900 lumens regulated LED rock or roof lights

[glenyoshida]

I admit I have an unusual love for bright LEDs so this may not do for you what it does for me but check this out.

The short story:
- These LED lamps shine 900 lumens each
- LEDs = half the power demand
- LEDs are more robust
- You save overall because you don't have to do as much change to your vehicles charging system to meet the new power demands.

OK, for you normal people, why is this so cool to a guy like me?

LEDs are vastly more efficient and are far more robust. A regular 50 watt halogen bulb will create about 580 lumens of light but it takes 4.2 amps to do so. Most of the energy put into the halogen is lost in the form of heat. These LEDs are so much more efficient that they will provide 1350 Lumens with the same amount of energy. So can run your lights twice as long before depleting your batteries to the same level. In my case if I end up adding a dozen LED lights and run them all at the same time (5 in the front, two on each side, and three in the rear) then it would mean I'm demanding an additional 33.6 amps. To get the same amount of light from Halogens I would need a whopping 78 more amps available from a new alternator, regulator, and wiring. Price for a 140 amp alternator with exchange: $185.00 (http://www.maniacelectricmotors.com/hiou140amp194.html) If I run say 3 - 5 LED lamps at once or all 12 for a short duration I probably won't even have to change out my stock alternator.

One of the biggest strains on a light bulb is turning it on and off. The uneven temperature in the filament causes a lot of stress in the filament metal and eventually causes the filament to break. That's why if you've noticed light bulbs often burn out at the instant when you turn on the light. Vibration on the trails also is hard on the filaments. LEDs are solid state and don't have a filament. You can cycle them on and off thousands of times and it will be a fraction of the wear compared to a regular bulb. You will probably never have to change out an LED lightbulb unless you physically damage it with a rock or something. That's another cost savings. If however, you are like me, a moth to a flame, and want to get the brightest thing out there you will likely loose money because it won't be long before a new brighter LED is released. :(

These lights still need to be mounted on an additional heat sink such as aluminum but the light has a built in regulator that works from 3.6v - 8.4v so you can wire two or three in series, run them direct, and get the voltage they want without having to buy and LED driver.

Link to buy the LED for $34.90 shipped: LED Light (http://www.dealextreme.com/details.dx/sku.14413)
Link to Buy the glass lens for $1.31 shipped: The Lens Cover (http://www.dealextreme.com/details.dx/sku.5948)

SSC P7-C 2800mA Regulated LED Module with Copper Base (3.6V~8.4V)
http://www.dealextreme.com/productimages/sku_14413_1.jpg


Wide spill pattern
http://www1.dealextreme.com/productimages/sku_14413_6.jpg


Glass lens to seal out dirt and debris (52 mm is = 2 inches)
http://www1.dealextreme.com/productimages/sku_5948_2.jpg

Like always I sure would like the time to mod this up today!

[Seanz0rz]

HAHA! thank you for doing some of the foot work for me.

im about to add LED's to the truck instead of standard incandescent bulbs, both as rock lights and rack lights. i was actually looking for something with a bit more throw, esp for rack lights, but these might be great options for rock lights.

thanks for the post!

[glenyoshida]

If you find a narrower reflector/lens will you please post up here? I found this PDF of various beam spreads (http://www.sekonix.com/modules/catalogue/(P7)_P7-CL_spec.pdf) so I know they are available but wasn't able to find out where to get them.

[Small_words]

Incidentally, LED's are a derivative of lasers. This is what gives them their intensity and low power requirements.

[mastacox]

Incidentally, LED's are a derivative of lasers. This is what gives them their intensity and low power requirements.


That's incorrect, they are two completely different technolgies and their intensities and power requirements have nothing to do with each other.

[4x4mike]

I admit I have an unusual love for bright LEDs so this may not do for you what it does for me but check this out.



You'd be surprised. I have 10 Cree XR-E LED's on my 4runner (4 as rock lights, 2 in each dome light and 2 in my hatch light). I like the small stars because they can be mounted anywhere and are easy to heat sink. My rock lights are in modified 1" copper caps and expoxied in. The dome lights are fit into the stock toyota dome light housings. 2 are run at 500ma and the rest are at 700ma, which amounts to a ton of light with little draw.

