Super light ?

There they be. I'll wire it up tonight.

8bb897e9.jpg
 
yopappamon said:
There they be. I'll wire it up tonight.
Click to expand...

Where's the seeing eye dog and white cane? :shock: You really should plan ahead better... :roll:

BTW, I'm not all that impressed with the heat sink/fan. I'd start with something beefier. Monitor the temperature really closely. It only takes an instant for these things to turn into slag.
 
Also, a couple of the sellers mention that these can run 10 seconds without a heat sink... I wouldn't want to test that supposition.
 
Have you metered the actual voltage at the tabs and the current? The power supply may not be doing what they say. With 20W going in, a heatsink of that size should be getting warm.
 
That heatsink is a joke - I would be using a PC processor heatsink + fan off a P4 or something - these LED lamps are use at my local cinema for floolighting when they are cleaning (an they are also used around the railways) - they are VERY bright. They don't use the lens though, only the reflector.
 
texaspyro said:
Have you metered the actual voltage at the tabs and the current? The power supply may not be doing what they say. With 20W going in, a heatsink of that size should be getting warm.
Click to expand...

15.25 volts across the led. Seems about right for a 20w supply feeding a 25w led. If it's putting out it's rated current of 1300ma x 15.25v = 19.825w. The fan is drawing a little also.

Don't know what to tell you about the heat. It isn't getting hot, even the Led base plate isn't hot. I should leave it on for while and see if it builds up any heat. My watt meter is at work so I can't meter the amps.

I had the same thought about the heat sink, but it was cheap. I thought I would try it out and see if it was enough. Seems like it is.

mushymelon said:
Are you planning to test with the dc/dc?
Click to expand...
eventually. My bike is at my work so I'll have to wait until infix the wheel and get it home.
 
Well, the numbers don't quite add up but check out:

http://cgi.ebay.com/300W-White-15000LM-Lumen-Energy-Saving-High-Power-LED-/230557130509?pt=LH_DefaultDomain_0&hash=item35ae469f0d#ht_3519wt_1070

300 watt/20,000 lumen. Use it as a brake light and it should keep the tailgaters at bay...
 
Figured you guys may want a link to some LED drivers that would be good for 15w http://endless-sphere.com/forums/viewtopic.php?f=31&t=23307


Do you think 15w would be good enough for a bike Yopappamon? Kinda hard to tell how bright it actually is from a pic.
 
texaspyro said:
300 watt/20,000 lumen. Use it as a brake light and it should keep the tailgaters at bay...
Click to expand...
Sure, as long as their first instinct as a newly eyeless person with the deep deep tan is to slam on the brakes. :lol:
 
I bet it's a bitch scraping 300 watts off the back of that package. Very few CPUs draw that kind of power and they can take a much higher temperature than LEDs. When the price comes down an order of magnitude, I'll buy a couple and see.
 
Well, I have about 500 bucks worth of blinkenlights on the way... need to price a reliable seeing eye dog next.
 
LED lightbulbs for general purpose use are beginning to become usable. I took inventory of the bulbs in my house (and you wondered why I have a large closet that just holds spare light bulbs) to see what it would cost to go green:

68 x 75 watt BR40 $3000
57 x 75 watt BR40 on dimmers $2500
12 x 50 watt PAR20 $500
99 x 50 watt PAR20 on dimmers $4000
44 x 50 watt MR16, 12V on dimmers $1000
39 x candelabra bulbs on dimmers $300
3 x 3' fluorescent $100
2 x 2' fluorescent $50
8 x 60W Lumiline bulbs!

Turn 'em all on at once at watch 16 kw send the meter 'round and 'round at 2 bucks an hour. Gee, for only $11,000 I can get a cool fuzzy feeling about saving the planet. A little rational thinking says only 10% of those lights are ever really used. A little math says payback is actually around 1 year on those bulbs if air conditioning heat load costs are included ... might even make sense.
 
F Me! How big is that house! Here in Aus, it is illegal to sell filament bulbs (halogen is exempt - and stuff like fridge/oven bulbs) for home lighting, all you are allowed to use is compact fluroescents or halogen replacement bulbs.

I don't find the compact fluro's too bad but wonder exactly what the environmental cost will be - there are a lot of nasty heavy metals in them, with no recycling programme in place...
 
