Make ur own LED lights for bright but low consumption lights

[Iya]

Guys,

I am in the process of converting and adding custom led lights on my boat.
The goal is simple, I want minimal power consumption on this no-generator boat.
I don't buy ready made products, I use existing lights housing and solder m own leds on PCB cut to the
shape required to subtitue whatever bulbs.

The introduction of the new leds with color temperature close to pure white without the buish tint is what
making me wants to explore the posibilities. Been studying the leds for sometime now and I find that it has its place in
boats without generator.

However there are a few things one must understand about the characteristic of the leds.
It is actually voltage sensitive for ultimate brightness and life span. Can not stand much heat too.
The degree of the spread beam is also very important for different applications.
It is a fun project though.

To cut the story short, I am able to get roughtly of 40 watts of halogen equivalent brightness with 8 watts of power consumption and get nearly daylight color.

Designed properly, it is easy to save 75% of battery power consumption while getting the same brightness level.

On an overnight trip, assuming you need 12 hours of DC lighting, the led can do wonders. With as little as 5-7 amps per hour, I can brighten up the whole boat. Ironically to power up the instruments panel on my tripple engine alone is 2+ amps/hr down the drain and the anchor light itself is almost 1 amp/hr. Complete navigation lights takes about 3+ amps/hr too.

I have a friend who has an office in China and have guys flying in and out to Indonesia every 14 days, so I decided to buy from China, factory direct and with no minimum quantity ( rare ).
Checkout their website : http://www.hebeiltd.com.cn/?p=leds.5mm

For calculation of using resistor for the leds, here is a good guideline :
http://metku.net/index.html?sect=vie...dex_eng#series
I personaly use this calculator as a short cut but I fine tune my resistor needs using digital ampmeter to actually get accurate power consumption so that I can maintain 20mah per led or per array of leds. Play with the calculator and it will show how much is lost in heat ( watts ) when using a resistor.

Without the led lights I could not bighten up the entire boat for 12 hours without draining lots on the domestic bat bank.
I like boats very bright at night while anchoring.

I'll post some photos later when I get it organized.

Been a bit of headache to get optimal power consumption of the leds under different voltage input. White leds typically operate at 3.2V ( mine is ) and maximum at 3.6V ( but shortlived at this voltage ). I make 4 led in series to get the operating voltage at 12.7v. However if you study the datasheet, you will realize that keeping it stable at 3.2V and 20 milliamps is the best for longevity and low temperature operation. Most available units in the market uses resistor to limit voltage & current but that means it will not operate at 100% efficiency when boat at anchor, without something charging the battery to be at 13.8v to 14.2 volts. When battery is at 12.7 to 12.2 volts, those leds with built in resistor will typically yield about 70% brightness level and resistor itself consume powers ( small ) in the form of heat.
If one does not use resistor and set right at 12.7V with 20 milliamps consumption, the leds will be very shortlived at 13.8 to 14.2 volts because the current will jump to almost 40 miliamps and 30 milliamps is the maximum for a common led. Look at a LED datasheet and you will understand what I mean.

I tried making voltage regulator. I got the circuit drawings from internet. However, typical voltage loss of this VR is 1 volt and when by battery is not being charged, my 4 led in series is not getting 12.7v for optimum operation. I am not getting full benefits while overnight at anchor without a generator. If I set the led 3 in series and operate them at 9.6V, the VR itself will consume power (small ) in form of heat and I am adding a potential trouble zone in the system.

So after making 3 voltage regulators rated a 4 amps ( which is not easy to tune accurately to 9.6 volts ), I ended up not using them. Back to zero again.

I keep thingking that my priority is leds operation at anchor without a generator and maximum brightness for least power consumption and simple voltage regulation when engine alternator kicks in. Stupid as it may sound, I ended up using the resistor again but this time I place a 12V relay/contactor ( proven reliable ) in the system. When ignition of any 3 engines kicks in, the relay will close and make the leds get electric supply via a resistor to match the 14.2 volts I am getting with engine running. At the same time, I use a 220V relay/contactor to also operate that 12v relay if battery charger is operating while on shorepower. This way I get optimum brightness and life span from the leds while at anchor and while engine is running. Commercial available 12V leds light fixture in the market cannot function this way, unless high end models like some torchlights with built in voltage regulation.

The downside of my decision on such set up is the potential float voltage of the batteries immediately after engine shut down which is still at 13.8V+- for a while unless a load is applied. So in operation, my leds if turned with engine running and when I do kill the engine, the leds will be driven a bit high for about 5-10 seconds. The after effect I don't know yet, I am still simulating. Time will tell.

If one can design ultra low loss voltage regulator or loss og 0.3 volts or less while consuming minimal power, it should be a good add on for the leds if you want to put 4 white in series. The lower the operation voltage of the leds, the more power you will loose to heat. This is why I die to set 4 in series.

