Heatsinks for DIY LED lamps
- Thread starter SupraSPL
- Start date
Waiks
Well-Known Member
I'm making the move of 54w on actively cooled 32" x 2.08" heatsink usa profile to 30" x 4.85" profile.
So that's 2688cm surface area increased to 6000cm. I've never laser temped my sinks before, but theoretically, how much of a temp drop can one expect by increasing the surface area of the heat sinks by more than 100%?
I moved my thermometer up from the floor of my cab to canopy level. 90*f... No wonder the ladies weren't looking so good. Silly me for going off of floor readings. (81*f)
So that's 2688cm surface area increased to 6000cm. I've never laser temped my sinks before, but theoretically, how much of a temp drop can one expect by increasing the surface area of the heat sinks by more than 100%?
I moved my thermometer up from the floor of my cab to canopy level. 90*f... No wonder the ladies weren't looking so good. Silly me for going off of floor readings. (81*f)
Zulunature
Well-Known Member
Hi just wanting to confirm this heatsink 1 is big enough to handle
4 x CXB3590 3500K COBS @1400ma passively.
I'm pretty certain it can handle it and will probably only ever run them at around 1.05A.
If SupaSPL or anyone could confirm that it's good enough for passive I'd be grateful.
Hopefully this will give the Oz lads something that will allow for passive running.
Just want to say I've been lurking for a while and the threads on RIU are really informative.
Thanks to all the community.
4 x CXB3590 3500K COBS @1400ma passively.
I'm pretty certain it can handle it and will probably only ever run them at around 1.05A.
If SupaSPL or anyone could confirm that it's good enough for passive I'd be grateful.
Hopefully this will give the Oz lads something that will allow for passive running.
Just want to say I've been lurking for a while and the threads on RIU are really informative.
Thanks to all the community.
alesh
Well-Known Member
How long is the heat sink? 4x 3590s @56% would need at least 66cm of this profile if we are to follow 120cm^2/W_heat.
Zulunature
Well-Known Member
The Heatsink is 39.6 inches or 1000mm in length.
alesh
Well-Known Member
Then you're good to go. Even 2/3 of the length would be sufficient. What about more COBs?
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Zulunature
Well-Known Member
Thanks for that information as it confirms what I thought. I'm only running 4ft wide so can't see much point. Besides want to run as cool as possible with good spread.Then you're good to go. Even 2/3 of the length would be sufficient. What about more COBs?
Going to run 4 bars of 4 cobs over 5'6" x 4" area @ 1050ma should produce something worthwhile.
These threads have been a boon for diy building, mouser is out of the HLG185C1400B in aus. but jerry is good to go.
For the Oz lot it cost $175.00
Ronin-indi
Well-Known Member
ok so I want to set up a 4x4 passive. I need a little help with the heat sink calculation...
2x 240h-c1050b running 12x cxb3590s over three bars, like example 3 of growmau5's diy led vid 3.
he said 61% efficiency, so at @ 36w a piece x4 = 144w per bar. 39% of 144 is 56.16 heat watts.
56.16 heat watts multiplied by 17 in2 is 954.72in2... correct? or did I forget to take in to effect the earth's rotation
if this is correct then the heatsink usa 4.23 profile, 25.56in perimeter, at 38in would work and save me a little cash from the 5.88...
2x 240h-c1050b running 12x cxb3590s over three bars, like example 3 of growmau5's diy led vid 3.
he said 61% efficiency, so at @ 36w a piece x4 = 144w per bar. 39% of 144 is 56.16 heat watts.
56.16 heat watts multiplied by 17 in2 is 954.72in2... correct? or did I forget to take in to effect the earth's rotation
if this is correct then the heatsink usa 4.23 profile, 25.56in perimeter, at 38in would work and save me a little cash from the 5.88...
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iceman3000
Well-Known Member
Hello to all..
i have now read 30 pages of this thread from the end back to page 50ish and my brain has been damaged at this point.
i'm look for a straightforward answer
(1) cxb 3590 3500k 36v @ 50 watts (hlg 240 1400c 5 per)
what is the best heatsink passive cooling size in inches please and square or round
as i'm looking to put them on a frame 5x5 25 total
any help would be much appreciated
i have now read 30 pages of this thread from the end back to page 50ish and my brain has been damaged at this point.
