Constant voltage drivers are becoming more popular lately. They’re safer, flexible, and often cheaper than their constant current counterparts, but it can be a little more difficult to pick the right CV driver for your system than it would be for a CC build. Don’t sweat though, it’s really not very hard. All you need is an understanding of how parallel wiring works and to know how to manipulate forward voltage and current numbers using data sheets or product simulators.
Below are the steps to take to find a suitable constant voltage driver. Continue reading
In my previous test, I ran a couple of Vero 18 COBs at their typical rated current to see if I could get either of them to go into thermal runaway. Over the 4 hours I tested them, each of the COBs ended up pulling an additional ~50mA each than what they started at, but stabilized at this level. Curious to see if I could get one of my COBs to go thermal, I decided to take another stab at this and hit a couple different chips with considerably higher currents than they’d normally be run at.
Here are my results:
My bucket peppers are looking pretty healthy. It’s interesting to see how the 2 types of plants look so different now – it’s easy to tell the Scorpions from the Brainstrains, but it’s difficult to tell which are 3000K and which are 5000K plants. At this point, they are still nearly indistinguishable. The 3000K Scorpion has more bulk to it than its 5000K counterpart, but the Brainstrain plants are very similar in size and structure.
I think the timing for Spring is going to work out very nicely for these plants; usually, I’m moving plants outside in the first week of June. These guys should have an excellent head start on producing peppers before it gets too cold again at the end of August. I really shouldn’t even be thinking of this summer coming to an end yet though! Spring is still a ways away so I’ve got plenty of time to enjoy scooping frozen dog shit off my barren tundra wasteland of a lawn before the birds start singing and the icicles start melting.
After playing with my new HLG-100H-36A constant voltage driver for awhile, I conducted a little experiment this weekend to see if I could get either of my Vero 18 COBs to go into thermal runaway. Thermal runaway can happen in constant voltage systems where the current is allowed to vary, while the voltage is held steady. As the COB LEDs heat up, their properties change, and this causes them to draw more current, thereby heating them up further and drawing even more current. Eventually, the LED can destroy itself due to this cycle of drawing more current and heating.
Quite often, you’ll see recommendations to add a resistor in series with your LED if you’re using a constant voltage driver. I wanted to see if I could get away with skipping these resistors and simply running my COBs hooked up directly to the driver.
Today, our cold snap finally broke and it warmed up to a reasonable -12 or so. It’s supposed to be above 0 degrees this weekend, so I’m pumped. When it was a chilly -30 the other day, I finally decided to move my grow tent up into my office where it’s nice and warm and the plants have already responded without a doubt.