Let's talk DIY lights


Hopefully you’re doing well in whatever career path you took anyway. I’ll try to snoop around cutters site for those specs. But new site doesn’t seem as user friendly as old one.


I know that the amount of red leds have been reduced to 33 from 99 bcause they said it was a bit of over kill and it would be slightly cheaper to run but still efficient on flowering.
He did a big light for another grower and reduced them to 15 per board still with great results.
I am sure it will be a great light but its alway good to have confirmation from another expert in the field, after all it is a significant investment for me. I eventually did a trade in the steel industry they call it a 1st class welder in Australia have contracted on most jobs mostly on coded jobs high pressure gas and oil pipe lines,decompression chambers, diving bells etc i had a work accident and broke my back resulting in a ruptured Aorta and blood transfusion, broke my back again since then, now they have taken my pain relief from me,which brings me here learning how to grow my own pain medicine.

Thanks again hope you can work out the site


Spent about 45 min and All I can find is nominal data.

Again you’ll be good running the whites as I stated, you just have a little more driver than you needed to buy. On the reds though, they’re usually like 2-2.5 volts. Which is a little lower than most. Having 33 diodes on red channel screams 3 parallel strings of 11 diodes in series. If that’s the case, that channel would be somewhere in the neighborhood of 24-36 volts.

Mark makes them, so he would certainly know better than I do. But if you have a third party working between you and him, just make sure you’re all on the same page with having the correct components. And make sure to post some pics too, that should be a very cool light.

Sorry to hear about your back too brother. Hopefully some good week gets you the relief you need.


This was there reply

I just had a look into the hlg-240h-c1400b data sheet and can in fact see that Voc (max open circiut) is 182V.
I had thought that was the CC range of the driver. (Have about 10 custom SolSkin builds going right now so I have gotten a bit muddled between builds, I do apologise). Although it would work, you could run into trouble with derating due to overloading, however minor it may be so I’m glad that has been picked up! I have been using CV drivers recently on these builds which is where I believe I have made the mistake.

My assumption from reading below is that the ‘3x3000K channels’ etc, referenced is meant to be 4? As there are 4 boards with 3 channels each? Please correct me if I am misunderstanding.

The HLG-185H-C1400B will not work in our application as it has a CC range of 71-143V, and if you are wanting to run the 4 boards in series, it adds to 180V per channel on each of the two white channels which is well over the range of that driver.

In this case, I can offer a HLG-320H-C1400B which has a CC range of 114-229v instead of the HLG-240H-C1400Bs quoted.
I would have to order this in and cannot guarantee you will receive it by Christmas at this point. (I will try my very best to make it happen should you wish to go down that path).

Yes, the forward voltage and max current on the red channel is different as there is a different amount of LEDs, they are on a separate circuit, and the red LEDs are inherently different to the Nichia V3.

In this instance, if we are running 4 boards of reds, and running with a CC driver @ 1400mA, forward voltage will be at 24V ea. Board.

We can use the ELG-75-C1400B (range of 27-54V) by running 2 lots of 2 boards in series, then running those in parallel together. This will give us 48V @ 700mA per 2 boards on the red channel.


I thought you said 3 boards?


its 4 boards its on the list of components

thanks again


That’s where I screwed up, sorry. Makes sense then. I now understand more reds too, that’s two channels in parallel and two in series on the elg-75. I’m not a huge fan of that, but it will work.


What would you suggest is the best way, as they have not packed it yet, just want the best config and light, and i will for sure send you photos

thanks mate this is doing my head in


Lots of ways you can do it, will depend more on what he stocks. The elg-75-700 is same driver with half the current and twice the voltage. That would allow a straight series connection. Meanwell probably makes half dozen drivers that could be made to fit there. I usually use hlg series because of the low line voltage derating on the elg. There’s a few of the hlg’s that would work too.


This is the list of components he will get in what he does not have

4 SSK-3N-3K-4K-660x SolSkin 3CH Nichia 3/4/660x33
2 HLG-240H-C1400B Meanwell 250w 1400mA Driver
1 ELG-75-C1400B Meanwell 75w LED Driver
3 1-10 Dimmer Dimmer 1-10 suits Clip/HPM WP
1 Cutter-TIMDSA-100- Thermal Tape 100mm wide $
20 Wire-18AWG-Black- Hook up Wire 18AWG Black
6 221-412 Con Terminal Block 2 way
3 221-413 Con Term Block 3 way
48 M3 6mm Pan Head Screws for Mau5 Kit
48 Misc Part m3 nyloc nut
8 Misc Part grommet rubber


really sorry to take up so much of your time @dbrn32


No worries. I would be guessing at what you need for hardware. The wagos will come in handy for sure though.

The only thing I really don’t see that you will need is a power cord or cords. If each driver is going to have its own cord you’ll need 3. And I’m not sure if Mark has them, but there are some really cool waterproof cable joiners available for around $5 US.


They told me its just the one power cord to the wall


Ok Mark at cutters rang and said solskin boards have multiple built in resistors to prevent any thermal runaway, and they are built specifically to prevent this problem, he said if you look very closely at the solskin boards you will see small black specs which are the resistors,


That’s fine as long as that’s what you want. Also, those resistors balance the voltage from string to string within the board. Provided resistors don’t burn out, the different sections of the board should indeed be be protected. However I don’t think the resistors do anything to protect the boards from taking all available current from driver should you loose a portion of the circuit.

You can certainly wire it in parallel if you want, lots of people do. Lots of the big lighting manufacturers do because it allows them to meet certifications easier with the lower voltage. The only downfall to wiring in series is the high output voltage on driver. But that’s pretty simple to combat, you just make sure your wiring job is solid and don’t mess with it while it’s energized. What you gain is usually a much easier to wire light with less connections to worry about. And if any of your connections do fail, that portion of the light just doesn’t work.

I would draw out on a piece of paper 4 boards with 3 channels each wired each way and take a look for yourself. You have a solid driver application to wire them in series, so I’m not sure why you would purposely go out of your way to do anything else.


@dbrn32 are these drivers any use for me as I have access to about 20 for free?


Sure! I can think of a few options for them, take all you can get for free.


Dbrn32 two things 1. Thanks for all your help on my lights I have built. Would not have the room I have without you. 2ns is a question on a 4x8 if I went with qb120 or qb132 how many would I need if i was driving them at 700ma? I’m back and forth everytime I look at this. Strips one day qb. Lol. Harvesting Sunday makes my mind wander.


The voltage on boards is a little different, so is the output. Qb 120 is 24v at 700ma is like a 14-15 watt board at something like 2.9 umol/joule. Qb 132 is 36v board at 700ma is like at 23 watt board at probably about 2.85 umol/joule.

Qb 120 figure about 41 umols per second per board
Qb 132 figure about 65 umols per second per board

Then estimate a 4x4 to 1.49 square meters and multiply by desired ppfd. Once you have a total light output, divide by each amount to find number of boards required.

For example…1.49*800 (desired ppfd) =1192 umols per second. 1192/65=18 132 boards. 1192/41=29 120 boards.

You couldn’t possibly fit either I don’t think. So would require you to run lower ppfd or raise current.


What do I raise the current to? It’s for flower so I thought why not snag some of the qb132 $100 for 4. What configuration makes the most sense? Is it possible to use 8 if driven to max?