COB efficiency Spreadsheets

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HydrOGdeluxe

Member
OneHitDone said:
A lot of growers with larger rooms don't have a reflective wall right up against the fixture so tent #'s are useless in that situation.
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Not as useless as black wall tests, which are more like a situation with reflective walls and no overlapping lights in a large space. It's just unrealistic to compare to mediocre hps setups. I know many growers with large rooms and have no doubt they realize too comparing hps to led using black walls is almost childish. It would result in a large difference between hps hoods with a narrow beam and something wider already. One of my favorite growers uses gavita-ePapilon-gavita. The epap has a much wider footprint. Comparing the two with black walls and concluding one is better than the other would just be wrong.

The sphere is used to exclude variable, you can't do that simply by using black walls. All that is left is to test realistic situations.
 
P

PurpleBuz

Well-Known Member
HydrOGdeluxe said:
Not as useless as black wall tests, which are more like a situation with reflective walls and no overlapping lights in a large space. It's just unrealistic to compare to mediocre hps setups. I know many growers with large rooms and have no doubt they realize too comparing hps to led using black walls is almost childish. It would result in a large difference between hps hoods with a narrow beam and something wider already. One of my favorite growers uses gavita-ePapilon-gavita. The epap has a much wider footprint. Comparing the two with black walls and concluding one is better than the other would just be wrong.

The sphere is used to exclude variable, you can't do that simply by using black walls. All that is left is to test realistic situations.
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Black walls does not substitute for sphere testing, Black walls tests "distribution" without the variability of reflection from all sorts of different walls. Its the only real way to determine overlap coverage without measuring on each specific site layout. Sphere testing gives an overall light output from the lamp. Two very different things.

Please think about what I have said before replying its getting tiresome trying to explain for the umpteenth time to different people.
 
H

HydrOGdeluxe

Member
PurpleBuz said:
are you testing the tent or the light or the reflector ?
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What you claimed black wall tests illustrate, how much light the light delivers to the canopy. The tent or space with refelective walls is fixed, the light is variable, so is the footprint in an unlimted space with no reflection and walls. The space is fixed, the lights you put in it you test.

The ppfd of a single cob at the edges of the foot print is with reflective walls similar to what it would be with overlap, minus the relatively constant wall reflection. I'm not looking to replace or compare to some half-assed hps grow op. In a multiple cob grow or large hps grow there should be at least reflective walls or overlap.

You measure total light only either way, and from that you clearly cannot derive how much was reflected by the tent or reflector. In case of hps the light and the reflector is the same entity so separating those is just... I read enough here to know where attempts to have real discussions go and you're going to stick to your opinion anyway.
 
OneHitDone

OneHitDone

Well-Known Member
Hey guys, how about a new standard for all lighting manufacturers to adhere to - say 5 tests?
1 - Sphere
2 - Black Space
3 - Mars Hydro Tent
4 - White Paint walls
5 - High end Tent

And maybe a 6th for some or us - A vertical wall Footprint :hump:
 
JorgeGonzales

JorgeGonzales

Well-Known Member
PPF is the one true god. As far as the rest, well that's why handheld meters exist. Infinite variety of setups. I can see both sides to the tent argument.

For testing footprint uniformity, no tent is fairest. For testing average PPFD, in a tent or out it's so fucked by lenses and reflectors as to make comparisons pointless.

Anyway, refreshing argument for this place.
 
BM9AGS

BM9AGS

Well-Known Member
wietefras said:
It pulls 1210W when boosted including driver losses. We don't include driver losses for leds either though and the efficiency of those is similar.

