bicit
Well-Known Member
Estimate is 20 days, however I received my package 7 days after placing my order with china post. Worked out very nicely.
COB efficiency Spreadsheets
- Thread starter nogod_
- Start date
Getgrowingson
Well-Known Member
i got mine in 3 days via dhl. fastesrt shipment from china yet. i ordered cxb3590 3000k CB. they came in the original package. what should the little code in the corner say? i herd someone got a sample batch and wasnt happy. just want to make sure their legit
Getgrowingson
Well-Known Member
they sure look the part and after alot of research i can only assume they are legit. Supra checked em out and proved they were legit as well as a few others. but eventually i will be checking them. I need heatsinks still though before that will happen
SupraSPL
Well-Known Member
DHL is very fast but they hit me with a 4% customs fee randomly. The drove over my lenses with a fork lift and delivered it torn open and mashed. Luckily seller replaced. China Post has been treating me great lately, so much cheaper ~7-10 days, but it is nerve wracking either way.
Getgrowingson
Well-Known Member
yea i got nailed with a customs fee as well. Kingbrite helped me out and put the value of the items VERY low or else i would have been on the hook for a lot of taxes.
cityworker415
Well-Known Member
Dude, seriously it's not bad 2 weeks. .. if it goes well if not 2 months for a wet sack to be at your door
Sent from my SM-G900V using Rollitup mobile app
salmonetin
Well-Known Member
...Supra ...questions about your spreadsheets...
example
vero 29 3000k ........-0.50????...... 320...LER?.... 28,21 ...cost per unit?? (maybe same date ...and maybe ...price from...xxxx)???....
...factor column...power factor values?....
...thanks in advance...
...maybe a few words about graphics from datasheet - spreadsheet columns relations...
saludos
example
vero 29 3000k ........-0.50????...... 320...LER?.... 28,21 ...cost per unit?? (maybe same date ...and maybe ...price from...xxxx)???....
...factor column...power factor values?....
...thanks in advance...
...maybe a few words about graphics from datasheet - spreadsheet columns relations...
saludos
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SupraSPL
Well-Known Member
Good questions Salmonetin, originally I just made the spreadsheets for my own use and I never made them very user friendly
-The minus 0.50 represents the decrease in Vf as the temp rises from 25C to 50C.
-$28.21 is the current price at digikey. We might be able to get them cheaper from Kingbrite at some point
-The "factor" column represents "current droop" for Veros and represents combined current/temp droop for Cree CX series. I derive those numbers by counting pixels from the PDF data. I have always used a Tj of 50C across the board because I think that is a fair goal for our cooling. However, when COBs are run hard they are likely above that and run soft they can be below that. To make things more confusing, in some charts manufacturers started using Tc data rather than Tj data, and some parts of their PDF still refer to Tj. So it is not very clear unfortunately. That is an imperfect part of my system, but it gets us close and makes the numbers more easily comparable.
Cree CXB3070 example:
-There are several different LERs floating around from Mr Flux, Stardustsailor and Alesh. As far as I know Alesh numbers are the most up to date and includes data about the changes in the Vero V2.0 so I have been using those. Thank you @alesh! PS are these LER figures for 400-700nm or 380-780nm?
-The minus 0.50 represents the decrease in Vf as the temp rises from 25C to 50C.
-$28.21 is the current price at digikey. We might be able to get them cheaper from Kingbrite at some point
-The "factor" column represents "current droop" for Veros and represents combined current/temp droop for Cree CX series. I derive those numbers by counting pixels from the PDF data. I have always used a Tj of 50C across the board because I think that is a fair goal for our cooling. However, when COBs are run hard they are likely above that and run soft they can be below that. To make things more confusing, in some charts manufacturers started using Tc data rather than Tj data, and some parts of their PDF still refer to Tj. So it is not very clear unfortunately. That is an imperfect part of my system, but it gets us close and makes the numbers more easily comparable.
Cree CXB3070 example:
-There are several different LERs floating around from Mr Flux, Stardustsailor and Alesh. As far as I know Alesh numbers are the most up to date and includes data about the changes in the Vero V2.0 so I have been using those. Thank you @alesh! PS are these LER figures for 400-700nm or 380-780nm?
alesh
Well-Known Member
380-780 nm. Any figures I posted are in this range unless specified otherwise. LER has to be done over the w̶h̶o̶l̶e̶ ̶r̶a̶n̶g̶e̶ range the luminosity function is defined in.
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alesh
Well-Known Member
LER should be calculated over the range the luminosity function is defined in.
Shig87
Member
View attachment 3444601
Or alesh
do you got a chart like this for the CXB 3070 AD & the CXB 3590 aswell you like to share with us?
Or alesh
littlejacob
Well-Known Member
Bonjour
I just saw that the vero 5000k V1 is a bit (nano bit) more efficient than the V2! I have to buy some V10 soon is there some Vero10 V2? If there is not V2 are they going to be available soon or not...
Thanks
I just saw that the vero 5000k V1 is a bit (nano bit) more efficient than the V2! I have to buy some V10 soon is there some Vero10 V2? If there is not V2 are they going to be available soon or not...
Thanks
alesh
Well-Known Member
The difference between v1 and v2 5000K is within the margin of error. They're probably one and the same.
Vero10 v2 are already available.
robincnn
Well-Known Member
Posting here as i did not want to confuse AP
https://www.rollitup.org/t/led-cob-bar-project.874955/page-3#post-11703668
Ok i may be wrong. I will try to find why. Here was my assumption.
https://www.rollitup.org/t/flip-chip-opto-high-power-build-thread.863947/page-4#post-11412494
Supra mentioned
A 1 watt, 100% efficient 3000K CXA would put out 325 lumens, LER 325lm/W
325lm/w means 48% light and 52% goes to heat. So .48 watt of light