Luminus CXM-32 Gen3 the next big thing??

muleface

Well-Known Member
help me out here, i dont' think im getting the amps part.

so 4 cmx22's at 320-C1400 = 80 watts per 36v cob (but i could run more cobs becuase the voltage is higher)
and 4 cmx22's at 320-C2100 = 80 watts per 36v cob (only 4 cobs because the voltage is around 150)

how do the amps come into play if i only ran 4 cobs on each array
 

Silver or lead

Well-Known Member
Im gonna run mine at 700ma (4) per 150 watt driver using 3 drivers. I am an efficiency freak. 12 in a 2'x4' tent and likely dimmed to 300 watts at the wall...25 watts per cob or 476 ma
Heck, you could run two cobs per 120mm pin fin at that wattage.

I'll be running 8@~54watts a piece. I might have went lower in wattage had the 105mm pin fins still been available.

They should be here tomorrow, I have electric conduit here for the framework and just need longer screws for attaching cobs to it.
 

Chronikool

Well-Known Member
help me out here, i dont' think im getting the amps part.

so 4 cmx22's at 320-C1400 = 80 watts per 36v cob (but i could run more cobs becuase the voltage is higher)
and 4 cmx22's at 320-C2100 = 80 watts per 36v cob (only 4 cobs because the voltage is around 150)

how do the amps come into play if i only ran 4 cobs on each array
Running in series....and the volts are 50v on the cxm22.
 

verticalgrow

Well-Known Member
help me out here, i dont' think im getting the amps part.

so 4 cmx22's at 320-C1400 = 80 watts per 36v cob (but i could run more cobs becuase the voltage is higher)
and 4 cmx22's at 320-C2100 = 80 watts per 36v cob (only 4 cobs because the voltage is around 150)

how do the amps come into play if i only ran 4 cobs on each array
 

kaivorth

Active Member
Any ETA on when to check back in this thread for sphere testing? Just really interests me to see how accurate the manufacturers specs are compared to our real world usage. These COBs have come such a long way
 

bassman999

Well-Known Member
I just wanna grow weed...:lol:
Me too, but small space or me so ant the most per tf^2 and runnin g them lower with moe cobs means might light and less heat because 2x4x5 tents heat up easy.
If I was powering a big room with 8ft ceilings I would run at 1400ma and still be more efficient and less heat that HPS
 

CobKits

Well-Known Member
Any ETA on when to check back in this thread for sphere testing? Just really interests me to see how accurate the manufacturers specs are compared to our real world usage. These COBs have come such a long way
ok since you guys have been patient... its slow but steady. i made a mount for cobs up top

upload_2016-12-19_23-43-22.png

mounts look like this:

upload_2016-12-19_23-44-47.png

the 3 larger holes fit the ports on the sphere that look like this:

upload_2016-12-19_23-46-10.png

heres a chip mounted on top:

upload_2016-12-19_23-47-1.png

heres the sensor mounting, see that baffle that ensures it only gets reflected light:

upload_2016-12-19_23-49-35.png
 

CobKits

Well-Known Member
light tight! this is with the cobs lit so faint you can look at the dies. below 1mA, i had to finely adjust voltage to get it like that. This should be just what we were lacking in low-current measurements

upload_2016-12-19_23-51-40.png


front port is handy

upload_2016-12-19_23-53-58.png

can take spectrometer readings without stray light

this 3000K 80 CRI is right on the button, here is low current:

upload_2016-12-19_23-55-12.png

when i cranked the current up it went above 3000K and below 80 CRI, so its prob right on the button for both parameters at a certain nominal current

spectrum of 3000k 80cri with zero stray light, nice and smooth. should be good for calculating QERs (spectrometer outputs raw data in 1 nm increments - easily digitized

upload_2016-12-19_23-57-53.png

heres the par meter on the other side of its range (~110W on a CXM22)

upload_2016-12-19_23-59-27.png

meter ranges to 10000, so like 250-300W, pretty good for our purposes. korad meter is handy as it is programmable, and you can also manually select a current and then safely click it on at that current to get a good temperature independent reading. in a perfect world wed mount thermocouples to each chip's Tc measurement point and/or have isothermal waterblock heatsinks to control Tc but we're gonna walk before we can fly.

If we were a real lab wed use a calibrated full-spectrum detector and be able to quantify actual lumens/watt output but for our purposes calibrating the par meter and working with that is adequate.
 
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CobKits

Well-Known Member
so lets break it in with a couple of quick runs

upload_2016-12-20_0-38-36.png

im gonna go out on a limb just by the look of the curves and say that the spot measurements i was doing previously werent too far off. but this is better as it is absolute. provided the ambient temperature is similar and i do a similar method of current ramping and datalogging, i can measure a few cobs today, one tomorrow, three next week and they should all be repeatable and absolute relative to one another as the sphere geometry is fixed, and theres nothing like sensor and chip placement, time of day/room brightness, color of pants im wearing, etc to affect the PAR readings. At this point, while were not really to the standards of a lab, i feel the accuracy is approaching or has exceeded the variability between individual chips from a bin/lot, and is as good as were gonna get for making relative generalizations about the performance of a chip series. That would be a separate test worth doing- pulling 3 or more chips from a lot and running them to see how variable a given bin/lot is.

So what use is this data?
lets compare 2 chips at a fixed efficacy:

upload_2016-12-20_0-50-13.png
a $12 1212 can get you just under 30W at that efficacy
a $17 CXM22 can get you 48W (61% more power) but only costs 42% more than a 1212

remember from previous tests 1212 was the heavyweight leader in PAR/$ at a given efficiency- you just needed to use a lot of them. Here we are getting a scale up at better-than-1212 economics to a more practical sized chip

The economics look stronger when you consider cost of holder, reflector, heatsink, mounting time, etc. Discrete heatsinks will always favor larger chips in installed cost
 
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Chronikool

Well-Known Member
so lets break it in with a couple of quick runs

View attachment 3857580

im gonna go out on a limb just by the look of the curves and say that the spot measurements i was doing previously werent too far off. but this is better as it is absolute. provided the ambient temperature is similar and i do a similar method of current ramping and datalogging, i can measure a few cobs today, one tomorrow, three next week and they should all be repeatable and absolute relative to one another as the sphere geometry is fixed, and theres nothing like sensor and chip placement, time of day/room brightness, color of pants im wearing, etc to affect the PAR readings. At this point, while were not really to the standards of a lab, i feel the accuracy is approaching or has exceeded the variability between individual chips from a bin/lot, and is as good as were gonna get for making relative generalizations about the performance of a chip series. That would be a separate test worth doing- pulling 3 or more chips from a lot and running them to see how variable a given bin/lot is. so what can we learn from this.

So what use is this data?
lets compare 2 chips at a fixed efficacy:

View attachment 3857581
a $12 1212 can get you just under 30W at that efficacy
a $17 CXM22 can get you 48W (61% more power) but only costs 42% more than a 1212

remember from previous tests 1212 was the heavyweight leader in $/PAR at a given efficiency- you just needed to use a lot of them. Here were getting a scale up at better-than-1212 economics to a more practical sized chip

The economics look stronger when you consider cost of holder, reflector, heatsink, mounting time, etc. Discrete heatsinks will always favor larger chips in installed cost
Lookz like i made a good purchase. Cant wait to put them to work.

Great work @CobKits

Citizen cob Artcitecture.jpg
Citizen COB Architecture 1818
 
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