120W of Retina-Searing LEDs for only $6.76 [VIDEO]
Ride along as I harness the light (and manage the heat) from 120 Watts of LEDs to make a grow light for a hydroponics experiment.
This is a fun build because the real problem isn't electrical, it's heat dissipation.
If you like this, check out the Facebook group at https://facebook.com/groups/wehackhardware. Search for my video called "Tennis Ball Mayhem"...bet you've never seen a ball-drop like this before. :)
For this grow light, these are LED COBs, which stands for Chip On Board. This is relatively new technology where the semiconductor is mounted directly on a PCB without packaging. Then the semiconductor area is flooded with some phospher-loaded silicon to make white light.
Another thing that makes these particular COBs interesting is that they are "driverless". Or, rather, the driver is built-in. So these hook directly up to 120VAC. There's no need for an external current source, as you would use for regular LEDs.
You might think it's just a matter of hooking up AC and you're done. Nope. Heat is the problem here. In this video I start small and step up to running 120 Watts of LEDs, carefully trying things and monitoring temperature for safe limits and to ensure long life of the unit.
And I did the whole thing without roasting any electronics or burning myself!