Bueno Time
Well-Known Member
Looking great MrFlux! Driver board looks nice and clean with those few meanwells on there. Awesome.
Step into my grow room
- Thread starter MrFlux
- Start date
Greengenes707
Well-Known Member
That's awsome, the grow and driver setup. I was just looking at one of the hlg240's to run 4 cxa's parallel last week. 150-180w running power total.
Is there anything special you do/add extra to yours when running parallel?
Is there anything special you do/add extra to yours when running parallel?
MrFlux
Well-Known Member
Parallel driving is not the recommended way because the results are unpredictable; It's a bit of a lottery of what Vf (forward voltage) your COBs have and hence how the current will be distributed among the COBs. The best thing (apart from not doing it) is to do you own "binning". For example if you had 8 COBs you could select 4 that are close together. Perhaps you could group the 4 lowest and the 4 highest and build two lights.
For the Vero 10 I see a spread of about 5% between highest and lowest Vf, and this has a significant impact on the current. Perhaps someone with CXA's can measure this for the CXA?
Chronikool
Well-Known Member
Hahaha...'fooling' people with your 'easy' and 'simple' setup...i thought series setup was hard enough...i did miss plenty of classes though.. 
Complimentz to your grow, knowledge and sharing abilities 'Fluxie...
Complimentz to your grow, knowledge and sharing abilities 'Fluxie...
MrFlux
Well-Known Member
It's kept kitchen clean inside so that I can the eat the leaves without worry
The nutrients they get is Plagron Alga Grow/Bloom, supposedly based on algae extract.
CaliWorthington
Well-Known Member
Those are some fancy Euro nutes, I don't think anyone is importing them into the U.S. I did find some on ebay, but they ship from the UK. Looks like good stuff!
Greengenes707
Well-Known Member
Thanks for the help. Supra alluded to that problem when I asked him.
Is there a way to use a resistor or something to regulate each string(cob in my case) to it's own needs(different Vf's)? ...in an efficient way of course. It would just be so nice to run them all on one driver.
spazatak
Well-Known Member
THIS ˆˆˆˆ
overthinkingismything
Member
Do you have a link handy for the silicone glue? The ideal holders aren't in stock and the COBs are too thin for the TE holders without compression springs.
Thanks!
EDIT: Found it! http://rollitup.org/t/cree-cxa-analysis.743645/page-6#post-9905498
EDIT2: Do you think a ceramic COB could be removed using this adhesive should the holders come back in stock? I was going to use a mix of artic alumina and artic alumina expoxy to create a weaker bond, but I fear that I would still end up destroying the COBs trying to remove them at some point in the future.
For the Kafuter I see "high adhesive strength, shear strength 18 kg / cm , the peel strength 6 kg / cm".
So about 47.5 lbs of force require to remove the COB. Hmmmm...
Thanks!
EDIT: Found it! http://rollitup.org/t/cree-cxa-analysis.743645/page-6#post-9905498
EDIT2: Do you think a ceramic COB could be removed using this adhesive should the holders come back in stock? I was going to use a mix of artic alumina and artic alumina expoxy to create a weaker bond, but I fear that I would still end up destroying the COBs trying to remove them at some point in the future.
For the Kafuter I see "high adhesive strength, shear strength 18 kg / cm , the peel strength 6 kg / cm".
So about 47.5 lbs of force require to remove the COB. Hmmmm...
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MrFlux
Well-Known Member
It's the most common bio feed around here. It gives me nitrogen toxicity when using the recommended dose so I use half that dose. Not sure if my plants are getting optimum phosphor levels now.
A resistor would work but gives a loss of ΔV * I, typically a few percent. You could replace the resistor with something that does useful work, like a single LED. Perhaps some combinations of red (Vf ~ 2V) and blue or white (Vf ~ 3V). Doesn't make it simple though
You can use one driver in series but it has to be high voltage then like 160V for four COBs. Positivity does this.
Yes that Kafuter stuff is too strong to be removed. I have tried regular non-thermal silicone glue ("Bison Power") and that can be removed.
CaliWorthington
Well-Known Member
Sounds like they need to tweak their formula a bit. Good thing you spotted that. I tried varying the amount of A or B in a 2-part formula, but I think it ended up causing slight phosphorus deficiency, so I stopped after a few days. I should add, that's just for one sensitive plant I've got. Most other strains don't seem to care what I do to the mix.
The most common Euro nutes here are Canna and House & Garden. I've found both of those to be pretty excellent.
MrFlux
Well-Known Member
Over the past weeks all plants except one were harvested.
Here is the ICE
Remember this little Cindy?
The cup is 300ml, not 250ml like I said earlier. The little plant is extremely top heavy but has alway kept perfect balance. This experiment has got me thinking to try a higher density of smaller plants:
This "Lake of Green" are 5 Cindy clones in a 60cm balcony trough. The object is to increase yield (while maintaining quality) and to simplify plant management (no more repotting or training).
It's never boring in the veg room
Flower room (wide angle so objects appear smaller). The light is hanging at an angle again
On the left two Blue Dreams (day 1F). On the right: ICE in front, Cindy in the rear.
Lemon Kush on the right; This grand old lady has lost all sense of decorum and lets it all hang loose
Here is the ICE
Remember this little Cindy?
The cup is 300ml, not 250ml like I said earlier. The little plant is extremely top heavy but has alway kept perfect balance. This experiment has got me thinking to try a higher density of smaller plants:
This "Lake of Green" are 5 Cindy clones in a 60cm balcony trough. The object is to increase yield (while maintaining quality) and to simplify plant management (no more repotting or training).
