Searching for a 3 or 5 watt Luxeon Led for FX5

[darkplaces]

I have invested in my FX5 which has served me well over the past couple of years. Recently I changed the pilot builb to a Luxeon 1.5watt led which gives nice even light for about 20hrs or so, brought from HnK.

I am searching for a 3 or a 5 watt luxeon screw builb like the 1.5 I have already.

I'v searched all the normal caving shops and LED shops for this but no joy. I am thinking of modding the head lamp.

Please keep an eye out for such a thing and let me know if you spot anything.

Thanks.

 

[Stu]

Looked for the same thing. Couldn't get a screw in 3 or 5 watt led. However, I've come close to perfecting using an old screw in bulb, breaking the glass, moulding super glue inside and setting an led onto the top. Requires some fiddle with wire and solder but you can get cheap leds from ebay to practice with. Some sites I've visited claim to be able to concoct any config. you wish. Probably the same sort of sites you've seen but I will try to re-find them for you.

P.S. All may mates say why bother... but there is something, and I think Sam T will agree, to a home spun mod. Sense of satisfaction... and the biggest kick ass light that will last for years!! Bwhahaha!!!

 

[darkplaces]

Kick ass light

I'v blown '3' 6/10watt filament builbs I know the LEDs are more bashproof and give off a nice light. Hmm I can solder from 20ft :twisted: so I think I will have to start modding.

 

[darkplaces]

I'v brought a couple of 5watt star Luxeons;
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=66954&item=7508702643&rd=1&ssPageName=WDVW

I'm going to try and mount one on a builb (with the glass removed) so it can be removed & focused as required. Max volts is 8.31 so it should be ok for the FX5 were a 7volt 1.5watt Luxeon works ok.

Datasheet: http://www.luxeon.com/pdfs/protected/DS40.PDF

 

[Stu]

I'v brought a couple of 5watt star Luxeons;
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=66954&item=7508702643&rd=1&ssPageName=WDVW

I'm going to try and mount one on a builb (with the glass removed) so it can be removed & focused as required. Max volts is 8.31 so it should be ok for the FX5 were a 7volt 1.5watt Luxeon works ok.

Datasheet: http://www.luxeon.com/pdfs/protected/DS40.PDF

I think it may have been Dave H (the brainiest man on cavetalk) who pointed out that some major heat sinking may have to be introduced into the system. I was only trying of 3.6 v (3*AA) and wasn't too concerned.

Just a thought for you, though you sound like you have it sorted.

How have you removed the LED from the backing?

 

[darkplaces]

Heat oh bugger... I'll have to see how hot it gets.
I havent got the units yet but I was thinking of leaving the star-luxeon intact, soldering leads from the right bits of the screw-builb-bit then superglueing the star ontop of the screw-builb-bit. Or I could superglue it to the reflector with leads connected to the power screw points inside the head lamp. If I knaker it I just have to buy a new reflector no biggie.

 

[Dave H]

Watch out when mounting Luxeons! Neither the aluminium backplate of the star, or the slug of the actual LED if you remove it, are electrically neutral. i.e. don't connect them to the battery + or -.

Stu, I like your new avitar, but what had you been eating/drinking the night before to have that effect? And I'm sure that I can't be the brainiest!

If you're trying to get light out of the Luxeon, you'll have to use 4 new AA's in order to get a reasonable voltage drop. I think the minimum is supposed to be around 5V, so you might have to use 5*AA to get a reasonable output.

 

[Stu]

Watch out when mounting Luxeons! Neither the aluminium backplate of the star, or the slug of the actual LED if you remove it, are electrically neutral. i.e. don't connect them to the battery + or -.

Stu, I like your new avitar, but what had you been eating/drinking the night before to have that effect? And I'm sure that I can't be the brainiest!

If you're trying to get light out of the Luxeon, you'll have to use 4 new AA's in order to get a reasonable voltage drop. I think the minimum is supposed to be around 5V, so you might have to use 5*AA to get a reasonable output.

Was playing about with a little widget called a linverter (www.linverter.com funnily enough). Don't really understand it but my sparky brother says it steps up the voltage. Seems to work.

 

[Stupot]

Maybe of some use ?

http://w01-0504.web.dircon.net/acatalog/Bulbs.html

Select LED Modules


Stu

 

[Stu]

Maybe of some use ?

http://w01-0504.web.dircon.net/acatalog/Bulbs.html

Select LED Modules


Stu

Purchase!!? Off the shelf!! No no dear boy simply not good enough! Far too simple a proposition!!!

Think they may be the 1.5w versions.

 

[darkplaces]

Cheers Stu and Brainy Dave,
Yeah that one you point to Stu is the 1.5watt version which is ideal for a pilot light, oh if only they had a 5watt screw type i'd snap it up.
http://w01-0504.web.dircon.net/acatalog/7V_1_5W_Luxeon.html

For the power I'm using the 6/7volt battery from my FX5 so i'll have plenty of power. Once I get the modules I try and document the conversion for everyone.

 

[Stu]

Cheers Stu and Brainy Dave,
Yeah that one you point to Stu is the 1.5watt version which is ideal for a pilot light, oh if only they had a 5watt screw type i'd snap it up.
http://w01-0504.web.dircon.net/acatalog/7V_1_5W_Luxeon.html

For the power I'm using the 6/7volt battery from my FX5 so i'll have plenty of power. Once I get the modules I try and document the conversion for everyone.

Excellent Smithers....!!

 

[Stupot]

On the subject of converting SpeleoTechnics kit, brings me on to just how shite the build quality of my 14 LED headlight is.

Now i know this is an ongoing gripe and there is many a post on this site,
but when you shed out around 190 golden nuggetts for a light you don't expect the water to "piss" in every hole within minutes of being underground, the internal wires to get crushed when you tighten the outer ring, and the battery casing to be loose letting more water in.