Right now I have converted the 3 typical cheapo 12V 50 watt halogen flood light with 64 leds or 16x4 leds array, consumes 12 watts for 60 watts equivalent brightness instead of 150 watts in original form. Looks cool with those ultra white light. Also have converted a dome 20watt halogen with 56 leds, consumes 3.6 watts for equivalent brightness of the 20 watts halogen. Replaced the typical Perko courtesy light bulb with 8 leds. At 8 leds I am consuming 0.5 watts compared to the typical 3 or so watts bulb for the courtesy lamp.

Later,
IYA

[ScottK]

WOW!

[tiara3100]

After reading your post and the headache your going through, it makes me glad to have a generator.

I have been working with LED's in various applications on my boat for the last 8 months and I have to admit, its a lot easier to set up the LED's knowing my voltage will be about the same at most times, either with power from the generator/charger or the engines running.

I could not agree with you more about the benifits of the LOW power consumption of the LED's. Even with a generator, my amperage draw at anchor on an overnite tuna trip was over 20amps with the 12v spreader lights.

Now, buy using LED's in various lights throughout the boat, I have reduced it to under 15amps. The only thing I have not replaced are the spreader lights. I have not found a set of white LED's bright enough to replace the halogan bulbs. I may have to try a few of the lights from the supplier you listed, but I am skeptical.

My current project is to build a floating light stick, similar to a HYDRA-GLOW from green LED's. The power consumption will be low and should be more reliable and less prone to breaking.

[knockdown]

Check out the AD8240

http://www.analog.com/UploadedFiles/...57AD8240_0.pdf

[CaptWill]

I wouldn't mess with the navigations lights. Will they still be USCG approved?

[Reel-Rascals]

CaptWill - 3/25/2006 8:11 AM
I wouldn't mess with the navigations lights. Will they still be USCG approved?

FWIW the red/green sidelight LED nav lights sold by Innovative Lighting are approved for 2 miles. See here. Capt Kevin (Megabyte) and I put them on our Parkers, see below, and they're an awesome upgrade!

[Iya]

Tiara,

If your spreader lights is the normal small rectangular and your cockpit is your Tiara 31 or you if installation is not on a tuna tower, 4 converted units like mine should do well. All in all you will get to use about 64 per light fixture, thus x 4 = 256 leds and only 16 watts or +-1.5 amps at 13.8 volts. For my converted 29 Luhrs, just two of the spreader/lights is bright enough for me to be able to do work ( diving preparation ) or even read a book. I don't know if led based spreader lights are available commercially for boat use, I know for residential or marina use they exist with like 200 leds array. My problem is making a custom housing, thus I am still using the existing housing available.

The simplicity of cutting the readily available PCB board with soldering holes for these leds is a big convenience and cheap too for custom work.
The cost of making 64 leds array per flood light is under US$17 ( light fixture not included though ). The leds are so light, I bought 560 pcs 5mm it fits in a normal medium sized business envelope for postal shipping.

If you enjoy custom work, make a 64 led array like mine using one with 40 degrees and one with 60 degrees leds, see which one fits ur needs. I bet you will be amazed with its brightness generated from a mere 320 milliamps draw. My rough estimate of 20 watts halogen equivalent is just my own guess not instruments measured. If I can read a book comfortably, it should be enough brightness there.

However overall brightness will depends also on your installation height. I bought 40degrees and 60 degrees white leds. 40 degrees is for the flood/spreader lights conversion and at installation height of 6.6 feet above cockpit floor, I get a typical beam pattern of about 2 x 4 feet very bright and about 20% extra spread of decent brightness. If i use 60 degrees led I will get better coverage but less intensity per square feet. My cockpit is about 6+ feet by 10 feet. The 60 degrees I use for interior lights or lights where my height to floor is less. For ur floating light stick, the 50-60 degrees green led will be the best choice.


Knockdown,
Thanks for the info. That is a very interesting product for possible future project.

CaptWill,
I don't inted to mess with navigation lights, there are ready made units USCG approved though and my anchor light bulb draw is small enough. If I need all nav lights to be operated, it means my engine is already running and I have alternator output to cover that. I am concerned only for floating around on pure battery power. I have isolated domestic bat bank, so I am safe for engine starting. This boat of mine will be located from time to time in rural area where shorepower does not exist. I will get a simple portable air cooled generator to charge the batteries but the more efficient the boat DC power consumption the better off for me.

THANKS GUYS..........

[jyasaki]

Your problem is typical for a lot of designers. You have gotten caught up in the "gotta be the [insert choice here: brightest, most efficient, longest lived, etc]" design goal.

