Thanks, glad it helped. Hope your build is going well for you. Looking forward to seeing it wired up. If you got questions just lemme know
It is now all done and ready for install in the tent. Finished up installing the quick connects from the driver to the LED light bar.
Sweet little rig.
Now let’s watch and see what it can do.
With the appropriate eye wear, of course.
Like a glove…Light is now installed in the veg tent. Frame profile is perfect for this tent. I’m very content with the design. The pictures are with the lowest light setting. I’ll be testing this light for a couple weeks in operation and report back.
Outstanding build thread! Thanks!
Im a month into my first ever grow, and just ordered 6 strips and a driver. I have 2ea Northern Lights and 2ea CBD critical in a 2’x3x4’ tent (actually about 7 sq ft total. Im going to scrog when they get tall enough. Im using about 500 watts of CFL’s now and thats not working as well as I hoped. The plants are bushy and look healthy, but still kind of short. Plus messing with all these individual bulbs and the heat is a pain.’
Im going to do something similar to what you did including keeping the driver outside the tent so I can reach the dimmer easily. The only thing I will do differently as far as wiring is I plan to run 14 ga wire from the driver to the fixture, then branch off 18ga to each strip. That will help a hair with voltage drop. Plus, I have the wire on hand
Almost forgot the question I wanted to ask… I have my fan mounted near the ceiling of my tent, blowing down. Its a regular, cheap 20". 3 speed, box fan. I will mount the strips in a frame like yours under that fan.
I notice you used actual heatsinks to mount your strips on. Is that necessary?
I was hoping to get by with using some 1.5" wide, hardware store aluminum U channel. It will be three rows of two strips each. All three rows will be under the fan to one degree or another.
Thanks again for a great build thread!
How much wattage per strip are you going to run?
69% power or below with u-bar and active cooling like your describing will be fine. Anything over 33w per strip should have some kind of heatsink mounted.
The heatsinks are only $10 each, pretty cheap insurance. U channel will not be much less…I actually considered this as well but decided to get the heatsinks.
Thanks for the tips guys! I was actually thinking of starting out at around 30 watts/strip while Im still in veg, then crank it up for flowering.
I already have almost enough scrap aluminum channel left over from another project, so I will start with that and run some tests and see if I need to go with real heatsinks or not.
have you grown any with them i have a 60x60x180 tent and wanted to make something similer with the 240w meanwell driver with 4 solstrips and 2 red blue and turn it down a bit any advice
You won’t regret it. Go for it!
If you need quantative results to go on, just check out my cab thread, I’m not finished with flower but they are doing better than 400w hps did with less wattage.
I have a question for you about this part of your post. Its entirely possible I have a misunderstanding about how LED’s and CC/CV power supplies work, so please correct me as needed. I have been messing with electronics stuff for many decades as a hobby, but I am NOT an electrical engineer and Im a long ways from an expert on LED’s
I’m wondering how you got the current and voltage numbers at the end of that quote. I follow the math you used, but I didnt think that was exactly how CCCV drivers and LED’s work together.
Im trying to predict what power usage Im going to have at various settings with the Solstrip/driver parts I just ordered, so thats why I am asking.
Its been my understanding that these power supplies are constant voltage and constant current. Every similar CCCV power supply I have used in the past could be operated in both modes depending on how it was used. I cant find a user guide for the Mean Well’s that goes into the details of how to make the adjustments, so I am just guessing here, but what I did see does say it has a CC “voltage range” and a CC adjustment as well as a voltage adjustment. In other words, these drivers will operate in CC mode as long as you are within the ‘voltage range’.
With my other CCCV supplies, you can set them to be in CC mode or CV mode. Since these boards dont use any resistors or zener diodes, etc, I would think they have to be operating in CC mode? I was under the impression that was the only safe way to run a direct driven LED to prevent thermal runaway.
Thats a lot of verbage to say I assumed these drivers would be operating in constant current mode?
That brings me to the second thing that has me confused about your numbers - the graph you posted above showing voltage vrs current for these LED’s. Looking at that graph, I dont see how you can get the currents you listed at the voltages you show. I have always understood that if you apply a given voltage to an LED it will draw a specific current. That relationship is shown in that graph you posted which I will post again to make it easy.
Looking at that graph, if you apply 3 volts to one of these LED’s, you should get a tad under 200 ma - or looking at it from the other direction, if the LED is drawing 200 ma, the voltage drop will be 3 volts.
At the 2.75 volt level, the amp draw drops to about 50 ma - or at 50 ma draw, the voltage drop will be 2.75 volts.
So, if that graph is correct, I get very different numbers from yours for min and max watts.
.05 x 2.75 = .1375 watts min
.2 x 3 = .6 watts max
In doing the same checks on my setup I get the following numbers. I ordered the 320 version which has a min max current range of 12v to 24v and current range of 6.67 to 13.34amps.
With 6 panels, my max amp draw is going to be 13.34 / 6 = 2.2 amps per board. With 12 parallel sets of led’s thats .185 amps/led. Looking at the graph again, that works out to roughly 2.98 volts or .55 watts per led x 98 led’s = 52.9 watts max per board x 6 boards = 317 watts total. Thats great because that driver is max 320 watts.
