DIY Refugium LIght

[reefinnewb]

Built a refugium light and after about a minute of use, the lights start blinking on and off very consistently. Here is what I used. I'm wondering if the driver hasn't met the minimum voltage..

 

http://shop.stevesleds.com/5-12-LED-3W-LED-driver-8794102450.htm

 

1x http://shop.stevesleds.com/Hyper-Violet-V30-8794102498.htm

 

4x http://shop.stevesleds.com/3-Watt-Cool-White-Epistar-CLEARANCE-8794102456.htm

[evilc66]

By the numbers, you should be ok, but you are probably right on the bottom edge for the driver voltage. It's possible that the lower voltage limit might not be consistent from batch to batch due to part tolerances for the driver, and it may be a little higher than the 15v that's advertised on the site. Easiest way to see is add another LED and see if the blinking continues.

[reefinnewb]

Extra led fixed it. However now it gets blazing hot. Is there a 40mm fan that can run off of this driver in conjunction with the 5 leds?

[evilc66]

Nope. Fans are constant voltage. Your driver is constant current.

 

Define "blazing hot"? Is it hot enough that you can't touch it? If so, I would get rid of the driver in a hurry and get something better quality. These Chinese drivers can be a crap shoot, especially seeing as you already had an issue with the minimum voltage limit. Steve's page claims that it's 85% efficient. With that in mind, at worst, it should get just mildly warm. These drivers are intended to be enclosed, so they shouldn't get as hot as you are describing.

 

I know you already put the time and money into that driver setup, but I would get a cheap 24v power supply and a 700mA LDD-HW driver. It will be far more reliable, and later on, you could make it dimmable (leave the dimming pin/wire disconnected for full output).

[reefinnewb]

I'm sorry I should have specified. The heatsink gets blazing hot. The driver is barely warm.

 

So to use a fan I'd have a second ac adapter..hmm

[evilc66]

What's your heatsink?

[reefinnewb]

3.5x4.5x1"

 

Enclosed much like the IM refugium light.

[evilc66]

Enclosed completely? Does the enclosure have venting like the IM light?

 

Really, for how much power you are running, you should have the fins of the heatsink exposed to ambient air, not enclosed. The IM fuge light is only running 6W, and the case has perforations on the back to let the heat escape. You are running almost three times the wattage, and three times the heat. A heatsink of the size you are running is capable of dealing with the heat, but only if it's exposed.