You should have "Will it be usable?" as a design goal. It will save you a lot of headaches. Nobody cares if you get an extra 5 minutes out of your array after the 8 hour burn time. Nobody, that is, except you.

jky

[Iya]

Jyasaki,

Isn't the partial fun of boating is messing with the boat's stuff, to get more out of everything ?
To learn is to know more and have good fun in the process.
Lighting is very important for me and I will juice out maximum efficiency where and when I can.
The same as we try to juice out every bit of performance from our props combination, engine heights and so on.

"Will it be useable"....yep indeed the custom leds are very useable.
When the current draw is set right and corrosion protection on the array soldering and wiring is done well, I need not worry about these leds for about 10 years down the line. Initial time and effort well spent.

I don't know how is your user profile on your boat but on mine it will spend at least 6 months a year far away from parts convenience and operate always 125 to 250 miles away from home port. My country is not like the US where life savings agency is readily available. Here I am own your own 30 miles into the Indian Ocean where my anchor line will not reach the bottom. If I rigged my boat electrical, I set a 10 year trouble free instalation to the best I can.
While I am re-wiring the whole boat now, I might as well do my leds to lower my DC current draw and explore new leds offerings for a one time headache but long term peace of mind.

Later,
IYA

[jyasaki]

Didn't notice your location initially. I personally mess with stuff to the point where it works well, for me. At that point, it;'s time to use it. I'd rather be doing something other than working on the boat, namely on the boat, or off of it diving.

Didn't (and don't) mean to imply that you were doing anything wrong; just that I don't see how cutting the draw down by a few hundred milliamps is going to make a difference. If you feel it will make a difference, well, you're the one doing all the work.

Have you considered a zener diode in parallel with the LEDs to hold your operating voltage constant? Should help to stabilize some of the voltage induced variance.

BTW, pretty good link you had for the LED source point; forgot to thank you for that earlier.

jky

[Iya]

Hi J,

Great !!!! Same hobby we have, I am a keen diver but I spearfish not sight seeing and I blow bubbles. I assume you are a freediver based on ur CA location if you spearfish too. I sometime freedive too but only in certain location. A friend also adviced me on the zener diode, he is an electrical engineer and I am not, just a hobbist. I might try that, many thanks for the same reccomendations.

I am not cutting just a few milliamps draw. In current state without leds modification, I am looking at 156 watts constant use at night for diving and at least 56 watts while without activities or while sleeping the night away. With the leds, I get to use only under 30 watts to keep the entire boat bright at night. That's the whole purpose. The near daylight color of the leds also makes me feel better than the amber glow of halogen. You know how it is with regular bulbs and halogen, bad contact occurs very fast especially hot halogens receptacle or connections. The led if immersed in epoxy can be a very tough ultra waterproof units.

You are welcome for the leds source, I think their price is very competetive for a factory type of sales without minimum quantity. I also like that they provide the datasheet which is the most important part of the whole project. No need to guess the parameters.

Dive Safe J,
IYA

[jyasaki]

Iya;

Thanks for the biography. I, personally, am not much of a freediver; I go for abalone, but that's about it. I mostly shoot pictures on scuba. I also shoot halibut (when I can find them) or a few rockfish for dinner. Not really much of a hunter.

On the power saving thing, I was talking about your current LED design vs. fine-tuning your current LED design. I am completely aware of the savings you'll get going to LED vs incandescents.

Best of luck;

jky

[TG_190]

Rather than a Voltage regulator, A tuned DC-DC converter will do it. Trouble is they are more expensive, and are optimally efficient at a certain current (i.e. they have to be sized right). The good news is that with a single DC-DC converter, you could put all of the 3 LED clusters on one circuit (with individual switches). The DC-DC converters I am familiar with are from 70-95% efficient: So, if you mostly use all of the LEDs at once, you can size it to be over 90% efficient. If you want to only use one, the efficiency will drop down, but so will the overall current draw.

You must be an EE.

[Iya]

J,
Yum......... yum the abalone. I am more of a video guy ( when I borrow a video cam ). UW photo seems tough unless visibility is good.


TG 190,

Thanks for the input on the converter.
I am not and EE, just understood some AC & DC current basic but not much on semiconductors.
The user profile of the leds is very variable, anything from 200 milliamps to about 3-4 amps. I have seen a 10 amps 24 to 12 VDC converter for VHF on bigger yachts and they use like 0.5 amps while on stand by. This is the same reason I don't want to use the voltage regulator. The 4 amps voltage reg I git from the internet is not that stable when variable load is applied. Therefore now I have to trouble myself to use resistors per separate zone, hoping failure will be limited to each zone.

Its quite lucky that I get a led with 3.2 forward voltage for optimum 20 milliamps. If I get a unit with 3.6 volts, I can't get optimum 20 milliamps at 12.7V battery own voltage without charger when led in series of 4.

Let me do some burn endurance test and see what happens. Thanks again.

IYA