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CobKits

Well-Known Member
ding ding, twist beat me to it.

assuming you need more than one cob 3 1825s are more efficient than 2 3618s at the same price. its like 50% more for 30% more performance... but if you want the best and have to have it.....
 

verticalgrow

Well-Known Member
hlg 240h-2100 and hlg320h-2800 best single driver options if you want to max them out (or cut those currents in half for 2 cobs per driver, eg 240h-1050 and 320h-1400)
Thx but i prefer eff over bigger wattage & a less heavier DIY light.
If the light ever fell it could take out all the plants in 1 hit. :(
So wats the smallest passive pin HS can be used for 1825's since u have them in stock?
 
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CobKits

Well-Known Member
Thx but i prefer eff over bigger wattage & a less heavier DIY light.
If the light ever fell it could take out all the plants in 1 hit. :(
So wats the smallest passive pin HS can be used for 1825's since u have them in stock?
at 50W you would be well under 25W of heat.

i have a bunch of 105s on the way, why dont i run a temp droop test of same chip on 140 then a 105? ill run it out to 100w on the 140 and like 65-70w on the 105
 

CobKits

Well-Known Member
oh geez 20 at least. next time i do a chip ill weigh the amount of paste i put on. ive got a 20g tube and have mounted maybe 30-40 chips so far and am only 1/3 of the way thru it
 

CobKits

Well-Known Member
You damn well better believe that Cree's lm/w #s on the data sheet is the reality , NO inflating===== legal department would have a shit-fit. They have enough problems with t8 retrofit bulbs being recalled twice in a row

possible that Citi is underrating to stay within their specs/ no binning

Also possible your tests aren't dead accurate
FWIW i did a test last night and pulled a separate cxb3590 out of inventory to make sure the one i had wasnt bunk. the old chip looked ok, all the dies lit up. new chip beat it by 5-6% across the board. same batch of chips. i remounted old chip with paste instead of pad to see if that was the difference, nope, it was a dog.

so that said i was surprised to see such variations in chips from same bin same lot. i guess 5-6% could be within DB bin but its definitely at the extremes. in any case the average of the two chips fell right on top of the clu048-1818 curve in the 40-70W range (with clu pulling away above 70W) so my conclusion is the same, that 1818 is a 'match' for CXB at low currents despite the fact that it was slightly 'beating' it on that last run of tests. when youre +/- a few % you are in teh range of chip variation as has been discussed earlier.

in any case thats still a70 cri cxb vs 80 cri everything else, so theres a little handicap built in there as well
 

JorgeGonzales

Well-Known Member
FWIW i did a test last night and pulled a separate cxb3590 out of inventory to make sure the one i had wasnt bunk. the old chip looked ok, all the dies lit up. new chip beat it by 5-6% across the board. same batch of chips. i remounted old chip with paste instead of pad to see if that was the difference, nope, it was a dog.

so that said i was surprised to see such variations in chips from same bin same lot. i guess 5-6% could be within DB bin but its definitely at the extremes. in any case the average of the two chips fell right on top of the clu048-1818 curve in the 40-70W range (with clu pulling away above 70W) so my conclusion is the same, that 1818 is a 'match' for CXB at low currents despite the fact that it was slightly 'beating' it on that last run of tests. when youre +/- a few % you are in teh range of chip variation as has been discussed earlier.

in any case thats still a70 cri cxb vs 80 cri everything else, so theres a little handicap built in there as well
Is DB just the highest bin? You might see more swing than usual if they are just shooting above 13000 lumens and sky is the limit.

But, even in CD bins the swing is ~8% 12000-13000 so is this really a surprise? I mean Citizen as a reference is +/-10%, but who knows what the real variation is. Be fun to see a handful of those tested if you haven't.
 

CobKits

Well-Known Member
there are DDs out in the wild now but they still dont list it as as an order code. possible that the one i hve thats testing higher is actually in DD bin but they sold it as DB. nobody here who has the DDs will cough one up for testing so i guess well never know

im putting together some setups, next time i have 4 citi chips that are the same installed ill run them
 
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