Buying heatsinks from HeatSinkUSA

[zeroinverse]

Hi guys,
Since RapidLED is coming to our meetup in September, I want to buy a heatsink from Heatsink USA.

You can use the RapidLED version, but they don't really have a wide 48" version (only 1.5", which means I have to buy 4).

I think I prefer one "large heatsink" that is 48" long by 10" long (for my 4foot tank). This way, I get larger "heatsink mass".

http://www.heatsinkusa.com/10-000/

If anyone else also wants to order heatsinks, we can split the shipping cost.

Then I can bring up to the September meetup for pickup.

 

[northbay-reefer]

Having multiple heat sinks separated with air space in between help with the cooling too. Also putting the LEDs on separate strips gives you options to move then around to mix colors or other type of strip light. Just someting to keep in mind.

 

[zeroinverse]

@Tom, you're totally right.

I had considered doing separate "T5 replacement heatsink strips".
The only problem is they are less efficient at heat dissipation. I can't put a computer fan across a 48" by 1.5" wide aluminum finned heatsink.

I may be going overly conservative. I want a good heatsink so that passive cooling will already prevent early failure of LEDs. I plan to have active fan blowing to keep LEDs even cooler.

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I plan to replace 4 of my 8 T5HO bulbs with LED. With my layout, I was thinking a pair T5HOs in front, and a pair of T5HOs in back. Then the middle would be "4 tubes" of LEDs.

At this point, that either means 4 separate heatsinks or just one large 10" wide heatsink.
My light fixture is 18~20" wide by 48" long.
============

Would love to hear your thoughts & ideas.

 

[northbay-reefer]

If you want to use a fan, have you look at tubular heatsink like Steve's LED? I saw the same tubing heatsink at Home Depot and you can cut them to size and connect them together and slap on a fan at the end. The LED tend to give the disco effect so I am glad to hear that you are mixing T5s in with them.

 

[zeroinverse]

Tom,
I thought about the TUBE style... and realized there is one big problem with them.
If the fan fails, there is no backup/fallback. And tube heatsinks do not dissipate heat well passively. They need the air flow.

That means for small nano setups, may be acceptable since they have less LEDs, are shallower, etc.

But for my case, I don't want to risk a fan failing and taking out one or two of my 4 LED strips (depending if one fan cools one tube or two tubes).

That would mean 12~24 LEDs would fail.

So that is why I am considering "passively cooled" heatsinks with fan as "added cooling".

 

[northbay-reefer]

You got a point there.

My 72" LED strip that I built is only using passive and it is working just fine so far. Most of the companies that are making Strip lights are only using passive so you should be fine too.

At what current are you going to push these LEDs, 700-750 mA?

 

[zeroinverse]

Probably around that, or maybe up to 1A if I go RapidLED (since it can tolerate 1.5A).
What is your experience with your setup? 700mA already TOO much light?

 

[northbay-reefer]

700 is good enough maybe go to 1000, if you push it to 1.5 you will definitely have alot more heat. I am currently using 700ma and it is plenty bright.

The blue will max out at 1000ma, while the white will max out at 1500ma so unless they are on different drivers, you will have to push it on the lower end. I would definitely put them on different drivers.

 

[zeroinverse]

So is 700mA plenty bright and grows coral? Or just plenty bright? Just clarifying.

 

[northbay-reefer]

If you are running all blue then 700-750ma is perfect because blue max out at 1000mA, if you are running only white then I would run 1000-1100ma because white max out at 1500mA. Whether Corals will grow with these lights or not, all I can say is my blue LED strip is brighter and reach deeper into the tank than two T5s.

 

[zeroinverse]

Planning to order heatsink. Anyone want to combine an order? Not sure if they price shipping per heatsink or as a set. But thought I'd check with everyone.

Since we have the rapidled meetup coming up.