The reason for this is that i spend 2 hours today with a tube of silicon addhesive filling every hole and contact, resealing the battery case, and rewiring the head so that all cables are out the way :evil:

Like many of you say "a good light, but god damn awful design and build"

Paddy over.

Stu

 

[Dave H]

Was playing about with a little widget called a linverter (www.linverter.com funnily enough). Don't really understand it but my sparky brother says it steps up the voltage.

I had a quick look at the kit photo' on the site you quote. A couple of transistors, ans some capacitors, resistors, and inductors. Looks like a simple boost converter. Cheap and simple, it will do the job, but unless the design (and build) is really excellent then up to 20% of the power could be lost in the conversion. With a 5W Luxeon attached, I wouldn't be surprised if the transistors didn't get very warm and go bang. (The package type in the photo' doesn't conduct heat very well, and the by-product of the inefficiency is heat!)

For a more efficient solution you need to go for an IC based solution where the (many) transistors (and most of the resistors) are in the chip, and the better component tolerances that allows, will give around 95% efficiency.

I get the feeling that I ought to get a couple of these 5W Luxeon's, design an efficient supply from components that amateurs can easily buy, and put the design on the forum. But don't hold your breath for it – I'll check if there is some-one supplying kits for a small price first, as I don't want to ruin things for them.

 

[darkplaces]

Do you think I need a 'linverter'? Or can I just connect the LED to the battery. Am I right in thinking this unit keeps the light stable regardless of the power left in the battery. I kinda like the dimming effect of a light when the battery is going low, kinda lets me know when to head out and/or to double check my backup works.

 

[Stu]

Do you think I need a 'linverter'? Or can I just connect the LED to the battery. Am I right in thinking this unit keeps the light stable regardless of the power left in the battery. I kinda like the dimming effect of a light when the battery is going low, kinda lets me know when to head out and/or to double check my backup works.

Not an expert by any stretch (Dave's your man) so wouldn't like to say if you need one. It boosts the voltage at the expense of amp hours of course but there is a fade so you don't habe a light then no light scenario.

There is some inefficiency I believe in this system but I couldn't explain it. I liked it because I could run 7 LEDs from less voltage (thus batteries) and still get an adequate light. My perspective was slightly different to yours. I wanted a good light for little in the way of battery pack size. Running the biggest available (correct me if I'm wrong) commercial cave battery leads me to your wanting the brighst mutha of all lights!!


Aaagh I can't see...........

 

[potholer]

From the voltage/current curve on the Luxeon V datasheet, if running from a nominal 6v (5*NiCd) battery, there could be a pretty serious variation in output between a fully-charged battery and a used or part-used one.

Also, the possible variation between individual LEDs in terms of their voltage/current characteristics could make a simple direct-to-battery or resistor-limited design problematic. Taking some voltage/current readings for an individual Luxeon device might be useful. Alternatively, the binning/labelling guide:
http://www.lumileds.com/pdfs/AB21.PDF
can help get an idea of the voltage characteristics of a particular device from the codes on the back of the Star.
I find it quite useful for the 3W Stars I use in my lights. It's a pity the regular emitters aren't somehow labelled [more nearly] individually.

With an FX5, taking some voltage readings while running a ~5W halogen on a fully charged, part used and well-flattened battery might give insight into whether fancier electronics would be useful, or even required.
If you happened to have a particularly sensitive 5W LED, a step-up converter may be essentially useless. If you had a particularly insensitive one, you may need a step-up converter to get worthwhile light output.

 

[darkplaces]

YAY the Luxeons arrived today. I'v soldered red/black leads on one and attached it to a 6V 4Ah lead acid battery and it runs good, nice and bright, I wonder how long it would last on this battery?.

Attached it to the FX5 and BOY was it BRIGHT :shock: I had the wires crossed (not bare wires but insulated ones and after a while they started to smoke and I smelled burning, the luxeon got rather hot so I guess I need some heatskink arrangment.

Even with just the 6v 4ah lead acid battery its hot but just about coping I think, snif, isnt smelling yet...

Any clever do da info anyone knows would be handy.

 

[potholer]

You'll certainly need heatsinking. Even running 3W Luxeon Stars at 1W, they would get hot if not heatsinked (or should that be heatsunk?)
In theory, you should expect something like 3-4x the heat from a 5W luxeon compared to the heat that a 5w halogen would generate - the halogen dumps most of its waste heat as infrared radiation from the hot filament, but LEDs don't have that option, so all their waste energy goes into getting them and their surroundings warm.

Epoxying Stars and Emitters (run at up to 1W) onto thin aluminium sheeting works for my lights, but I use an odd arrangement where the heat can easily find its way to just behind the headset glass. If you're going to have a metal plate completely *behind* the reflector, it might be less efficient at dumping heat. The sheeting I use has a thin paint layer on one side, so gluing to that side removes worries about non-insulated parts of the LEDs making unwanted connections via the heatsink.

I use JB Weld epoxy to attach my devices to the aluminium sheet - it's rated to something like 300 degrees Celsius (rather than the sub-100 degree rating for Araldite), and seems fairly heat-conductive (possibly due to having a fair amount of metal in the filler). It's an excellent all-round slow-setting epoxy, and is also much easier to wash off fingers with soap and water than Araldite is. Rather harder to find than Araldite, and slightly more expensive, but worth getting hold of if you come across any. RS components sell it, as do some independent car-care shops..

Just out of interest, what's the 5-letter bin code on the back of your 5W Stars (top-left letter grouping)

 

[darkplaces]

Cheers Pot..
5 letter code top left 'UX1TW' whats that mean.
Since my last post (5:43 pm) its now just past 1am and the LED is still glowing bright, connected to the same 6volt battery.