My minimum however is zero watts. If I turn down the voltage to 12 volts, that below the minimum voltage for the led’s, so they wont light up at all.
If I stick with the minimum amps in CC mode at 6.67amps / 6 boards = 1.11 amps per board or 1.11 / 12 = 93 ma per led. Looking at the graph again, when drawing 93 ma, they will be at roughly 2.83 volts, so my minimum ‘operating’ power will be roughly .93 x 2.83 x 98 = 25 watts per panel x 6 panels = 150 watts total.
Or… am I completely misunderstanding how this works?
By the way, does anyone know where to get the user guide for these drivers? All I can find is the basic PDF and an Instalation guide, neither of which gives any info on how to adjust them to operate in the range you want.
This is as close as I can find on the main PDF.
Hi there @Larry3215, seems to me that your math is correct. I was assuming that there was a dynamic relationship between Amps and Volts, however in the graph that is a static result no matter effective Amp or Volt.
I run my driver in CV mode. In the HLG series drivers Type A the the volts and current are controlled with a screw driver that will increase as you turn.
I have been very busy however I bring out the multimeter and see what is measured. My guess is your math is correct. Thanks for bring this to my attention.
Hi Roux, I sure wish I could find a user guide for these drivers. Im curious to see what you get when you do those measurements. Im going to have an in-line Wattmeter on my setup that will show the driver output volts and amps in real time. I’ll be sure to post my results as well.
That last image I posted “Driving Methods of LED module” is not really very clear to me. The wording is a poor translation at best and Im not clear on the “Constant Current region” they have circled on the graph. Its a confusing way to express this. Based on the specs for voltage and current ranges, I would have expected a different shape to that graph. I also would have expected the CC “region” to be the area under the curve rather than the knuckle where they show that bend in the curve.
Looking at the line where it says this:
In the constant current region, the highest voltage at the output of the driver
depends on the configuration of the end systems.
I am taking that to mean that the driver output voltage will be determined by the number of LED’s in series. In other words, if you have 8 LED’s in series, thats 3 x 8 = 24 volts. BUT - that voltage will be based on the current draw at the time.
As far as operating in Constant Voltage mode, I dont see how thats possible. LED’s dont survive constant voltage unless there is a way to limit current flow - resistors, zeners, CC power supply, etc. You must have something in the circuit that limits current flow or they go into runaway mode and die.
Did your driver come with instructions for setting the voltage/current - hopefully with some better details on how it works?
The “Installation Guide” is no better than this PDF and has zero to say about settings, adjustments, etc.
Here is how I “think” these drivers work based on my other experience with CCCV supplies…keep in mind I have never touched one of these specific drivers, and cant find any detailed instructions, so take this with a (very) large grain of salt
Since these are designed specifically to drive LED’s, I am assuming they must prioritize the CC mode when operating as long as you have the settings within the ranges listed in the specs. Again, because if they didnt, there would be instant runaway of the current and burned up LED’s if the current wasnt limited.
I think the voltage setting is going to work like an upper limit while the current setting has priority. In other words, you set the current to a certain value within the spec’ed range, and the driver will increase the voltage until that amount of current is flowing - up to the limit set by the voltage pot.
Thats going to work in reverse to some degree. If the voltage gets turned down to a voltage thats less than the total of the series voltage of the LED’s, then the current will drop to what ever level is dictated by the graph above that shows the voltage/current relationship. The current will still be limited and have priority over voltage changes.
In other words, if you set the voltage output to be say 3 volts/led, the current will go up to 2 amps per LED - IF - both total voltage and total current of all the LED’s on the board falls within the adjustment range of the driver.
At the same time, if you turn UP/DOWN down the voltage or the current settings, the total other one will increase/drop no matter what the setting is - all based on that graph showing the current vrs voltage of each LED.
Once things have settled, the current will be held constant - as long as both current and voltage fall within the adjustment range.
I hope that makes sense. I didnt express it very well.
Well, I was wrong about at least some of my thinking on how these drivers work.
Turns out you cant turn the strips off by lowering the voltage. The driver automatically keeps the voltage at the minimum level needed to light the led’s no matter how far you turn it down. In my case, thats 20.5 volts.
My minimum power level, with both pots turned down all the way, is 4.7 watts total = 20.5 volts x .23 amps.
Im maxing out at around 330 watts, but I havent let it stay there very long.
Im running a series of tests now and will report back later.
Oh - Im also a bone head and made two major mistakes. Luckily, neither broke anything.
Be careful when you insert the 18 ga wires into the strips and dont push them in TOO FAR. You will break the locking tabs off the connectors! Fortunately, the connectors still hold the wires in just fine and they are removable, but its more difficult.
I also did another major bonehead move and connected two of the strips with reverse polarity. They survived, but I dont recommend doing that either!
More notes and some pics later…
Oh - if I turn down the amp pot so the amp draw is below the rated minimum current level - 6.67 amps in my case, the strips flicker. That must be what they are talking about with the “hickup protection”.
Rather than cross post, Im going to put my test results in the main Solstrip thread.
Thank you so much for this great DIY project @Roux. I’d like to get away from the heat of my 216W of high output fluoros and 750W hps. I’m a do it myself kind of guy. I very much appreciate the model to follow. This is another of your projects to work into my budget, the other being your rosin vise.
Keep growing strong