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Millsie

Well-Known Member
Still waiting eagerly for those 3618 spread tests. Would you consider doing it in a 4x4, hanging a bit higher than 12'? So as to get an idea to how they would work in a large open canopy with several lights? The drivers we are working with should work real neat for 3618 ;)

Also very happy to say that spanish customs look about ready to release my 1825s after almost a month of fuckin around:wall:
@Millsie looking at running them around 160w each, just like u, but on hlg185 48A. I think these drivers are going out of production but i really like them for a paralell conection prohect further down the road.
What watt/amp where you hoping to run the 3618's at? If there at 100w+ I would say 12" would roughly be the minimum - as its a fuck load of light

You mentioned 'parallel connection' what do you mean by this?

You'll love those 1825's and they'll pair up with a hlg185's real well and even be brighter than mine!
 

CobKits

Well-Known Member
Still waiting eagerly for those 3618 spread tests. Would you consider doing it in a 4x4, hanging a bit higher than 12'?
by design if youre running these at 320W you need more than 12". id say they could light up a 4x4@ 24-36" we might need to lose the reflector. ive only got 3x3 and 5x5 tents to test, no 4x4.
 

Rocket Soul

Well-Known Member
Id love to see it in open area, but tents good aswell. And yeah theyd need to go high.
@Millsie would probably be running the 3618 at 2.1 amps for just under 250w. Will try to work exclusively on 240s at 2.1, they fit really well around the voltage and popular drive currents on most chips even when you run paralell(share amps) for pros and cons on paralell connections i wont clog up this thread, sure theres info in the stickied power thread.
 

CobKits

Well-Known Member
thats the elegant beauty of the 3618s- 1 cob+1 driver. forget about parallel/series debate. its also a system which is pretty damn familiar to the hid crowd (one bulb one ballast)

oh boy just wait till those 480W CC meanwells come out

Big Meanies gonna throw a hurtin on some 600W HPS with a single cob
 

CobKits

Well-Known Member
1818 is the best match for cxb
1212 is 1/2 the price of 1818 and about 3/4 of the wattage of 1818/cxb at a given efficacy
so for example a 1212 at 45W is about as efficient as CXB or 1818 at 60W
 
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HolyGhost23

Well-Known Member
ill special order it for you for $80 but im not stocking that- the hlg-185 is identical for our application and is 2/3 the price
what about anything 185-54..dont care if its hlg hep what have you.. just so long as it can do 185W and 54V.. or slightly better
 

CobKits

Well-Known Member
yeah id be into hlg-185h-54 its a great 200W solution for an 1825 single cob
 
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Victor6634

Well-Known Member
1818 is the best match for cxb
1212 is 1/2 the price of 1818 and about 3/4 of the wattage of 1818/cxb at a given efficacy
so for example a 1212 at 45W is about as efficient as CXB or 1818 at 60W
I know the difference between the 1212 and the. 1818 my question was about the 1812 and the 1818
 

CobKits

Well-Known Member
FWIW i just put together some 1825s (2700k-90cri - the least "efficient" ("efficacious?") ones i stock) on some 140x80 pinfins

i wanted to run one out on voltage to see what it would look like thermally

i have a 2 x 140/80 rack with a 185-48A on it with some 5000Ks- gonna swap these 2700ks in

after a good half hour on the bench (cob down/pins up/on aluminum rails), at 2250 mA (nominal current for that chip and a few percent above the 2125A the meanwell can feed it when split with another cob), the voltage is stable at 51.86-51.88V

lt was dropping 1/100 of a volt every few minutes but seems to have leveled out, i dont see it going below 51.80

this is in completely still air, ambient temp 23C.

so you can see that even though we may be denting the efficiency of the chip we are well within its 105C Tc and 140C Tj limits. In fact my IR thermometer reads 74C behind the chip on the heatsink which is right in line with citi predicted data

upload_2016-10-11_2-36-18.png

upload_2016-10-11_2-40-19.png

note that we are at 116 lm/W at Tc=75C, the chip is 121 lumens per watt at 50 Tc (2700k 90 cri is what it is- this is a strict bloom booster for me so im getting what i want) I'm assuming a more efficient chip like a 5000K 70 cri would put less heat out the back, one of the ones im swapping is a 5000k 70cri, ill try to run that on the bench tomorrow. it is 163 lm/W under that temp/voltage condition. im not expecting that dramatic of a thermal difference, while the phosphor plays a role in "lumen" creation that doesnt tell the whole tale of light emission/efficiency since lumens arw weighted by wavelength (esp a 2700k which is low in the greens). at the end of the day they are the same die configuration so im expecting the 5000k to have less of a heat advantage than the lumen values would indicate

im not going to officially endorse running these two per hlg-185-48A, 75C heatsink is hot and will burn your hand. operating in that range is up to you but its good to know in a pinch we can run that hard on the pinfins while keeping in spec, and it should give good confidence to anyone looking to push these to 80+W. the tiniest airflow from a fan should drop the pinifin temp considerably

and thats current gen... wait till next gen citis come out

· Performance: 2% ~ 8% increase
· Thermal Resistance: 5% decrease

· TcMax: from 105degC to 120degC
· TjMaxx: from 140degC to 150degC

100W on pinfins will be the norm soon enough. with those improvements they wont be cracking a sweat at 100W
 

CobKits

Well-Known Member
I know the difference between the 1212 and the. 1818 my question was about the 1812 and the 1818
well what is "better"?