I have heard good and bad from Deal Extreme stuff. People have had all kinds of different experiences there, check candle power forums. All of my led's have come from cutter in AU. Prices and quality are the best that I've found on the interent and the good thing is that you can buy regualators from them as well. For my taste the P7's are too big and a little much for rock lights. Maybe for some back up lights or if you have a rack. I've been eyeing the P7 Mag from elektrolumens for some time now. The only thing that has kept me from buying it is that I already have a 1000+ lumen mag the same size. I think the P7's are pretty cool but I know nothing about regualting them.

Under electrical:
http://www.ultimateyota.com/index.php?option=com_smf&Itemid=26&topic=4960.0

[4x4mike]

Glass lens to seal out dirt and debris (52 mm is = 2 inches)
http://www1.dealextreme.com/productimages/sku_5948_2.jpg



One of my concerns would be sealing this up. The cree's have a dome that encloses the LED. All of my electrical contacts and regulator are sealed so they're waterproof (been tested with some stream crossings and a winter). If it were me I'd buy the P7 emitter and install them into already available housings. Ones that already have a mount and are sealed.

[4x4mike]

Here you go:
http://elektrolumens.com/Mag-P7/Mag-P7.html

Something to spend some money on. I was told that the 3D size with good rechargeables will last 4 hours. The 2D size with 3C's in it will last 2 hours. That's a little better than my Borealis which is about 1:20 runtime. It's incan though so the tint is nice for throw. Unless you can chose the tint with an LED you might end up with a blu-ish (or less than white/yellow) color which makes it difficult to see some objects at a distance, say ~200'+.

[Small_words]

That's incorrect, they are two completely different technolgies and their intensities and power requirements have nothing to do with each other.
[/quote]

How do you say that? Lasers generate light due to energy being released in the form of photons as electrons return to a lower energy state. In the correct environment, this emitted photon then 'feeds' another electron, forming something of a cascade. This forms light amplification by stimulated emission of radiation, Laser. LEDs operate on the same principle, though do not lead to stimulated emission, therefore not lasers.
http://www.rp-photonics.com/light_emitting_diodes.html
Did I miss something?

[Robinhood4x4]

Glen, have you used the P7 yet?

Looks like one can get the emitter and heatsink for about $20. Being one who likes to build things from scratch, does anybody have any instructions on building a driver that can handle that much power?

[paddlenbike]

I have built drivers based on three different linear circuits and they can range from semi-efficient to totally inadequate. If you can drive a LED (or series of LEDs) without relying on your integrated circuit to drop a bunch of voltage/amperage, a cheap linear circuit will work just fine. In other words, if you run three 3.3V LEDs in series (9.9V total) from 12 volts, you are only dropping 2 volts at the regulator. However, try running one 3.6V LED from a 14.5V car battery running at 2.2 amps and you are now dropping 10.9 volts x 2.2 amps or 24 watts. That is a totally unreasonable amount of heat to ask a small LED circuit to dissipate. So, my experience tells me to match total LED voltage to your source voltage and run them at lower amperages if you want to use a home-brew circuit. Otherwise, you're stuck with buying a more expensive DC-DC switching regulator.

[glenyoshida]

Glen, have you used the P7 yet?

Looks like one can get the emitter and heatsink for about $20. Being one who likes to build things from scratch, does anybody have any instructions on building a driver that can handle that much power?

No, I have not used them yet other than a unit in my flashlight. It's not real high on my priority list but it sure will be a fun project later. I think I'd like to get my gas tank skid done as well as some other armor first.

[glenyoshida]

I have built drivers based on three different linear circuits and they can range from semi-efficient to totally inadequate. If you can drive a LED (or series of LEDs) without relying on your integrated circuit to drop a bunch of voltage/amperage, a cheap linear circuit will work just fine. In other words, if you run three 3.3V LEDs in series (9.9V total) from 12 volts, you are only dropping 2 volts at the regulator. However, try running one 3.6V LED from a 14.5V car battery running at 2.2 amps and you are now dropping 10.9 volts x 2.2 amps or 24 watts. That is a totally unreasonable amount of heat to ask a small LED circuit to dissipate. So, my experience tells me to match total LED voltage to your source voltage and run them at lower amperages if you want to use a home-brew circuit. Otherwise, you're stuck with buying a more expensive DC-DC switching regulator.

Great info man! Thanks for posting up. Makes a lot of sense.

[glenyoshida]

I talked to a local shop that specializes in rebuilding alternators for trucks and plows and such. Knowing little about alternators other than the basics I was surprised to learn that upgrading the stator to a high amperage output might be at the cost of low RPM alternator output. The tech there was saying that I might get less output at Idle than my stock 80amp. Just like every project there's always something to make things more interesting.