My Plan For A Cree Cxb3590 Light Bar

[Toaster79]

i don't have any reflectors

Sorry it was a mix up

Raise your lights obviously. Happened to me to at 4" under 75W 3070

 

[Toaster79]

i'll send pics later, about 36" off the canopy, i had the same problem you did thought they need food but they were burning! and burning at all the new growth spots, older leaves not so bad.

absolute worse time to burn them is weeks 1-3 of flowering, it will destroy your harvest. at this point i don't turn lights to 100% until week 4, any thoughts?

What are your temps and humidity at the top of the canopy?

 

[5ecret 5quirrel]

What are your temps and humidity at the top of the canopy?

22C @ 70Rh week 2
here's my bar build cree cobs
https://www.thcfarmer.com/community/threads/noob-builds-cxb3590-3500k.78030/
yeah i have a low room not much space to raise it, i'll think of something. lights are on the ceiling definately not 4 ft off the canopy. thanks brother this is helpful

 

[Toaster79]

22C @ 70Rh week 2
here's my bar build cree cobs
https://www.thcfarmer.com/community/threads/noob-builds-cxb3590-3500k.78030/
yeah i have a low room not much space to raise it, i'll think of something. lights are on the ceiling definately not 4 ft off the canopy. thanks brother this is helpful

So about 600W 36" away. I cant imagine how could you burn your plants. Whats the footprint of your room?

 

[testiclees]

A little ways back a couple gardeners were asking about uvb. There is a new tube on the market that is far more powerful in providing uvb. Its a t5 made by agromax. I have one but i havent tried it out yet.

I burn about 600w of cxb and v29 in a 24x50. I will crisp early flowering plant leaves at distances <24. But irradiance issues at 36" without lenses or reflectors is curious.

 

[5ecret 5quirrel]

So about 600W 36" away. I cant imagine how could you burn your plants. Whats the footprint of your room?

 

[Toaster79]

I can't see any light burn there

 

[5ecret 5quirrel]

I can't see any light burn there

you're right, it's barely visible, it's the second time it's happened so i caught it earlier. the new growth was yellowing, and a calmag def, everything is cool ph is cool, plants were 80 cm from the light now it's at 100 cm off the canopy. thanks for all the feed back brodda.

 

[SmokinJo421]

I bought enough to make two bars. Mouser.com came to about $590 including the $15 shipping. A pair of heatsinks delivered to Seattle was $135. Kapton tape was $13 from amazon. The power cords were about $12 each. So this will cost me $380 per bar not including the $41 cost of getting a supply of 300V rated 18ga hookup wire (300V because I wanted to have it on hand).

Each bar will be installed in a 2x3ft alcove and driven at 1050mA for about 150W per bar. The internal pot can reduce the current by half and Supra recommends running things mellow so we'll see.

Copied from RUI, I think:
"Same recommendations as far as drive currents

CXA3070 3K AB at 1.4A (52W) 43.3% $1.77/PAR W (aliex)
CXB3070 3K AB at 1.4A (50W) 45.4% $2.03/PAR W (digikey)
CXB3590 3K CB at 0.7A (49W) 51.7% $2.38/PAR W (digikey) (dang! :joint:)

You could run 4 CXB3070s at 1.4A on the HLG-185H-C1400 or
you could run 4 CXB3590s at 0.7A on the HLG-185H-C700

perfect match for our favorite drivers :leaf: makes you wonder if Cree is watching
Last edited: Feb 21, 2015
SupraSPL, Feb 21, 2015

So for the money you spent & incorporate building & all that. Do you feel that it was cheaper to build the light vs purchasing 1?
I've recently looked at that sameconcept and it seems it's not much of a difference