DIY leds Discussion Thread for all your how tos and doubts and anything related

[Aristoned]

Recovery ventilators technically can work either way, vice versa. If you had a small portable AC unit for the tent, you could keep the air inside cool, but also be ventilating it almost full blast at the same time, without sealing it and needing to supplement c02. Keep the rest of the room warmer instead of inside the tent.

I don’t want to do that.

I just went through the end of winter trying to keep the whole place warm, it is far too expensive to it that way. I’ve decided to heat the plants directly instead.

Last night I was keeping temps around 75° F and 1.5 kPa VPD, then when lights go out I keep it around 68° F. I’ve spent the past several weeks playing with configurations to dial it in, I’ve been able to hold steady temperatures from 88°-75° so far. This should give me the spread I need for rapid vegetative growth and finish with a heavy, stinky, sticky yield.

One of the biggest things I’ve learned about is plant metabolism by adding heat and taking it away.

 

[Drop That Sound]

I gotta question for you guys.. if you had both variable constant current and voltage controls.. using properly rated DC-DC buck/boosts converters for circuits with LEDs (and or low voltage incandescent bulbs!), which knob you you be using just to dim them most the time, and which one would not get used as much?
I'm replacing the small trimmer pots with larger single and multi turn pots, for better remote control of the modules. Would you turn down the voltage or the current, or does it depend on how finicky the led modules are whether you use one over the other for dimming?.


I'm also wondering if its a good idea to have so many potentiometers on the extra control panel box I made. I don't wanna be able to bump one knob and throw the setting off if all I need is the other single dial for dimming..

The crazy part is I have multiple rails coming from my PSU, so I'll have 3 seperate buck/boost modules that each have CC and CV control. I left one rail fixed, for plugging in accessories just like a PC, with the molex connectors still attached.

 

[Aristoned]

I gotta question for you guys.. if you had both variable constant current and voltage controls.. using properly rated DC-DC buck/boosts converters for circuits with LEDs (and or low voltage incandescent bulbs!), which knob you you be using just to dim them most the time, and which one would not get used as much?
I'm replacing the small trimmer pots with larger single and multi turn pots, for better remote control of the modules. Would you turn down the voltage or the current, or does it depend on how finicky the led modules are whether you use one over the other for dimming?.


I'm also wondering if its a good idea to have so many potentiometers on the extra control panel box I made. I don't wanna be able to bump one knob and throw the setting off if all I need is the other single dial for dimming..

The crazy part is I have multiple rails coming from my PSU, so I'll have 3 seperate buck/boost modules that each have CC and CV control. I left one rail fixed, for plugging in accessories just like a PC, with the molex connectors still attached.

Current.

I use XLG drivers for constant wattage. The amperage is controlled by a 50/50 pot for 330° sweep of 50% power, giving me extreme resolution. The driver will adjust voltage to compensate to a point. Each setup is calculated to work within the “power island” of the driver.

Incandescent, I would simply trim the voltage.

 

[Drop That Sound]

Another thing.. 2 of the buck/boost converter modules I got (20a 300w) weren't exactly the ones advertised on the pictures from the seller. They were supposed to have 2x 3296 w104 100k trimmer pots, which I was expecting for the CV and CV controls, like every picture on the net shows on all the other brands of the same model.

They're exactly the same looking module and circuits as far as I can tell, but instead have a 50k (for the current) and a 100k for voltage control. That's the only difference, and I'm not even sure why they went down to a 50k when all the others have the 2 100ks.. Hmm.

I had bought a pack of 100k linear single turn pots expecting to use them all up, but now I gotta wait a week to get a couple 50ks.. unless, I can just use a 100k in place of the 50k instead with no problems, like all the other brands are using?

So, I also looked up how to turn a 100k pot into a 50k, by jumping a 100k resistor to 2 of the outer pins of the pot, but then it will cause it to be more of a curved response than a perfect linear taper when trimming. According too some (mostly guitar\audio enthusiasts), its not that big of a deal, and the chart I seen comparing a 50 k with a modded 100k the lines are barely off.

Dangit.. I should probably just wait for the 50ks so they match the parts I'm swapping for, even though it seems like they are the ones using the wrong part to begin with..

 

[Drop That Sound]

I like the idea of using even more pots in series to dial it in better with finer adjustments, but then Id'd have way to many knobs, lol. Is that what you mean by the 50/50 pot?

FFS, my grow lights control panel is gonna look like this if I don't stop getting to sophisticated with it..

 

[Drop That Sound]

^ Thats the modules I'm using. Mine came with a 50k for CC and 100k for the CV instead of matching 100k pots.

 

[Aristoned]

^ Thats the modules I'm using. Mine came with a 50k for CC and 100k for the CV instead of matching 100k pots.

Look for a resistor on one of the wires to the 50k pot.