That PPFD matrix was for the light running at 1000W. When boosted you get over 900umol/s/m2 average.
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Ok, but the hood used in that test is no where to be found online. Unless it's name changed from prototype to production which still doesn't identify what good was used.
 
wietefras

wietefras

Well-Known Member
PurpleBuz said:
It tells us what light actually hits the canopy in a large open grow space or in a greenhouse and its distribution pattern. Based on that one can determine needed overlap coverage. Following that one can estimate how much light can be recovered with side reflection.
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That's what you use isodiagrams are for:
HR96.png
 
wietefras

wietefras

Well-Known Member
JorgeGonzales said:
PPF is the one true god. As far as the rest, well that's why handheld meters exist. Infinite variety of setups. I can see both sides to the tent argument.

For testing footprint uniformity, no tent is fairest. For testing average PPFD, in a tent or out it's so fucked by lenses and reflectors as to make comparisons pointless.
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Indeed I would also suggest using with PPF (from the fixture!) and factor in your own wall losses to calculate average PPFD.

people go really nuts over the smallest things though. When you look at the specs from Cree, they can vary by 7% plus or minus. If you compare grow tents with different reflective walls the difference is not going to to be bigger than that. Only if you use something odd like black walls then you end up with PPFD figures that are so far off what you would get in reality that it becomes useless.

Anyway, refreshing argument for this place.
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Heh
 
wietefras

wietefras

Well-Known Member
BM9AGS said:
Ok, but the hood used in that test is no where to be found online. Unless it's name changed from prototype to production which still doesn't identify what good was used.
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Gavita M reflectors.

It doesn't matter anyway, since with a regular reflector and in a 5'x5' tent you get similar figures. The problem with that square tent is that the uniformity isn't great since the footprint is more rectangular. That's why they designed the tent to better fit the footprint, but the amount of light hasn't changed.
 
JorgeGonzales

JorgeGonzales

Well-Known Member
wietefras said:
Indeed I would also suggest using with PPF (from the fixture!) and factor in your own wall losses to calculate average PPFD.

people go really nuts over the smallest things though. When you look at the specs from Cree, they can vary by 7% plus or minus. If you compare grow tents with different reflective walls the difference is not going to to be bigger than that. Only if you use something odd like black walls then you end up with PPFD figures that are so far off what you would get in reality that it becomes useless.


Heh
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The thing is, the amount of uselessness remains steady for all lights tested. But it's just a test for that light over that exact footprint.

Cree pulled the same shit with their magical 500W replacement for a 1000W bulb.

And yeah, we don't talk about wall losses because it's implied they aren't part of the efficiency numbers, unless you are selling lamps. Too many ways to build, too many drivers to use at too many loads, etc.
 
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T

todd86

Active Member
20160722_212208.jpg 20160722_212220.jpg Hi i was provided this when I purchased my cobs from Kingbrite.

https://solutions.3m.com/wps/portal/3M/en_US/Adhesives/Tapes/Promotions/Enabling-Design-and-Process-Freedom/Products/~/3M-Double-Coated-Tissue-Tape-9448A?N=7582978+3294280710&rt=rud

3m 9448A Double coated Tissue Tape, its the same size as the Cobs, do I use this instead of thermal grease?

......................

kingbrite has confirmed this is what the double sided tape is for.

Do you think the Tape will do as good a job as thermal Grease? , Im using passive cooling.
 
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BM9AGS

BM9AGS

Well-Known Member
wietefras said:
Gavita M reflectors.

It doesn't matter anyway, since with a regular reflector and in a 5'x5' tent you get similar figures. The problem with that square tent is that the uniformity isn't great since the footprint is more rectangular. That's why they designed the tent to better fit the footprint, but the amount of light hasn't changed.
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M reflector designed for a 5.9x3.6" room
So your reference was bogus.
image.png

Here is the only measured ppfd chart I've seen for 4x4 with gavita de at 1000w
image.png
 
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PSUAGRO.

PSUAGRO.

Well-Known Member
[/QUOTE="todd86, post: 12795548, member: 919833"]View attachment 3738479 View attachment 3738480 Hi i was provided this when I purchased my cobs from Kingbrite.

https://solutions.3m.com/wps/portal/3M/en_US/Adhesives/Tapes/Promotions/Enabling-Design-and-Process-Freedom/Products/~/3M-Double-Coated-Tissue-Tape-9448A?N=7582978+3294280710&rt=rud

3m 9448A Double coated Tissue Tape, its the same size as the Cobs, do I use this instead of thermal grease?

