Am I overbuilding This Cob Light??

Sxott

Sxott

Well-Known Member
I'm having trouble finding a HLG-185H-C1400B for the cxb3590 build. Anybody know of any places that have them in stock now?
 
bizfactory

bizfactory

Well-Known Member
SupraSPL said:
863 vs 1200 PPFD, I think this explains the phenomenon of nute deficiencies when growing with COBs versus HPS, the plants are hungry and a hungry plant can show a wide variety of symptoms that can have growers chasing their tails. This is especially noticeable if you switch from a dim vegging area to a bright flowering area.
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That has me thinking...y plants have been vegging under 4 CXBs @ 1.4 A (+ PlatinumLED P300) and started showing calmag deficiency almost immediately. Should I just blast them with nutrients next time and see how they do?

Edit: Looks like the B version of the driver might be available here http://www.trcelectronics.com/View/Mean-Well/HLG-185H-C1400B.shtml
 
AquariusPanta

AquariusPanta

Well-Known Member
bizfactory said:
That has me thinking...y plants have been vegging under 4 CXBs @ 1.4 A (+ PlatinumLED P300) and started showing calmag deficiency almost immediately. Should I just blast them with nutrients next time and see how they do?

Edit: Looks like the B version of the driver might be available here http://www.trcelectronics.com/View/Mean-Well/HLG-185H-C1400B.shtml
Click to expand...
I believe I had a similar problem during my last grow around. Could have been due to the COBS, pH of tap water, the soil, or the strain itself.

Maybe don't blast them with nutrients but just add calmag to the typical veg shake. Maybe that's what you meant but would like to be precise with my advice.
 
bizfactory

bizfactory

Well-Known Member
Yeah makes sense. I went 1/4 strength last watering including calmag so I'll probably just up it to 1/2. They were also transplanted about a week ago so the FFOF should still have nutrients left as well. Thanks man, this is a good problem to have if it's caused by our lights!
 
bicit

bicit

Well-Known Member
SupraSPL said:
Those numbers were calculated from the SPD curves thanks to the hard work of @alesh and @MrFlux
View attachment 3394460

I have not included that data in the spreadsheets but it may be a good idea to add a umol/s/W column.
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I'm not sure I understand the scale of this sheet. It would appear based on this that high CRI, low kelvin light sources are more efficient than low CRI, high kelvin light sources according to this chart. Am I missing something?
 
alesh

alesh

Well-Known Member
bicit said:
I'm not sure I understand the scale of this sheet. It would appear based on this that high CRI, low kelvin light sources are more efficient than low CRI, high kelvin light sources according to this chart. Am I missing something?
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You have to realize that these values take in account SPDs only. They're about spectra, not the emitters themselves.
Multiply these values by each COB's efficiency for a more meaningful result.

And yes, had high-CRI warm whites have the same efficiency as low-CRI cool whites, they'd have been more efficient for our purpose. One has to realize that plants utilizes photons and that the watts isn't a unit that weighs all the photon the same. 1 watt of 675nm light actually produces 50% more photons than 1 watt of 450nm light. In other words, 60% 450nm LED produces same amount of photons as 40% 675nm LED at the same power. 450nm one would produce less heat though.

Using µmol/J (µmol/s/W is actually the same unit) makes more sense than efficiency (W/W or J/s/W if I may) so if possible, fellow RIU members, please use this.
 
U

Uzzi

Well-Known Member
Hmm it looks like I have ended up with 33.9 PAR W/ft2. If I add a 50k dimmer as suggested before, will it simply allow me to dim the amount of light given off or does it also reduce the amount of electricity used?
 
bizfactory

bizfactory

Well-Known Member
Uzzi said:
Hmm it looks like I have ended up with 33.9 PAR W/ft2. If I add a 50k dimmer as suggested before, will it simply allow me to dim the amount of light given off or does it also reduce the amount of electricity used?
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If you have a Mean Well HLG driver it actually reduces the power used. You normally would just use a 100K pot for 1 driver though, not 50.
 
U

Uzzi

Well-Known Member
bizfactory said:
If you have a Mean Well HLG driver it actually reduces the power used. You normally would just use a 100K pot for 1 driver though, not 50.
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Thanks! I obviously don't have any idea about these dimmers yet. Do you or anyone else know of a link or thread to get my head around them? I'm driving two CXB3590's with one HLG-120H-C1050 CB.
 
tightpockt

tightpockt

Well-Known Member
bizry said:
That has me thinking...y plants have been vegging under 4 CXBs @ 1.4 A (+ PlatinumLED P300) and started showing calmag deficiency almost immediately. Should I just blast them with nutrients next time and see how they do?

Edit: Looks like the B version of the driver might be available here http://www.trcelectronics.com/View/Mean-Well/HLG-185H-C1400B.shtml
Click to expand...
Same thing happened to me..immediate deficiencies. Making me question led for veg...maybe not, u, just annoyed at having to dial everytging back in. Its hurting my timeline and production. I guess sometimes you have to go backwards to go forward.
 
Sxott

Sxott

Well-Known Member
Same here. The first led I tried was mars 2 . The plants immediately drooped down and starting turning yellow within days. They were with a few 400 mj and same variables everywhere other than the light over them. Bounced right back after sticking them back under the mh. A few diff strains. Same thing kept happening. Sold em and that's what led me here because I need LEDs to work for me. I hope that don't happen with these cobs. Have lots invested now.
 
U

Uzzi

Well-Known Member
alesh

alesh

Well-Known Member
SupraSPL

SupraSPL

Well-Known Member
Sxott said:
Same here. The first led I tried was mars 2 . The plants immediately drooped down and starting turning yellow within days. They were with a few 400 mj and same variables everywhere other than the light over them. Bounced right back after sticking them back under the mh. A few diff strains. Same thing kept happening. Sold em and that's what led me here because I need LEDs to work for me. I hope that don't happen with these cobs. Have lots invested now.
Click to expand...
To add a data point, I have been vegging with LED for many years with no problems. I use recycled organic soil, super soil style so I can't speak about chem fert approach. If they get hungry I top dress with more soil or just pot them up but I never bother with PH or add calmag etc. The water is 150 ppm well water at 7.5 ph.
 
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