PPFD measurements on CXB3590 builds

coreywebster

Well-Known Member
Sorry, I thought there was a standard of one square meter. That was what I was needing is the measurements of both power supplies at their full potential on one square meter.
8x cxb3590 (3500k) @700mA

CXB3590CD36V3500K 8 COBS @0.7A ON 1.813 PROFILE HEATSINK
1 SQ.M. CANOPY 95% EFFICIENT DRIVER @11 CENTS PER KWH
Total power watts at the wall: 192.63
Cobs power watts: 183

Total voltage forward: 262
Total lumens: 37952
Total PAR watts assuming 10% loss: 105
Total PPF: 488.25
PPFD based on canopy area: 488.25
PAR watts per sq.m.: 105.0
Cob efficiency: 64.01%
Power watts per sq.m.: 183.0
Voltage forward per cob: 32.72
Lumens per watt: 207.39
Heatsink riser thickness / number of fins / fin's length: 0.3in/6/0.95in
Heatsink area per inch: 100.94 cm^2
Total heat watts: 66
umol/s/W / CRI: 4.65 / Estimated
Heatsink length passive cooling @120cm^2/heatwatt: 78 inches
Heatsink length active cooling @40cm^2/heatwatt: 26 inches
COB cost dollar per PAR watt: $3.63
Electric cost @12/12 in 30 days: $8.13
Electric cost @18/6 in 30 days: $11.94
Cost per cob: $47.62
Heatsink cost per inch cut: $0.66
Total cobs cost: $381
Total heatsink passive cooling cost: $51
Total heatsink active cooling cost: $17
 

coreywebster

Well-Known Member
8X CXB3590(3500k) @1400mA

CXB3590CD36V3500K 8 COBS @1.4A ON 1.813 PROFILE HEATSINK
1 SQ.M. CANOPY 95% EFFICIENT DRIVER @11 CENTS PER KWH
Total power watts at the wall: 411.58
Cobs power watts: 391

Total voltage forward: 279
Total lumens: 71373
Total PAR watts assuming 10% loss: 198
Total PPF: 920.7
PPFD based on canopy area: 920.7
PAR watts per sq.m.: 198.0
Cob efficiency: 56.34%
Power watts per sq.m.: 391.0
Voltage forward per cob: 34.89
Lumens per watt: 182.54
Heatsink riser thickness / number of fins / fin's length: 0.3in/6/0.95in
Heatsink area per inch: 100.94 cm^2
Total heat watts: 171
umol/s/W / CRI: 4.65 / Estimated
Heatsink length passive cooling @120cm^2/heatwatt: 203 inches
Heatsink length active cooling @40cm^2/heatwatt: 68 inches
COB cost dollar per PAR watt: $1.92
Electric cost @12/12 in 30 days: $16.8
Electric cost @18/6 in 30 days: $24.95
Cost per cob: $47.62
Heatsink cost per inch cut: $0.66
Total cobs cost: $381
Total heatsink passive cooling cost: $134
Total heatsink active cooling cost: $44
 

coreywebster

Well-Known Member
This is using the cob calculator from a thread on here somewhere.

The second one @1400 mA does not take into account two drivers so divide the forward voltage, cob watts ect by 2

Hope that's of use to you.

EDIT..

PER DRIVER

Total power watts at the wall: 205.26
Cobs power watts: 195
Total voltage forward: 140

Total lumens: 35595
Total PAR watts assuming 10% loss: 99
Total PPF: 460.35
PPFD based on canopy area: 460.35
PAR watts per sq.m.: 99.0
Cob efficiency: 56.34%
 

CobKits

Well-Known Member
Sorry, I thought there was a standard of one square meter. That was what I was needing is the measurements of both power supplies at their full potential on one square meter.
while the units of PPFD are per square meter, it is a spot measurement by nature and there is no requirement to measure it in a one square meter space. Kind of like how you can read miles per hour with your speedometer without driving a whole hour
 

krankenphleger

Active Member
while the units of PPFD are per square meter, it is a spot measurement by nature and there is no requirement to measure it in a one square meter space. Kind of like how you can read miles per hour with your speedometer without driving a whole hour
I understand what you are saying about taking spot readings. When you buy a car the horse power of the motor determines how fast the car will travel measured in MPH or KPH. That is basically where I am coming from and I am sure you know this. It would seem that the light industry would come up with a measurement standard, for instance, a nine point check per square meter just to give an idea what the average PPFD of a given light and power source would be.
 
Top