The house was originally built around 1920 and had a studs-up remodel about 10 years ago. The designer obviously had a photon fetish. A pretty good number of the bulbs are for artwork illumination and around 20% are outside. And, I found a few more bulbs tucked under some cabinets...

The US is also phasing out filament bulbs (yeah, like that's gonna happen). If I go LED, I'll keep my incandescent stash and wait for the price to skyrocket and make out like a black market bandit. Right now, the LED bulbs seem to be catching up to incancesdents but are still a little limp in the lumens. Those MR16 12V halogens are going to be hard to replace. They put out 900 lumens and the LEDs around 300.

I HATE compact fluorescent bulbs and would never use them. They are the biggest scam around. Enviro issues. Plus I'm an American. When I flip my switch, I demand ALL my photons NOW! Not after 15 minutes of warmup time.
 
texaspyro said:
LED lightbulbs for general purpose use are beginning to become usable. I took inventory of the bulbs in my house (and you wondered why I have a large closet that just holds spare light bulbs) to see what it would cost to go green:

68 x 75 watt BR40 $3000
57 x 75 watt BR40 on dimmers $2500
12 x 50 watt PAR20 $500
99 x 50 watt PAR20 on dimmers $4000
44 x 50 watt MR16, 12V on dimmers $1000
39 x candelabra bulbs on dimmers $300
3 x 3' fluorescent $100
2 x 2' fluorescent $50
8 x 60W Lumiline bulbs!

Turn 'em all on at once at watch 16 kw send the meter 'round and 'round at 2 bucks an hour. Gee, for only $11,000 I can get a cool fuzzy feeling about saving the planet. A little rational thinking says only 10% of those lights are ever really used. A little math says payback is actually around 1 year on those bulbs if air conditioning heat load costs are included ... might even make sense.
Click to expand...

Geez that's a lot of bulbs.

I'm gradually switching from CFL low energy bulbs to LEDs (having switched from filament to CFL around 15 years ago) and am learning about some of the quirks of LED lighting. It's a bit like the early days of CFL, with variable colour temperatures and somewhat misleading specs in terms of real light output.

One thing I have found is that some of the cheap Chinese MR16 units can be very good. I recently bought a batch of 38 LED warm white wide angle bulbs from ebay and was pleasantly surprised by both the light output and the colour temperature. On the other hand I've bought a bunch of supposedly "equivalent to 50W halogen" MR16 spotlight LEDs that are just dreadful.

The best LED thing I've built recently has been an over-the-shoulder reading light, using just a 1 watt Cree LED fitted with a diffuser lens. This sits behind my chair and shines a bright white light down towards my lap - it's transformed reading and close work for me.

Jeremy
 
texaspyro said:
When I flip my switch, I demand ALL my photons NOW! Not after 15 minutes of warmup time.
Click to expand...

All the CFLs I've bought in the last few years have been instant-on, in fact, in the case of the main lamp in the bathroom far too instant on for me in the mornings, I'd prefer a gradual warm-up first thing.

I know what you mean though, some of my old CFLs (which are now over 15 years old and still going strong) do take forever to warm up, plus their light output isn't particularly good, either.

Jeremy
 
Back to bike lights - I personally prefer HID to LED when dimming/blinking is not required. No color halos, uniform beam and efficiency is still a bit better than brand name LEDs. Got a trailtech MR11 lamp with integrated driver/ballast for my touring e-bent project for $80. Similar to this but with flood beam (p/n 3152-FX):
http://www.trailtech.net/3152-SX.html
Runs of 12VDC. It is pretty bright for anything but technical singletrack. Takes about 10sec to warm-up.
They also sell full kit (much more expensive) but most e-bikers just need a lamp and DC converter.
 
curious said:
Back to bike lights - I personally prefer HID to LED when dimming/blinking is not required. No color halos, uniform beam and efficiency is still a bit better than brand name LEDs. Got a trailtech MR11 lamp with integrated driver/ballast for my touring e-bent project for $80. Similar to this but with flood beam (p/n 3152-FX):
http://www.trailtech.net/3152-SX.html
Runs of 12VDC. It is pretty bright for anything but technical singletrack. Takes about 10sec to warm-up.
They also sell full kit (much more expensive) but most e-bikers just need a lamp and DC converter.
Click to expand...

Could you post some pics of your beam pattern at night for us.
 
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