Cheap and Cheerful DIY using Citizen cobs

[JorgeGonzales]

Good job on those charts

Thanks, it's just a front end on their simulator, with some digitized spectrum chart data hacked in to do the efficiency calculations. There's also lots of actual measurements spread around the site, but spread is the key word there.

But it's useful to do a quick PPF or driver calculation, hopefully. Probably conservative on the PPF, but useful to compare relative performance between Citizens.

 

[Johnnycannaseed1]

Yeah I could see you would of had to put a load of work in to get those figures, sometimes when people see the end result they think it came easy, clearly you have put some serious hours into this so well done and thanks

 

[Copernicunny]

I see that now, I was basing my thinking on my HLG 185h -C1050b. So the 240H would be the better choice?

I mean the 240 would work. If you're American this might not help at all, but it's probably worth it to wait and see what kind of voltage the ELG-C200 runs.

 

[nevergoodenuf]

None of the holders you can get allow you to run over 150 volts safely. I am not saying your lights won't work, but you would need to use the larger CLU058 holder to safely run 2 maybe 3 COBs.
Wire choice is also very important when you are running multiple COB's on CC drivers. If this is your first build, stick to the smaller drivers until you have a light or 2 built without any wiring issues.
What I have seen with the Citizens is they are like soldering to an egg shell. They are the hardest COB's I have trying soldering to.

 

[guod]

None of the holders you can get allow you to run over 150 volts safely.

the voltage over a cob holder can never exceed the voltage of the cob inside the holder.
except there is no cob in the holder. and if this happens to you you should better stop smoking.

 

[JorgeGonzales]

the voltage over a cob holder can never exceed the voltage of the cob inside the holder.
except there is no cob in the holder. and if this happens to you you should better stop smoking.

I am literally too high to know what this means. That is all.

 

[BOBBY_G]

None of the holders you can get allow you to run over 150 volts safely.

good thing we dont need to. even the 100V 3618s can be safely run a dozen or more at a time in parallel, off a single power supply and still be in spec

 

[JorgeGonzales]

good thing we dont need to. even the 100V 3618s can be safely run a dozen or more at a time in parallel, off a single power supply and still be in spec

My own measurements of vF between cobs running in series say this is probably fine. The cobs I've checked are really well matched, but I'm still hesitant to just say "run parallel" to everybody who asks. Current hogging and thermal runaway are actual things.

 

[BOBBY_G]

My own measurements of vF between cobs running in series say this is probably fine. The cobs I've checked are really well matched, but I'm still hesitant to just say "run parallel" to everybody who asks. Current hogging and thermal runaway are actual things.

As are fuses...

but yes i hear you it would be great if ideal made a 250V holder for 058 series

 

[Organic Miner]

So what will remedy this problem. More drivers with only 2 cobs on each driver instead of 4 or run 4 cobs per driver but only at 1050Ma. Told yall I'm a newb!

Not to throw a wrench in here, but I did the math 4 1212's required more voltage (147) then the meanwell 1400 could supply. This is why I special order 1300 am drivers from LSD, so I could exactly what you are talking about and not over drive the drivers. I ended up having to buy 20 to make the deal, but hell I needed 18 to do my room so now I have 2 spares. I didn't feel comfortable overdriving the 1040 even though many here say it can be done. My 2 cents.

 

[Ledder42O]

I am literally too high to know what this means. That is all.

i think he forgot the word when and meant except when there is no cob in the holder. serial circuit, so like the cob inside it, the holder doesn't get the total circuit voltage.

 

[JorgeGonzales]

i think he forgot the word when and meant except when there is no cob in the holder. serial circuit, so like the cob inside it, the holder doesn't get the total circuit voltage.

You are right, obviously, the voltage between the +/- contacts on the holder won't exceed the voltage drop of the cob, but I believe the unresolved question is arcing between the heat sink and high voltage line, for instance.

Personally, I measured the gap between the BJB contacts and my heatsinks, saw it was over 1mm and said screw it. That's too far for ~200V to jump, and nothing a bit of carefully applied liquid electrical tape couldn't beef up if somebody was worried, but I'd never recommend anybody use them in series.

There's a thread about it somewhere around here, started by @BOBBY_G saying the sky is falling and we should all run parallel...here we go:

https://www.rollitup.org/t/bjb-holders-voltage-spec-is-too-low-for-series-configuration.912573/#post-12703425

 

[Ledder42O]

What I have seen with the Citizens is they are like soldering to an egg shell. They are the hardest COB's I have trying soldering to.

what does that mean, like soldering to an eggshell, can you break the cob or something?

i had a good laugh reading this citizen pdf:
http://ce.citizen.co.jp/lighting_led/dl_data/tech/en/Ref_P2468_0313_R3(0514).pdf

Yeah I could see you would of had to put a load of work in to get those figures, sometimes when people see the end result they think it came easy, clearly you have put some serious hours into this so well done and thanks

echoed for truth, thanks Jorge for this thread.

 

[MrTwist1]

I'm waiting for the answer myself cause I've chatted with a guy running 20 clu right now with hlg-185h-1400b. He's pulling 5-6lbs per grow

I hate to be a downer but isn't 20 x1212 @1400mA (50w each) 1000W total?! I call bullshit on 5-6lbs per run.

 

[BOBBY_G]

 

[BOBBY_G]

I hate to be a downer but isn't 20 x1212 @1400mA (50w each) 1000W total?! I call bullshit on 5-6lbs per run.

he didnt say 1212
20 1818s or 1825 are 1480W which would put him under 2 g/watt at 6 lbs

 

[JorgeGonzales]

he didnt say 1212
20 1818s or 1825 are 1480W which would put him under 2 g/watt at 6 lbs

Oh he definitely meant 1212s. He's been asking how it's possible to run 4 1212s on a 200W driver for awhile now.

Good to know the 1212s can hit 2.7 gpw at 50W. Astonishing!

 

[MrTwist1]

he didnt say 1212
20 1818s or 1825 are 1480W which would put him under 2 g/watt at 6 lbs

As Jorge said, all the preceding talk was about 1212s.

 

[BOBBY_G]

well, guy asking questions about 1212s says his clu friend is pulling xx... doesnt necessarily mean his buddy uses 1212s...

 

[nevergoodenuf]

@Ledder42O I delaminated the soldering pad when I first tried soldering to it.