I have recovered the following data from Google's cache manually.
Please post any errors and corrections in a new post below.
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The format is:
Date, time, old postcount#, poster;
post data
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I will try to fix the CPF links in the next 2 weeks or until I give up in frustration. Can not do that and verify with CPF down.
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11-04-2010 07:03 AM #2 andersonEE
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Why are you over-driving them? They already aren't that efficient...seems like lowering the efficiency even farther for a few more lumens wouldn't be worth it.
Regardless, bridgelux are awesome...looking forward to the pics.
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11-04-2010 07:28 AM #3 egghead2004
Only running at 1.4 amp because the driver I have on hand. Spec sheet for the 802 neutrals show a range of 600mA - 2000mA, is 1400mA overdriving them? Would I be better off with 4 802s and a 1.05A driver? Then I would be pushing the meanwell over the 48V rating.
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11-04-2010 07:44 AM #4 andersonEE
Oh yeah, 1.05A is just the recommended drive current. As long as your heatsink can handle the extra power I'd say go for it. Especially since you already have the driver.
@1.05A -- 12.81 Watts and 79.6 Lumens/Watt
@1.40A -- 17.64 Watts and 73.7 Lumens/Watt
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11-04-2010 08:52 AM #5 egghead2004
whew, thanks. I'm still somewhat new to this and I thought i was overlooking something.
This is the heatsink
http://www.heatsinkusa.com/storename/heatsinkusa/Image-10502823.aspx
It has about 160 s/i surface per linear inch. I bought a 10" hunk of it and will be cutting it into 3 equal pieces of about 3 1/4". Should end up being 520 s/i of surface to dissipate 53 watts.
I can't wait to compare the two lights, my current one of eight 402s @ 700mA vs. three 802s @ 1.4A
AND I'll have 2 more 50+ watt heatsinks to build more lights, the neighbors are SO going to hate me when I get all these up in the yard and driveway.
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11-04-2010 12:15 PM #6 purduephotog
egghead2004 said:
whew, thanks. I'm still somewhat new to this and I thought i was overlooking something.
This is the heatsink -http://www.heatsinkusa.com/storename...-10502823.aspx
It has about 160 s/i surface per linear inch. I bought a 10" hunk of it and will be cutting it into 3 equal pieces of about 3 1/4". Should end up being 520 s/i of surface to dissipate 53 watts.
I can't wait to compare the two lights, my current one of eight 402s @ 700mA vs. three 802s @ 1.4A
AND I'll have 2 more 50+ watt heatsinks to build more lights, the neighbors are SO going to hate me when I get all these up in the yard and driveway.
I've got a totally massive heat sink that is even higher fin density that yours running at around 80 watts and forced air- it's ice cold to the touch.
I'm going to be adding another 40 watts to it as soon as I get some more time.
I'm also getting an number of Avago LEDs cheap enough that I may go for around 300+ watts on the heatsink... will be interesting to see how warm that gets.
As for the bridgelux, even a much smaller sink with the 402 should handle the heat load fine. I'm assuming you're using the 48V IP67 Meanwell CC driver? I think mine was 1.3A.
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11-04-2010 10:13 PM #7 egghead2004
I have a couple of Meanwell LP60s. 60 watt @ 1400mA CC.
I fired the three 802s up tonight, wow, intense. I just need a Dremel to route out little holes for the wires so I can glue the reflectors on, that will concentrate the light to a smaller and more intense beam. I almost want to buy 6 more 802s and two more Meanwells and have 9 of these suckers running on that monster heatsink, 160 watts of hurtin' your eyes light! But it will be better to spread them out to avoid shadows...and sunburn
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11-05-2010 06:22 AM #8 purduephotog
egghead2004 said:
I have a couple of Meanwell LP60s. 60 watt @ 1400mA CC.
I fired the three 802s up tonight, wow, intense. I just need a Dremel to route out little holes for the wires so I can glue the reflectors on, that will concentrate the light to a smaller and more intense beam. I almost want to buy 6 more 802s and two more Meanwells and have 9 of these suckers running on that monster heatsink, 160 watts of hurtin' your eyes light! But it will be better to spread them out to avoid shadows...and sunburn
Are you dremelling the reflectors? I did that with one of the bridgelux units (26V/320ma) and it worked nicely... although I did blanch about it. The biggest issue I ran into is I haven't found a source of 4-40 flat head low profile screws yet. I've got the lock washers and insulating washers, but I still have fat domed screws.
