Cheap and Cheerful DIY using Citizen cobs
- Thread starter JorgeGonzales
- Start date
nevergoodenuf
Well-Known Member
Yes, they work awesome.
CobKits
Well-Known Member
The Dawg
Well-Known Member
Heres my 1st 1812 Complete Grow. The 1812 And 1212 Are Very Close
I Will Be Starting my 1212 Journal This Week
https://www.rollitup.org/t/dawg-house-productions-presents-citizen-cob-1812.922557/
I Will Be Starting my 1212 Journal This Week
https://www.rollitup.org/t/dawg-house-productions-presents-citizen-cob-1812.922557/
CobKits
Well-Known Member
those really wont translate from one garden to another. for all intents and purposes any 50W cob built in last 2 years will perform +/- 5% of any other. and theres too many factors with current, # of cobs per square foot, canopy depth, etc, to make any hard and fast rules about what is 'right' or 'wrong'
cobs do seem to be a lot more forgiving than blurple or hps when kept in the right intensity ranges, just my observation. i think the full spectrum aids in plant vigor
Y you are right.. I can drive a cobs at different mA.
If you can help me: I have one 1212@1.4A and a bigger setup with 4x1212@1A, suggested height?
Btw I am concerned about the final yield since I can grow only in a small 2x2ft (60x60cm) tent and not even for a whole year due to high temps. Let's see how does it go!
hello I did something of very stupid. I tested my 1212 cob before applying them on the heat sink. after about 10 seconds backlighting i saw some smoke from COBS...of course i ready unplugged the power, the cobs were quite hot to the touch. Do i irreparabily damaged their efficiency and factory performances in your opinion, with just a few seconds without heatsink?
Is that the hlg 185 700 or 1400?
DankaDank
Well-Known Member
I miss the bastard !
klx
Well-Known Member
Lesson learned. Lucky it was a $12 chip eh!hello I did something of very stupid. I tested my 1212 cob before applying them on the heat sink. after about 10 seconds backlighting i saw some smoke from COBS...of course i ready unplugged the power, the cobs were quite hot to the touch. Do i irreparabily damaged their efficiency and factory performances in your opinion, with just a few seconds without heatsink?
Yet, it's almost like has never left
CobKits
Well-Known Member
any old light meter or phone app will tell you if the cob is any less bright than its neighborshello I did something of very stupid. I tested my 1212 cob before applying them on the heat sink. after about 10 seconds backlighting i saw some smoke from COBS...of course i ready unplugged the power, the cobs were quite hot to the touch. Do i irreparabily damaged their efficiency and factory performances in your opinion, with just a few seconds without heatsink?
Redoctober
Well-Known Member
Hey @CobKits, love your posts! This is the first I've heard of Luminous Devices, thanks for the heads up! There are so many good COBs coming on the market now, it's awesome to see.
So the CXM is their flagship series I'm guessing, with the Gen 3 being the latest and greatest. You would say it's actually the most efficient when compared to CXB3590 and the new Citizen Gen 6 1818(which I don't see being sold anywhere yet) even though it's significantly cheaper than both? Because that would be amazing!
Also quick question about comparing chips because I have gotten lost in the weeds here (no pun intended). Luminous flux seems to be a number that is on every companies' data sheet, but everyone always uses a different current to measure it, so that number seems either useless or I don't know a way to convert it to a standard current (if that's even possible). My primitive, totally uninformed reasoning on the subject would go something like this:
We'll take 2 different sized chips from different manufacturers as an example, and make up the numbers for ease - Let's just say for arguments sake that the new Gen6 CLU-058 1825 has a luminous flux of 15,000 @ 2amps, and a CXM-22 has a luminous flux of 7,500 @ 1 amp, are those equivalent? Can you divide the 2 amp flux by 2 to match the 1 amp and wind up with an accurate flux measurement? I suspect you're going to tell me it doesn't work that way...
Is luminous flux even a useful number to use as a comparison at all?
What is a good metric to compare COB efficiency between manufacturers and also among chips of the same manufacturer?
...sorry for the barrage of questions
Metacanna
Well-Known Member
Question: I will be running Citizens 1212-048 at 1.4A, 50W each, on Arctic Alpine 11 Pro CPU coolers, rated for 100W. What happens if a fan/ PSU dies? I suppose it all depends on the time it will take until I notice the failure. But let's assume I would be away 24h, would the Cobs survive? If one failed, I suppose the chain would be interrupted and the others would survive, I hope.
The 1212-048 datasheet has the following info on the "Reliability" section
Continuous Operation Test: IF=1080mA Ta=25C (with Al-fin) ×1000hrs / IF=1080mA Tj=140C (with Al-fin) ×1000hrs
Does it mean the COB that was tested runned for 1000hrs at 140C ?? That would be great.
At 10$ per COB, I wonder if it's worth to think too much about it, it might be wiser to have one or two replacements around than to try to figure out expensives and complicated solutions. Plus, these PC fans rarely fail, the PSU might be the weaker link, maybe I should avoid cellphone chargers... a 12V MeanWell is cheap anyway.
Having this said, I don't know how the chain of happenings would be in case one Cobs died, I guess the chance of fire hazard is low, but I feel insecure about this. If anyone experienced fan failure would be cool to know the story.
The 1212-048 datasheet has the following info on the "Reliability" section
Continuous Operation Test: IF=1080mA Ta=25C (with Al-fin) ×1000hrs / IF=1080mA Tj=140C (with Al-fin) ×1000hrs
Does it mean the COB that was tested runned for 1000hrs at 140C ?? That would be great.
At 10$ per COB, I wonder if it's worth to think too much about it, it might be wiser to have one or two replacements around than to try to figure out expensives and complicated solutions. Plus, these PC fans rarely fail, the PSU might be the weaker link, maybe I should avoid cellphone chargers... a 12V MeanWell is cheap anyway.
Having this said, I don't know how the chain of happenings would be in case one Cobs died, I guess the chance of fire hazard is low, but I feel insecure about this. If anyone experienced fan failure would be cool to know the story.
klx
Well-Known Member
Have you already bought the Alpines? If not, why not just 120mm pin fin heat sinks and go passive. All your worries gone...and they are cheap now.
Metacanna
Well-Known Member
No I didn't. I thought about it, but it would increase the cost of cooling. How much are you paying for those pin fin? So far in Europe I didn't find them. Good thing about Alpines is they help to move air, which is very beneficial for small and crowded space like mine. (Me saying by intuition.)
CobKits
Well-Known Member
I have gen 6 1818. i havent ran them side b side yet but they should be right there with the cxm22 gen3. both beat cxb
you have to look at watts. any comparisons i ever do is on a watt basis since all the chips have different voltage profiles
for the same spectrum and same manufacturer, sure. different manufacturers have slightly different test conditions and the data can be biased
but remember lumens are for humans. there are some color temp and CRIs that have less lumens, like a 300k 90 cri, but it has more usable PAR which is what we are after