1812 is $6 cheaper per chip
1818 is ~7% more efficient but more expensive

upload_2016-10-11_3-4-57.png

1818 def a way better voltage profile for a hlg-48A driver if you want to run them hot
1812 will top out at 1250 mA/67W
1818 will go to 1900 mA/102W on same driver
(1825 goes to 2700 mA/145W)
 

CobKits

Well-Known Member
i just threw the other 2700k on to do a quick test, after 10 min its at 51.90V its tracking almost identical to the other one. i love citi's fine japanese tolerances, so consistent :)
 

Nenno44

Well-Known Member
Hey cobby i was thinking about running 10 1825's in the range of 40-60 watts, what drivers would you recommend using? and how many of these could i wire in series with a bjb holder?
 

Rocket Soul

Well-Known Member
FWIW i just put together some 1825s (2700k-90cri - the least "efficient" ("efficacious?") ones i stock) on some 140x80 pinfins

i wanted to run one out on voltage to see what it would look like thermally

i have a 2 x 140/80 rack with a 185-48A on it with some 5000Ks- gonna swap these 2700ks in

after a good half hour on the bench (cob down/pins up/on aluminum rails), at 2250 mA (nominal current for that chip and a few percent above the 2125A the meanwell can feed it when split with another cob), the voltage is stable at 51.86-51.88V

lt was dropping 1/100 of a volt every few minutes but seems to have leveled out, i dont see it going below 51.80

this is in completely still air, ambient temp 23C.

so you can see that even though we may be denting the efficiency of the chip we are well within its 105C Tc and 140C Tj limits. In fact my IR thermometer reads 74C behind the chip on the heatsink which is right in line with citi predicted data

View attachment 3801928

View attachment 3801929

note that we are at 116 lm/W at Tc=75C, the chip is 121 lumens per watt at 50 Tc (2700k 90 cri is what it is- this is a strict bloom booster for me so im getting what i want) I'm assuming a more efficient chip like a 5000K 70 cri would put less heat out the back, one of the ones im swapping is a 5000k 70cri, ill try to run that on the bench tomorrow. it is 163 lm/W under that temp/voltage condition. im not expecting that dramatic of a thermal difference, while the phosphor plays a role in "lumen" creation that doesnt tell the whole tale of light emission/efficiency since lumens arw weighted by wavelength (esp a 2700k which is low in the greens). at the end of the day they are the same die configuration so im expecting the 5000k to have less of a heat advantage than the lumen values would indicate

im not going to officially endorse running these two per hlg-185-48A, 75C heatsink is hot and will burn your hand. operating in that range is up to you but its good to know in a pinch we can run that hard on the pinfins while keeping in spec, and it should give good confidence to anyone looking to push these to 80+W. the tiniest airflow from a fan should drop the pinifin temp considerably

and thats current gen... wait till next gen citis come out

· Performance: 2% ~ 8% increase
· Thermal Resistance: 5% decrease

· TcMax: from 105degC to 120degC
· TjMaxx: from 140degC to 150degC

100W on pinfins will be the norm soon enough. with those improvements they wont be cracking a sweat at 100W
Ive been in love with the idea of 1825 (or vero 29c version) on the 100w pinfins for some time now, good to know even a smaller heatsink will manage
well what is "better"?

1812 is $6 cheaper per chip
1818 is ~7% more efficient but more expensive

View attachment 3801941

1818 def a way better voltage profile for a hlg-48A driver if you want to run them hot
1812 will top out at 1250 mA/67W
1818 will go to 1900 mA/102W on same driver
(1825 goes to 2700 mA/145W)
As for the 1825 on a hlg185: youve run it up to 2700mA, thats when its thermally stable? This is what im doubting about: since cold start voltage of the chip is slightly higer than when its thermally stable how would one set this up for starting and reaching highest amp without fiddling with the dimmer and voltage? Will feeding it a high current from the start stop it from lighting up? Or if get it lit up , could i squeeze a few more watts out of it by tweaking the amps?
 

CobKits

Well-Known Member
As for the 1825 on a hlg185: youve run it up to 2700mA, thats when its thermally stable?
no thats when it hits 53.5V and tops out voltage on the driver. it lights up fine. as long as you get above the 48V or whatever they will light up

thermal stability is a different animal and depends on heatsink.
 

Victor6634

Well-Known Member
PRODUCT PRICE QUANTITY TOTAL
× Citizen CLU048-1818 80CRI (choice of color temps)
Color Temperature 3500K. Quantity. 14. $26.00 $364.00
× Citizen CLU048-1818 80CRI (choice of color temps)
Color Temperature:
4000K. Quantity 14. $26.00 $364.00
× Arctic thermal pads for Citizen CLU048 series $1.00 Quantity. 28. $28.00
× Ideal 50-2100AN reflector adapter for Angelina reflector+Citizen CLU048 $1.00 Quantity 28. $28.00
× LEDiL Angelina reflector for CREE CXB and Citizen CLU048 using Ideal holders $5.50 Quantity. 28. $154.00

@CobKits do you have all this in stock please let me know?
 
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