......................

kingbrite has confirmed this is what the double sided tape is for.

Do you think the Tape will do as good a job as thermal Grease? , Im using passive cooling.[/QUOTE]






I would use good quality thermal grease/paste/compound imo..............especially in a passive setup



good luck
 
salmonetin

salmonetin

Well-Known Member
....nahhh ...reflowed its best.. cobs reflowedssss..lol :fire:

...soldered dont fall...:lol:;)... (im jokin a bit...)... i and my bad english... lol

pd...le falto el espectro de la gavita....realmente del philips master greenpower plus DE 1000 W...



....notice the pic on 820-830 nm.... ese Guoddd...;)
...they dont show the pic on uv... but i adivine one on 320-340 nm... maybe its only efects of the red wine....:mrgreen:



:peace:

Saludos
 
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guod

guod

Well-Known Member
COB-KILLER...
3M™ Double Coated Tissue Tape 9448A
  • Good high temperature holding power
  • Nameplate bonding, plastic film lamination/bonding, splicing, and foam bonding
  • Adhering, joining, affixing, bonding, mounting, holding, laminating, and attaching
------------------------------------------------------------------------------------------------------------------
usefull up to 10 Watt
3M™ Thermally Conductive Adhesive Transfer Tape 88XX
Applications‎
IC Packaging Heat Conduction‎ , Heatsink-Thermal Interface Attachment‎ , Battery Thermal Management‎ , LED Lighting Thermal Management‎ , Heatsink-Thermal Interface-Non Bonding‎ , Flex Bonding‎ , Thermal Interface-Damping-Cushioning‎

full list
http://solutions.3m.com/wps/portal/3M/en_US/Electronics_NA/Electronics/Products/Electronics_Product_Catalog/~/Thermally-Conductive-Interface-Tapes?N=8704987
 
PSUAGRO.

PSUAGRO.

Well-Known Member
guod said:
COB-KILLER...
3M™ Double Coated Tissue Tape 9448A



    • Good high temperature holding power
    • Nameplate bonding, plastic film lamination/bonding, splicing, and foam bonding
    • Adhering, joining, affixing, bonding, mounting, holding, laminating, and attaching
------------------------------------------------------------------------------------------------------------------
usefull up to 10 Watt
3M™ Thermally Conductive Adhesive Transfer Tape 88XX
Applications‎
IC Packaging Heat Conduction‎ , Heatsink-Thermal Interface Attachment‎ , Battery Thermal Management‎ , LED Lighting Thermal Management‎ , Heatsink-Thermal Interface-Non Bonding‎ , Flex Bonding‎ , Thermal Interface-Damping-Cushioning‎

full list
http://solutions.3m.com/wps/portal/3M/en_US/Electronics_NA/Electronics/Products/Electronics_Product_Catalog/~/Thermally-Conductive-Interface-Tapes?N=8704987
Click to expand...

wow,didn't look at the specs, why is KB sending this shit with their cobs?.....................BUT some do like their eggs fried!:)
 
wietefras

wietefras

Well-Known Member
BM9AGS said:
M reflector designed for a 5.9x3.6" room
So your reference was bogus.
Click to expand...
So just because you cannot read and apparently don't have access to Google the reference is somehow "bogus"? Instead you propose some completely ludicrous test which has zero relevance to the discussion here?

It's exactly the size that I said it was for. Seriously knock it off with this nonsense. And you ALSO get the same PPFD values in a 5x5'tent with a regular reflector. It's not like ypou suddenly lose a huge amount of light if the tent ios slighly bigger. Like I said, the new tent is about uniformity.

Besides it cannot be that hard to understand that a slightly different reflector is going to have much much less impact than not having reflective walls. Talk about bogus.
 
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