MrNaz
Enlightened
I've just put together what will likely be the basis of my first flashlight project. I wanted to get an idea of what output I can expect, what sort of voltages and currents I'd be working with and just generally get a more comprehensive feel for working with LEDs.
This is what I put together:
That's just a trio of Cree XRE R2 WGs in series with these optics on them:
http://www.dealextreme.com/details.dx/sku.1920
Those optics are SO easy to use. They fit perfectly on the Cree lamp assembly, focusing perfectly. I did not need to fidget or fiddle with them to get them all shining on the same spot.
Firstly, I've realized how much of a difference good optics can make. Secondly, I've come to appreciate just how much heat such an array like this puts out. I have 3 SSC P4s in my dive light, with a far smaller heat sink, but they don't heat up anywhere near as much, probably due to not being driven as hard. Direct driving these from that 3 x RCR123A cell in the pic makes the heat sink too hot to hold within 30 seconds.
A multimeter reports that they are drawing 900mA, but that doesn't sound right to me. Surely, with nothing regulating the current, those batteries should be able to deliver more than that? I'd like to have 1A delivered to the LEDs. If a fully charged set of 3.7v Li-ion batteries can only deliver 0.9A, what arrangement can I use to deliver 1A each to a set of 4 LEDs? Do I have to increase the voltage of the battery pack and then use a driver? Even so, with 900mA, these babies are bright.
I want to build a light based on these LEDs and optics for scuba diving. I was thinking an array of 4 of them. Perhaps I could arrange them into 2P2S arrangement, and use a 7.2v battery pack made out of, say, 2 18650 batteries. If I direct drive from that arrangement, pulling 2A in total, with decent 2400mAh batteries I should be able to get about 2 hours of light, with 1 hour at or near full brightness. Does that assumption sound reasonable? Or should I be using a driver of some kind?
Also, how hard is this project going to be for me, given that I don't have access to anything other than a dremmell? Is a scuba torch even possible without the use of precision tools and CNC gear?
This is what I put together:
That's just a trio of Cree XRE R2 WGs in series with these optics on them:
http://www.dealextreme.com/details.dx/sku.1920
Those optics are SO easy to use. They fit perfectly on the Cree lamp assembly, focusing perfectly. I did not need to fidget or fiddle with them to get them all shining on the same spot.
Firstly, I've realized how much of a difference good optics can make. Secondly, I've come to appreciate just how much heat such an array like this puts out. I have 3 SSC P4s in my dive light, with a far smaller heat sink, but they don't heat up anywhere near as much, probably due to not being driven as hard. Direct driving these from that 3 x RCR123A cell in the pic makes the heat sink too hot to hold within 30 seconds.
A multimeter reports that they are drawing 900mA, but that doesn't sound right to me. Surely, with nothing regulating the current, those batteries should be able to deliver more than that? I'd like to have 1A delivered to the LEDs. If a fully charged set of 3.7v Li-ion batteries can only deliver 0.9A, what arrangement can I use to deliver 1A each to a set of 4 LEDs? Do I have to increase the voltage of the battery pack and then use a driver? Even so, with 900mA, these babies are bright.
I want to build a light based on these LEDs and optics for scuba diving. I was thinking an array of 4 of them. Perhaps I could arrange them into 2P2S arrangement, and use a 7.2v battery pack made out of, say, 2 18650 batteries. If I direct drive from that arrangement, pulling 2A in total, with decent 2400mAh batteries I should be able to get about 2 hours of light, with 1 hour at or near full brightness. Does that assumption sound reasonable? Or should I be using a driver of some kind?
Also, how hard is this project going to be for me, given that I don't have access to anything other than a dremmell? Is a scuba torch even possible without the use of precision tools and CNC gear?
