Are offroad LED driving lights really that hard to build?

[Changchung]

This one must be brighter:

ebay 220873170077 Use a XM-L

this models in DX look promising use 4 cree xpe

SKU 72209

SKU 72210

But maybe all those get very hot. And you must to connect two diodes in serie to down the voltage a little to 12v



By the way, I do this some months ago;

Maybe you can use several of them.

 

[guy48065]

How did those LED bulbs work out for you in such small steel housings?

 

[Changchung]

How did those LED bulbs work out for you in such small steel housings?

The work great, I use it all the time, most in day time. This model dosent heat it to much...


SFMI4UT

 

[och]

The LED MR16 replacements have a long way to go before they produce the light flux available from a halogen MR16. MR16s of any variety have no business on the outside of a motor vehicle used (at all) on public roadways.

I disagree with that. I recently replaced two 35w GU10 halogen bulbs with 9w Epistar LED, and they are brighter and the light is much more pleasant to the eye.

 

[Alaric Darconville]

Great for interior design, bad for cars.

Leave the MR16s to the track lights and off the dirt track.

 

[guy48065]

Great for interior design, bad for cars.

Please don't make broad statements like that without qualifying it. An MR16 is a bulb with integrated reflector. They run on 12V. Trailtech and other manufacturers make excellent lighting systems that use it so what in particular makes this inappropriate for mobile use?
Do you also recommend readers to not use automotive bulbs in their landscape lighting?

 

[Alaric Darconville]

Poor vibration resistance, high amounts of heat, and the fact that the reflectors are essentially like a flashlight-- very simple, without any shaping of the beam other than tight spots (as tight as 8 degrees), or wide floods (up to 60 degrees) (and with varying amounts in between)-- but without any control of upward or sideward glare.

The GU10 is not a 12V bulb, either (and has a different base so it's not interchangeable with the low-voltage bulbs), and has a much more fragile filament.

Certain automotive bulbs can be used in landscape lighting, for example, the 921 (a 12.8V, 1.41A miniature wedge bulb) fits in most of those "Malibu" low-voltage systems. Depending on where you get the bulbs, it may be cheaper to use the automotive ones than the Malibu-branded bulbs. Was there a point to that question?

 

[Alaric Darconville]

As far as the 9W LED devices referred to in a previous post, the luminous efficacy might be quite high right out of the box, but they will quickly degrade without proper thermal control. They also only put out 430lm. Assuming a modest 26lm/W luminous efficacy for the halogen bulbs, a 35W MR16 will emit 910 lumens.

 

[guy48065]

Poor vibration resistance, ...

Is this an assumption or is there a specification for it?

 

[AnAppleSnail]

Is this an assumption or is there a specification for it?

Well-known phenomenon

It takes special design (And often hurts light output) to make vibration-resistant filaments.

 

[guy48065]

My question is specific to the MR16 durability. Is it an assumption they won't last because it's main use is as an indoor bulb, or is there data to support the statement? There must be a MTBF spec for the bulb.

I ask because I used this bulb as an aux. flood off-road for 3 years and never had to change it out. It had good output, stayed clean & corrosion-free due to the sealed reflector and made an excellent flood for such a very small form factor.

 

[iroc409]

My question is specific to the MR16 durability. Is it an assumption they won't last because it's main use is as an indoor bulb, or is there data to support the statement? There must be a MTBF spec for the bulb.

I ask because I used this bulb as an aux. flood off-road for 3 years and never had to change it out. It had good output, stayed clean & corrosion-free due to the sealed reflector and made an excellent flood for such a very small form factor.

I don't have a dog in this fight but it might be hard to prove a negative, because what they are saying is that it's not designed for that service. MTBF figures, for most devices I've seen, are calculated for a device's standard operating range. Generally devices are engineered for the application, and without significant testing you can't really say for sure it will work in another environment/application.

There is some data in applications like weapon lights (anecdotal, but enough to be "proven") for example. Using a flashlight not designed for firearm use on a firearm usually ends up in premature failure. The "impact" of firing often destroys the bulb and/or LED unit.

 

[alpg88]

check out this thread, it isn't in english, (thou there is a translator on the site), just look at picks.
bridgelux led based custom off road light, 13000lm

 

[guy48065]

How do you get 6000lm each from a 12V source??

Check out the youtube test run--amazing lights!

 

[-Virgil-]

I'm seeing lots of foreground light, not a whole lot of spread, and not much reach. Makes for an impressive video, but does not appear adequate for the speeds they appear to be hitting.

 

[TEEJ]

I'm seeing lots of foreground light, not a whole lot of spread, and not much reach. Makes for an impressive video, but does not appear adequate for the speeds they appear to be hitting.

That's how it looks to me too.

The guy who held the range sign was just able to be spotted about 50 meters away...hardly earth shattering.

I think putting a 4" Zebra Light SC600 on the roof would have worked about the same, but with a little better spread and throw.



On the flip side, they didn't appear to actually be going that fast either...so it MIGHT have been adequate for their speeds, and/or, they were slowing down because they would otherwise overdrive their line of sight.

 

[guy48065]

Tough crowd
I can't read russian but I wonder if the reflector was carved out with a ball mill or is a purchased item. It doesn't look especially smooth or reflective. As a prototype I think it's pretty amazing. I'm unfamiliar with LED arrays--wouldn't it be hard to get a precise pattern from a small reflector with such a large light source?

 

[kingofwylietx]

You can buy Bridgelux reflectors. I would have to watch the video again, but IIRC, it looked like a standard purchased reflector. That would be much easier than making your own. It's apparently fairly easy to piece together purchased LED components and drivers, but I think it would be difficult to mill a precise reflectory and get it coated. Can you imagine how many 'tries' it would take before you saw the results you wanted? I'm sure that I could approximate a reflector, but he devil is in the details of fine tuning it.

 

[alpg88]

the reflector is sold at digikey.

 

[babongo]

Returning to the OP's original objective, perhaps an affordable solution would be to pair the housings mentioned above by chachung with a constant current drop-in module like DX SKU 100483 , assuming that a thermal bridge could be established between the module and the housing. A lower output off the shelf option is DX SKU 132601.