i'm look for a straightforward answer
(1) cxb 3590 3500k 36v @ 50 watts (hlg 240 1400c 5 per)
what is the best heatsink passive cooling size in inches please and square or round
as i'm looking to put them on a frame 5x5 25 total
any help would be much appreciated
Fastslappy
Well-Known Member
I got some heat sinks , can someone look @ them
can ya give a opinion on usefulness of these with some 3950's active cooling
I started a thread on my build the pix of sinks are @ 1st posts
https://www.rollitup.org/t/slappys-perpetual-led-hack-discussion.894986/
can ya give a opinion on usefulness of these with some 3950's active cooling
I started a thread on my build the pix of sinks are @ 1st posts
https://www.rollitup.org/t/slappys-perpetual-led-hack-discussion.894986/
Fastslappy
Well-Known Member
let me guess the last posts here the 3 of us all bought 3950's today
ttystikk
Well-Known Member
Gotta love a de facto standard!
iceman3000
Well-Known Member
i know its sooooo sick to ask what i did! i'm so lost as i had a great mock up of a fan cooling bar perfect.. i now have talk my self into passive cooling for 5 reason's
so to keep it simple 1 cob 1 sink cxb3590 36v i think or 32v something like that @50w, but i am one that will go over it and over it before i pull the trigger just want to know this for my own pice of mined and cost has no play on it not looking for the cheap way if the sink cost what it cost, it is what it is.. if you have watched the diy talk this week by GG that's what has started me down this road
thanks iceman3000
so to keep it simple 1 cob 1 sink cxb3590 36v i think or 32v something like that @50w, but i am one that will go over it and over it before i pull the trigger just want to know this for my own pice of mined and cost has no play on it not looking for the cheap way if the sink cost what it cost, it is what it is.. if you have watched the diy talk this week by GG that's what has started me down this road
thanks iceman3000
Greengenes707
Well-Known Member
You're going for the 4x4(16 cob) bar set up...4 bars with 4 cobs on each. A great build and will do just what you are lookign for.
-Each bar will have four 48w 3590's running in the 55% range. So your looking at 21.6w of heat out of each cob...times four cobs...give 86.4w of heat for each sink to dissipate off.
-We were talking about the 5.88 profiles...great for either active or passive and favor passive. each inch of that profile has ~260cm2 of surface to cool. Recommended is around 110-120cm2 per watt of heat for passive cooling.
86.4heat watts x 115cm= 9936cm2 needed
9936cm needed divided by 260cm2 per inch heatsink = 38 inches of 5.886 profile heatsink is needed per four 3590's at 1400ma for passive cooling.
I would go with 40" to 45" bars to give you extra spread and extra cooling.
You could connect 4 bars together with some aluminum frame or L's and have only 4 big panels to deal with in a 10x10 room.
No questions asked that will replace a 1000w's of hps, gavita included.
iceman3000
Well-Known Member
LOL i know i could count on you to chime in. was looking at the round ones you had on the new build as i was think to cut the wight and the inclosure as i'm not looking at the whole ul listing thing from the retail side.. frame them all together each fixture pulling less then 6 amps as amps is my problem will fill you in when we talk np..
keep up the great work
thanks again
frica
Well-Known Member
Anyone know if http://www.deltourheatsinks.com has a minimum order quantity?
Fastslappy
Well-Known Member
anyone understand/know heat transfer theory ??
what's a better sink to attach those Mars2 finned heat sinks to ? I'm doing a bar build using AL flat bar stock about as wide as the Mars2 sinks
starting with the flat AL stock to add to those mars heat sinks to ??? acts as a cob mount plate as well
3/8" or 1/4" or smaller .133 is a size i see alot as reuse or cut-off sections cheap $
I'm thinking .133 is lite in weight but is thicker better for dispersion of heat ??
thick 1/4" is stiff but heavy
CXB3590's pushed @ 50% # of cob on each bar & placement yet to be as this needs attn 1st
what's a better sink to attach those Mars2 finned heat sinks to ? I'm doing a bar build using AL flat bar stock about as wide as the Mars2 sinks
starting with the flat AL stock to add to those mars heat sinks to ??? acts as a cob mount plate as well
3/8" or 1/4" or smaller .133 is a size i see alot as reuse or cut-off sections cheap $
I'm thinking .133 is lite in weight but is thicker better for dispersion of heat ??
thick 1/4" is stiff but heavy
CXB3590's pushed @ 50% # of cob on each bar & placement yet to be as this needs attn 1st
Led Newbie Oz
Member
Correct me if i'm wrong but this H/S should passively cool one cxb3590 @ 50W
http://www.cutter.com.au/proddetail.php?prod=cut2489
@ $17 each you could passively cool twelve 3590's for $204, which seems like the cheapest option so far for those of us down under.
May solve the Aus passive cooling issue?
tstick
Well-Known Member
I stumbled across that site and video by accident. Forgive me for my ignorance in not being able to answer your question. I was hoping that some of the "in-the-know" people would chime in.
klx
Well-Known Member
Yep the LSB9980 passively cools 30W so that should be enough for 3590s @ 1400 or less.
None in stock atm though...