Page 1 of 3


PostPosted: Wed Dec 06, 2017 5:24 pm
by Prawn Connery
They seem to work OK. I'm limited on space at the moment, so have to make this attic grow work in a 4'x2 space. Schooled myself on LEDs and built this jigger out of a bunch of Samsung strips and a couple of 240W Mean Well drivers. Pulls up to 520 watts (Mean Wells can be overdriven) with 3000K light and about 187 lumens per watt, so should be the equivalent of a 600HPS vertical grow, as LED light is all downlight - not reflected.

I guess I'll find out in a couple of months. Strains are Sensi Star and Acid, all feminised. Lights were flipped at 24 days for the Acid and 17 days for the Sensi Star. I was a bit slow out of the gate with the Acid, which is why the Sensi Star caught up even though I popped the seeds a week later.

Here they all are at 1 week and 4 days of flower. So about a month from seed for the Acid and three weeks from seed for the Sensi Star. Considering I've been hand-feeding them in coco until a couple of days ago, I'm impressed with the LED performance. Once I get this thing dialled in, I reckon it will give the vertical HPS a run for its money.

Best thing about them is nice, even canopy light and heat distribution. Oh, and no more bulbs to buy nor degrade over time. Total cost for this lot was about US$300 including leds, drivers, aluminium frames and wiring. Quite a bit more than a basic 600w HPS but prices are coming down and LED efficiency is going up all the time, so I had to start somewhere. I reckon in a few years, these types of builds will be similar in price to HIDs.


PostPosted: Wed Dec 06, 2017 6:08 pm
by dill786
they look healthy and lush

what are drivers?

i have a sensi star growing right now a clone but the seeds were from paradise seeds, i am at day 33 of flower and its looking good

Re: LEDs

PostPosted: Wed Dec 06, 2017 6:40 pm
by Prawn Connery
Bit like ballasts. They supply/control the current and voltage. They're dimmable, so you can turn them up or down. I'm running these flowering LEDs at about 75% power at the moment. I run my veg light (below) at 65%. Running them at a lower output makes them more efficient with less heat generated. They also last longer (heat kills LEDs). But it's only a small increase in efficiency, so there comes a point where you're better off just running them at higher power to get the most out of them for flowering, while you can turn them down in veg to control growth or if you only have a few mother plants or clones to maintain.

Here they all are just over a week ago, before I moved them to the flowering tent. Sensi Star's a good old strain. There may be better these days, but it's hard to go wrong with it. There are a few different pheno types - a real leafy indica, a leafy hybrid and a lemon sativa - and yields vary greatly between the different phenos, but pretty much all are potent in their own way and never a waste of time to grow.

These are the first femmed Sensi Star seeds I've grown, so it will be interesting to see how they do. They are certainly growing fast and don't seem to be as nute sensitive as the old (original) seeds. I still have some of the original (non-femmed) seeds left, so I might make some F2s one day, as Luc only sells femmed versions these days.

Re: LEDs

PostPosted: Wed Dec 06, 2017 6:45 pm
by Prawn Connery
I should add that for the first time in a long time I started seeing nutrient deficiencies (mainly Calcium, which affects phosphorous uptake, and magnesium), as the plants are growing like bastards under the LEDs and I was too conservative with my nutrient regime. But better to slightly underfeed than overfeed when they're young.

Re: LEDs

PostPosted: Wed Dec 06, 2017 10:02 pm
by DD Ramone
They are looking gorgeous to me...Fat and Juicy!

Grow On!

Re: LEDs

PostPosted: Thu Dec 07, 2017 4:05 am
by MadMoonMan
But how well will they flower?

Re: LEDs

PostPosted: Thu Dec 07, 2017 1:20 pm
by Prawn Connery
That's the $64,000 question. I'm hoping I flipped them at the right time and they don't overgrow the tent.

Re: LEDs

PostPosted: Thu Dec 07, 2017 3:27 pm
by bentech
that frame holding the strips looks impeccable!

you must have a metal chopbox
or quite the hand with the hacksaw...

