[agoutihead]

Ok I know I want to go all LED for a variety of reasons.

I am just a little unsure of what the best layout is with exactly the amount of fixtures I would need looking for the best possible light spread, yet keeping the amount of actual draw watts as low as possible.

This is for a 32 plant grow, 4 rows of 8 split with a walkway down the middle 2.

I've come up with 2 different scenarios, what do you guys feel would be the best?

Scenario 1:

The following are specs on new LED fixtures that have come out this year that have reflectors (NOT optics) built in & according to the manufacture, increase yield because of a better output of 20% more.

96, 3w diodes per fixture x 14 fixtures = 1,344 total diodes
96 diodes x 3w = 288w per fixture x 14 fixtures = 4,032 rated watts
192w per unit of actual draw power x 14 fixtures = 2,688 actual power consumption draw

Scenario 2:

200, 3w diodes per fixture x 8 fixtures = 1,600 total diodes
200 diodes x 3w = 600w per fixture x 8 fixtures = 4,800 rated watts
342w per unit of actual draw power x 8 fixtures = 2,736 actual power consumption draw

The overall power consumption & price between the two options is negligible, so I'm not using those as determining factors. The 2nd option has more total LED's but if the reflectors are true to helping increase everything by 20%, then maybe it is working going with the new units?

Both units have an 8 spectrum lighting system that I can get the actual break down of in a day or two.

Which would you choose & why?

[agoutihead]

Shit I meant to post this in the lighting section... mods can you please move?

Thanks.

[rives]

I would go with option 1. Assuming that the LEDs run at the same power, you are going to be better off with more fixtures because of the footprint. As your drawing shows, each plant will receive light from both sides, where with Scenario 2, there will be a dead zone between pairs of plants. I think this is the biggest failing of the small, high wattage fixtures - the footprint suffers, and the "core" area can actually receive too much light.

For instance, I have a Lumigrow ES330, and had thought about getting a second one and up-sizing my tent. However, after doing several grows with it, it seems to me that I would be better off with (4) ES165's - same power, better and more even lighting.

[Terpene]

Originally Posted by rives

I would go with option 1. Assuming that the LEDs run at the same power, you are going to be better off with more fixtures because of the footprint.

^ This.

In my experience with LED, unless you run higher wattage fixtures, the lights will need to be nearly on top of the plants (within 10 or so inches from canopy) for 1200-1600 umol.

With the 500w+ 3w fixtures, you can run them about 15-18 inches over the canopy for better spread, but they're still very directional lighting sources, not nearly as spread as HPS.

I should note that if you run the higher wattage fixtures closer than 10 inches from the plants you WILL bleach leaves, dry out leaves, etc from UV output. Here are some examples...



No, that's not spider mite damage, that's UV damage from the LED! This plant was sitting 3 inches under the fixture to push the buds to perform better, but in reality we just learned that the leaves cook under that much light. Smoke was great though..



LED flowering brightness. I can get the same reading from this meter at noon outside in July. For comparison a 600w HPS will lay down 1100 at the canopy.

[agoutihead]

Ok so since there isn't much spread/flood of LED light & it is mostly directional & focused down, I think I am going to take option 1 and add 1 more light to each double row so every 2 plants will have their own light fixture, which are the 96 diode fixtures and 16 total fixtures instead of 14. (what the hell is a few hundred dollars at this point lol)

What kind of fixture were you running to produce that bud? It looks killer. And from that reading (over 2000?) compared to HPS levels it seems LEDs blow HPS out of the water when you have the proper fixture.

Also what is 1200-1600 umol and why & how should I be shooting for it?

[foomar]

With an older 60 deg model the useable light footprint is the same as the size of the fitting , would have to be almost touching for full coverage.

What room size is available and what are the dimensions of the lights ?

Helped a mate set up an led room last year and he ended up needing twice as many lights as he thought he would for the space , unless they have radically improved in a year this may still be the case.

[zachrockbadenof]

i'd luv to replace our 4 1000w hps/mh's with led's, but they are toooo bloody expensive...

[agoutihead]

Originally Posted by foomar

With an older 60 deg model the useable light footprint is the same as the size of the fitting , would have to be almost touching for full coverage.

What room size is available and what are the dimensions of the lights ?

Helped a mate set up an led room last year and he ended up needing twice as many lights as he thought he would for the space , unless they have radically improved in a year this may still be the case.

What type of units did your friend have, were they 1w diodes or 3w diodes?

How many diodes per fixture?

[foomar]

I experimented with the original 126 penetrator , mate used a better model off ebay and they had to be touching , no idea if 3 watt have enougth output and dispersion to allow spaceing between units.

After nearly a year he has got the yield back up by training and scrogging , 600 w sodium was replaced by 6 x 126 w which is about 600 w actual draw , so watt for watt in his case.

I think he should have waited for the current gen or better , hopefully the recent 3 w models have improved matters , but they had a long way to go

[agoutihead]

How can I get a MOD to move this to the lighting sub-forum?

I tried to PM one but I can't apparently...

Can anyone PM one for me with a link to this thread?

Thanks.