. This then would create a heat sink. Yes? Now if I am going to use the source as a 12V 'car' battery, no Iflex needed?

As for wiring, each XP-E would be wired 2P3S with the wires fed inside the hex rod, connected to the power supply cord?

Would a dab of epoxy be better to mount the LED to the hex rather than screws?

I did some additional checking and the strip that I think was used on the other light maybe the NFLS-60G http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&category=BARS&Page2Disp=%2Fspecs%2FNFLS.htm which makes 72,000 mcd for the entire strip
drawing 200mA. Just to clarify, are the 6 XP-Es capable of producing more?
Thanks.....


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## hellokitty[hk] (May 28, 2011)

> Is a heat sink absolutely necessary? I understand heat is evil when it comes to LED lighting but the heat is an issue, how does it effect the life and brightness? If the LED is rated for 50,000 hours and heat reduces it to 20% or 10,000 hours, should I worry about it? I don't think I will be using these for anywhere close to 10K hours.


No, they will fry and die on the spot.


> Would a dab of epoxy be better to mount the LED to the hex rather than screws?


Screwed in, with thermal paste in between is better than any thermal epoxy.


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## VegasF6 (May 29, 2011)

jc32754 said:


> Your suggestions sound really interesting. I don't understand a few things.
> 
> and Iflex? Is this a driver?
> QUOTE]
> ...


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## VegasF6 (May 29, 2011)

Oh got it, you are saying LFlex. Haven't heard of that one. D2Flex yes.
http://www.taskled.com/lflex.html

(way to go George a new product  )


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## jc32754 (May 31, 2011)

Thanks for all the replies. I have been looking around to find a KISS answer to my project. The need to make it 'plug and play' is pretty important at this point. My main objective is to produce a unit that will outperform the 72K mcd of the existing unit. While browsing I found the following:http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&Page2Disp=%2Fspecs%2F24-xHP.htmThis looks like a KISS answer if I put 8 of these in the unit my output would be roughly 3X the current unit. These look like I would not need a driver with them. I wasn't able to match a base to these but at a cost of $2.49 each X 8 = $20. plus the bases at what $1.25 each?? So my electronics would run me $30 plus the housing to keep them all nice and dry. Comments please. And THANKS for the help.


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## Suncat33770 (Jul 14, 2013)

Hi,
I know this is an old post but I am hoping you have that easy plug and play solution??? I want to try shriming in the Tampa Bay Area.











jc32754 said:


> Thanks for all the replies. I have been looking around to find a KISS answer to my project. The need to make it 'plug and play' is pretty important at this point. My main objective is to produce a unit that will outperform the 72K mcd of the existing unit. While browsing I found the following:http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&Page2Disp=/specs/24-xHP.htmThis looks like a KISS answer if I put 8 of these in the unit my output would be roughly 3X the current unit. These look like I would not need a driver with them. I wasn't able to match a base to these but at a cost of $2.49 each X 8 = $20. plus the bases at what $1.25 each?? So my electronics would run me $30 plus the housing to keep them all nice and dry. Comments please. And THANKS for the help.


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## AZReptile1 (Sep 7, 2014)

Anyone have any updated solutions/reports to this project?


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## The Led Machine (Sep 17, 2014)

I know its an old thread, but I think its really important to note that you MUST use GOogles if you are about to work with Luxeon Rebel...

A friend of mine was trying something similar and he ended up in the hospital... was not deadly serious, but still.


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## Epsilon (Sep 17, 2014)

Sorry man, but that goes for all intense light sources, common sense goes a long way. LEDS are not dangerous in the extend that lasers are, they do not produce that kind of spot intensity without lenses.
I am not saying that goggles aren't recommended, but saying they are a must is exaggerated. Exceptions are the exotics like IR (although the same thing applies as visible light) but especially UV. 

Warnings are fine, but sometime I wish they were not given for obvious things (US is king at giving obvious things as warnings, like do not put living things in the microwave....), the problem would solve itself .


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