It's never boring in the veg room
Flower room (wide angle so objects appear smaller). The light is hanging at an angle again
On the left two Blue Dreams (day 1F). On the right: ICE in front, Cindy in the rear.
Lemon Kush on the right; This grand old lady has lost all sense of decorum and lets it all hang loose
Chronikool
Well-Known Member
Top knotch haul on the Ice...got it sorted....and all that from a DIY rig.....? and here i thought commercial LED panel manufacturers knew best...
God i hope that wasnt 12/12 from seed....i will never enter the comp again...
churchhaze
Well-Known Member
Yes, but it will take a few extra components.
1) You will need to turn current limiting off on the drivers you're using now, or limit it to the sum of the strings max current. (4 strings at 1A = 4A limiting)
2) setup a current mirror using nmos transistors (for sinking) or pmos (for sourcing). The fets in this configuration will mirror a reference current by raising/lowering their Vds (voltage across drain-source). Vds will get high to compensate for Vf droop, and keep current constant..
Check out my power supply design thread (jump to post #13)
https://www.rollitup.org/t/diy-cheapo-regulatorless-power-supply.831195/
It shows simulations of how the current regulation works. It's regulated now, and if anyone is interested, I'll add my latest (more complete) version.
It uses n channel mosfets to sink current, so even with high voltage strings, it's not dangerous to touch the sinking mosfet leads.
The most efficient way to use current limitation is to set the current limit slightly above what it would be without limitation. When the mosfets are limiting, they use WAY more power. When the limit is set higher than current would normally be, the limiting mosfets will remain "on", with minimal voltage drop across them. "On" is the most efficient mode for them to be in.
1) You will need to turn current limiting off on the drivers you're using now, or limit it to the sum of the strings max current. (4 strings at 1A = 4A limiting)
2) setup a current mirror using nmos transistors (for sinking) or pmos (for sourcing). The fets in this configuration will mirror a reference current by raising/lowering their Vds (voltage across drain-source). Vds will get high to compensate for Vf droop, and keep current constant..
Check out my power supply design thread (jump to post #13)
https://www.rollitup.org/t/diy-cheapo-regulatorless-power-supply.831195/
It shows simulations of how the current regulation works. It's regulated now, and if anyone is interested, I'll add my latest (more complete) version.
It uses n channel mosfets to sink current, so even with high voltage strings, it's not dangerous to touch the sinking mosfet leads.
The most efficient way to use current limitation is to set the current limit slightly above what it would be without limitation. When the mosfets are limiting, they use WAY more power. When the limit is set higher than current would normally be, the limiting mosfets will remain "on", with minimal voltage drop across them. "On" is the most efficient mode for them to be in.
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speedyganga
Well-Known Member
Hi mrFlux,
Really great grow. Thank you for charing.
This forum is amazing, each time new genius ideas and setup using different led and all of them output more than the g/W...
I was looking for the same dissipation method but unfortunately, 30x30 T profile are not available were I live. Do you think this one could dissipate the heat of 7 vero10 ?
cheers
Really great grow. Thank you for charing.
This forum is amazing, each time new genius ideas and setup using different led and all of them output more than the g/W...
I was looking for the same dissipation method but unfortunately, 30x30 T profile are not available were I live. Do you think this one could dissipate the heat of 7 vero10 ?
cheers
MrFlux
Well-Known Member
7 vero10's at 350mA on this heatsink would be pas de problème. A bit of airflow is recommended.
speedyganga
Well-Known Member
I like your pas de problème, I am myself from this country. 
I hesitate a lot, espec' because of your warning about the high voltage circuit. I electrise myself few month ago on the 220V wiring a hps ballast and went to hospital. (my bro put the whole house on while I shut it down, he didn't know I was wiring the ballast for the cab...)
Nothing too bad and I will continue playing with electricity but still I know how does it fill to have your heart doing strange stuff.
Now, I could for the same price either go for 14 vero 10 on a meanwell HGL- which is 400V and 500mA or I could use 6 vero 18 on a HG- giving 1050mA and 190V. 190V is obviously safer but can still be lethal isn't it?
The cooling of the vero18 will be more expensive I think as it involve big heatsink or watercooling/ ventirads. (at least 80euros). The cooling of the vero 10 would cost me two dissipator like the one you saw (35euros max). I would put my exhaust next to the dissipator and my fan recirculating the air should do the job for lowering the Tj.
But Is their a way to keep this safe ? I mean isolating with a resin the connection, linking the heatsink to the ground etc... I don't really know how can I get this really safe.
Sorry to hijack your journal mon ami
I hesitate a lot, espec' because of your warning about the high voltage circuit. I electrise myself few month ago on the 220V wiring a hps ballast and went to hospital. (my bro put the whole house on while I shut it down, he didn't know I was wiring the ballast for the cab...)
Nothing too bad and I will continue playing with electricity but still I know how does it fill to have your heart doing strange stuff.
Now, I could for the same price either go for 14 vero 10 on a meanwell HGL- which is 400V and 500mA or I could use 6 vero 18 on a HG- giving 1050mA and 190V. 190V is obviously safer but can still be lethal isn't it?
The cooling of the vero18 will be more expensive I think as it involve big heatsink or watercooling/ ventirads. (at least 80euros). The cooling of the vero 10 would cost me two dissipator like the one you saw (35euros max). I would put my exhaust next to the dissipator and my fan recirculating the air should do the job for lowering the Tj.
But Is their a way to keep this safe ? I mean isolating with a resin the connection, linking the heatsink to the ground etc... I don't really know how can I get this really safe.
Sorry to hijack your journal mon ami
foreverflyhi
Well-Known Member
BEAUTIFUL GROW!!!