Re: LEDs

PostPosted: Thu Dec 07, 2017 4:28 pm
by Prawn Connery
Nah. I ordered everything to length (4x 600mm of 40x25x3mm U channel, plus 2x 460mm of 25x20x3mm L channel to hold the frame together) and drilled and screwed it all myself. I also did the wiring, of course.

The veg frame above is 4x 2' Samsung F Series strips in 5000K, which are double-row (144 diodes) and 48v/1.8a per strip. I wired them in parallel and hooked everything up to a Mean Well HLG-240H-48A driver. The A series drivers have adjustable voltage and current. Technically they are a constant voltage driver, but when operated at 48v or less, they act as a constant current driver. I have the veg frame dialed down to about 210w, or 65% of diode capacity.

The flowering frame is actually two frames, each very similar to the veg frame. This time I used 12x 2' Samsung H Series strips in 3000K, which are single row (48 diodes) and 23v/1.2a per strip. I mounted two of these strips per U channel (96 diodes total) and wired two in series and six in parallel hooked to exactly the same 240H-48A driver. Each flowering frame has the same number of diodes as the veg frame, but mounted over six instead of four U channels for better distribution.

The flowering frames are bolted together to form one 4' x 2' frame (actually 1170mm x 500mm), with one 240H-48A driver at either end for a total of 520w (overdriven).

All three (veg and 2 flowering) frames are 48v/7.2a capacity for a total of 345.6w, but as mentioned, I run the veg frame at 210w (65%) and the two flowering frames at 260w (overdriven) each, for 75% diode capacity.

Here are the flowering lights when I first set up the tent:

I wanted something flexible so that I could bolt together and pull apart each frame as required. I have plans to eventually go vertical LED, with one frame at either end of the tent, and four plants in the middle. That's not going to happen for a few grows yet. I'm just experimenting with the LEDs first to see how they do.

So far, I like them. :toker1:

Re: LEDs

PostPosted: Thu Dec 07, 2017 4:31 pm
by Prawn Connery
In case you're wondering, everything is drip-fed run-to-waste straight coco using organic-based hydro nutes. The reservoir has a bypass which sprays back into the tank to mix and aerate my nutrient solution every time the pump comes on (five times every 12-hour lights-on period).

Same pots and everything as my old vertical set-up that used to produce 1.3-1.4gpw.

Re: LEDs

PostPosted: Fri Dec 08, 2017 11:19 am
by nobodyknew
Been wondering about LED's myself - following this one with interest

Re: LEDs

PostPosted: Fri Dec 08, 2017 4:52 pm
by Prawn Connery
To answer a question from ben, those are two-gallon pots with straight coco, each being fed half to one litre of nutrient solution a day. That varies, of course, due to weather and stage of growth. When it's hot and the girls are in full bloom, they might drink up to 2 litres (half gallon) each a day.


PostPosted: Sat Dec 09, 2017 1:14 pm
by deran
Awesome show!
A big thx from the bottom of my heart!

RE the calcium
That's a known issue with LEDs, due to the missing wavelengths past the red PAR spectrum
Separately increasing Ca , with a cal-mag like product, the higher the ratio Ca:Mg, the better of course .. , pump it up by an EC of 0,3 , as your very first compound when mixing your solution, solves most strains, separately increasing temperature by 3-4 C , compared to hps ideal, helps too "adjusting" those issues, its simple, just juggle your knobs towards your wanted output



Re: LEDs

PostPosted: Sat Dec 09, 2017 9:44 pm
by Intrinsic
:popcorn: woohoo Plants and tech ... my favorite combo.

Re: LEDs

PostPosted: Sun Dec 10, 2017 2:54 pm
by Prawn Connery
MadMoonMan wrote:But how well will they flower?

Prawn Connery wrote:That's the $64,000 question. I'm hoping I flipped them at the right time and they don't overgrow the tent.

Damn you! :emp:

Two weeks and two days of 12/12 and they're still going mental.