 

[Drop That Sound]

So the 2 SMD resistors (R10 and R9) connected directly to the 50k CC potmeter on the circuit board are a 01b (1kohm), and the other one that's farther away is a 135.

 

[Aristoned]

So the 2 SMD resistors (R10 and R9) connected directly to the 50k CC potmeter on the circuit board are a 01b (1kohm), and the other one that's farther away is a 135.

That must be a maximum current limiter.

I’m using a resistor to provide a minimum current, if I took that out I could only achieve 50% power maximum unless I unplugged the pot.

 

[Drop That Sound]

Anyway yeah mine are a bit different than the 2 versions in the videos.. Who knows, maybe they're better, or worse? Maybe having a 50k for the variable current control is better anyway. I'll just order some 50k pots and wait to add them later, and keep the smaller trimmer pots attached for now, and maybe try using a 100k like all the other modules have..

I might even go with linear sliders instead of turn dial pots.

 

[Drop That Sound]

I kinda like that idea BTW, having a full on analog mixer style control board. With I dunno.. like 30 channels, one for each of the specific wavelengths of possible LED diodes? With fine and coarse CC/CV adjustments on each channel if needed. So you can mix up whatever perfect blended spectrums you want, just like a music producer mixing and mastering tracks, but for grow lighting instead.

I know... They got digital micro controlled LED grow light setups like that now, that you can alter the spectrums, probably even with touch screen controls, or wirelessly through an app, etc.... Probably limited to a few select fixed settings though..

I can mod my dc-dc converters and add digi controls like in the above videos too, but I want that nostalgic old school analog hardware feeling when I tune my lights. With knobs and faders. No wait, I want both!

 

[Aristoned]

View attachment 19190340 View attachment 19190341
Anyway yeah mine are a bit different than the 2 versions in the videos.. Who knows, maybe they're better, or worse? Maybe having a 50k for the variable current control is better anyway. I'll just order some 50k pots and wait to add them later, and keep the smaller trimmer pots attached for now, and maybe try using a 100k like all the other modules have..

I might even go with linear sliders instead of turn dial pots.
View attachment 19190342

Those two modules are definitely not the same, I’m seeing a small wire going from one of the resistors to the capacitor. That must mean this board isn’t exactly meant to do what it is doing. That must be why they have a set minimum and a set maximum.

That unit must melt down if you go to zero or 100%, kinda like electric cars.



Customizing a spectrum to the point of changing individual frequencies may not be as beneficial as you’d think. I drenched the Kush in blue light and she hated it, now I’m pouring infrared all over her and she’s loving it.

The leaves are only burning where there isn’t any resin. Perhaps too much IR for flower?

 

[Aristoned]

I kinda like that idea BTW, having a full on analog mixer style control board. With I dunno.. like 30 channels, one for each of the specific wavelengths of possible LED diodes? With fine and coarse CC/CV adjustments on each channel if needed. So you can mix up whatever perfect blended spectrums you want, just like a music producer mixing and mastering tracks, but for grow lighting instead.

I know... They got digital micro controlled LED grow light setups like that now, that you can alter the spectrums, probably even with touch screen controls, or wirelessly through an app, etc.... Probably limited to a few select fixed settings though..

I can mod my dc-dc converters and add digi controls like in the above videos too, but I want that nostalgic old school analog hardware feeling when I tune my lights. With knobs and faders. No wait, I want both!

My approach is finding a good base spectrum and then supplement from there. This way each diode is producing the same frequencies of light across the entire canopy, then I can mix any IR I need as a “thermal blanket” for the plant. That’s how I achieve 88° F inside the tent and 72° F outside the tent.

Everything I’m reading tells me UV is not welcomed by cannabis, however, cannabis seems to love IR all the way into week four of flower. The resin production is absolutely fantastic, the smell is very strong and if you touch a bud your hand will be sticky for a couple of days.

 

[Neferhotep]

I might even go with linear sliders

How about a board with resistance wire and crocodile clip pick-ups?
You can easily fit ten or twenty neatly next to each other.
And one analog current meter per channel.

 

[Drop That Sound]

Those two modules are definitely not the same, I’m seeing a small wire going from one of the resistors to the capacitor. That must mean this board isn’t exactly meant to do what it is doing. That must be why they have a set minimum and a set maximum.

That unit must melt down if you go to zero or 100%, kinda like electric cars.

These 20a 300w DC-DC modules are pretty popular. People are reliably using them for everything including higher wattage solar installations, benchtop supplies, LED lighting, etc. They're CE, UL, and FCC certified, and have built in circuit protections. Yeah, it might be hit or miss on the quality a bit, depending on the seller. Some with knockoff chips missing the part numbers, etc.

I'll definitely be de-soldering the capacitors out of the way temporarily, just so I can unscrew the heatsinks and apply the thermal compound they typically forget to use on cheap modules for some reason...
I'll have dual 40mm fans actively cooling my converter/control panel box with all the modules, and barely pushing much current out of them. Never really exceeding or boosting past the input voltage, so should be as effecient as possible. I'll be maxing out at half of what they are rated for at the most, only on one of my 12v rails..

You're only supposed to need a fan at the full 15-20a output, and keep it under 65c. I'm actively cooling them anyway, even though I probably don't need to.

 

[Aristoned]

These 20a 300w DC-DC modules are pretty popular. People are reliably using them for everything including higher wattage solar installations, benchtop supplies, LED lighting, etc. They're CE, UL, and FCC certified, and have built in circuit protections. Yeah, it might be hit or miss on the quality a bit, depending on the seller. Some with knockoff chips missing the part numbers, etc.

I'll definitely be de-soldering the capacitors out of the way temporarily, just so I can unscrew the heatsinks and apply the thermal compound they typically forget to use on cheap modules for some reason...
I'll have dual 40mm fans actively cooling my converter/control panel box with all the modules, and barely pushing much current out of them. Never really exceeding or boosting past the input voltage, so should be as effecient as possible. I'll be maxing out at half of what they are rated for at the most, only on one of my 12v rails..

You're only supposed to need a fan at the full 15-20a output, and keep it under 65c. I'm actively cooling them anyway, even though I probably don't need to.

What I was thinking is someone came up with the design and others decided to copy the design. Sometimes they will miss a trace or two and compensate with a wire across the top or bottom of the board. The internals may be “bargain” instead of quality, or they went way too big and needed to limit the out-put current. Voltage is easier to increase than amperage, amps make heat and a lot of it.

I can take one amp, push it too 600kV and send that power across the country. On the other hand, if I had 600A with only 1kV I’d probably just start a fire.

 

[jonesfam7715]

These 20a 300w DC-DC modules are pretty popular. People are reliably using them for everything including higher wattage solar installations, benchtop supplies, LED lighting, etc. They're CE, UL, and FCC certified, and have built in circuit protections. Yeah, it might be hit or miss on the quality a bit, depending on the seller. Some with knockoff chips missing the part numbers, etc.

I'll definitely be de-soldering the capacitors out of the way temporarily, just so I can unscrew the heatsinks and apply the thermal compound they typically forget to use on cheap modules for some reason...
I'll have dual 40mm fans actively cooling my converter/control panel box with all the modules, and barely pushing much current out of them. Never really exceeding or boosting past the input voltage, so should be as effecient as possible. I'll be maxing out at half of what they are rated for at the most, only on one of my 12v rails..

You're only supposed to need a fan at the full 15-20a output, and keep it under 65c. I'm actively cooling them anyway, even though I probably don't need to.

How much efficiency loss?

 

[Drop That Sound]

How much efficiency loss?

300W 20A DC Buck Module Constant Current Adjustable Step-Down Converter Voltage

Output Current: 20A(max.), 15A (suggested)

Output Voltage: 1.2V to 36V DC

Efficiency: 95% (24V to 12V, 20A)

With a wide input voltage range from 6V to 40V (10V to 40V is suggested), the step-down converter can accurately adjust output voltage and current

Output Ripple: Less than equal 50mV

Wiring Method: Terminal

Short Circuit Protection: Self-recovery (cannot short circuit for long time)

VO+: Output positive

VO-: Output negative

+IN: Input positive

-IN: Input negative

CV: Output voltage adjustment

CC: Output current adjustment

EN: Enable, low voltage level shut off output; suspension, high voltage level is effective

When input and output is common grounded, no-load CV output constant voltage, CC output constant current

Working Tempreture: -10Celsius -75 Celsius

Designed with 75V/80A large current dual MOS tube

The buck module has 2 heat sink that could enhance heat dissipation

Wiring is convenient with these large current 30A screw terminals

Input and output use high frequency low resistance electrolytic capacitor, low ripple, stable output

Stable and reliable

Fine workmanship and durable

Widely used in industrial Automation, scientific Research Equipment, LED Lighting, air Purification, civil equipment,
solar panel voltage regulator, battery charging，wind turbines and so on

 

[Drop That Sound]

I'm ordering a couple of the smaller 150w 8-10a DC-DC buck/boost modules too, that will accept the lower 5v input from the same ATX PSU I'm using.

I'll need 2 of them to split the load from the 5v 20a rail, unfortunately.. I can't find any single 15-20a buck/boost combo modules that accept lower voltages like 3.3 and 5v. Just 6v and up, unless I go with a buck or boost only specific module..

Not sure if the bigger 20a 300w modules will even work with 5v input yet (might try later), but that would be nice if they did, so I could use one single bigger unit like I am on each of the 12v rails.

I'm cool with having a bunch of modules stuffed into an air cooled box anyway, and will have upwards of 5-6 different variable low voltage CC/CV controlled channels for all the different kinds of LEDs/bulbs on my newest rig.

 

[Neferhotep]

What's the combined efficiency - computer PSU and buck boost converter?