Kessil 360X Testing
- Thread starter Dana Riddle
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madweazl
2500 Club Member
The light has more than enough spread but you simply cant raise a Kessil more than about 8" and expect PAR numbers adequate to do anything with. 6-8" is ideal for a Kessil. Above that, much of the light spills out of a tank unless it's 24-36" wide and is wasted energy.
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User1
Guest
Makes sense. Thanks. I personally do not own one so was not aware. It seems that the other brands are sometimes mounted higher is why I was asking. That and I assumed (sounds incorrectly) that it would cover more and possibly increase numbers.
Thanks.
madweazl
2500 Club Member
Something like the Radion has considerably less spread and considerably higher output so they're mounted high to get the spread which then reduces the PAR. When they're both used in ideal fashion, the PAR levels and spread become comparable.
Yea, matter of semantics.. Could output 25% more gross photons (or use 25% more watts..
) but due to spreading it out less "net" PAR in one spot..Just lower it an inch or so..
NOTE the colors are not equivalent..
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The Kessil A360we is a great light in regards to the shimmer, color blending, and ease of use. It is definitely not a power house as far as par numbers. The reality is if you are wanting to keep SPS deep in a tank, you wind up needing units spaced every 12 inches apart or supplementing the Kessils with some T5 bulbs. The wide angle lenses wind up giving you very large overlapping areas of light for increased par numbers. For a tank deeper than 24", I think even Kessil would recommend going with a narrow lens version. The wide angle lens is really severe in my opinion, but you don't really have to worry about hot spots with the A360's. I have my kessils mounted very high up in my canopy (like 16"), and I bet the spread is at least 48". I have quite a bit of light spill and loss of par, but I use the kessils mostly to provide some shimmer and to tweak my T5 lighting color. Also, if you need higher par numbers and need to use multiple pucks, the AP700 is probably a better option, as I believe it provides about 2.5x the par of one A360 (of course, it's a little more than double the price).
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Dana Riddle
2500 Club Member
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Dana Riddle
2500 Club Member
Yes, the Tunze I use for water motion was turned off for these tests. As far as further tests, let me check with the owner and see if he's cool with me keeping it a bit longer. And thanks for the compliment!
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Dana Riddle
2500 Club Member
@Daniel Waters response below is right on - couldn't have said it better myself
. Years ago, Sanjay Joshi and I stated in concurrent articles that a PPFD value of 100 was the minimum at the substrate. Can't speak for Sanjay, but my belief was based on data I'd obtained over the years in various tanks (going back to the mid-90's), many of them containing low light-loving corals, such as Bubbles (Plerogyra.) BRS is now recommending a minimum PPFD of around 200 (if my poor memory serves me.) More light is not always better, but this seems reasonable.Hmm. Kessil "logic" looks to be failing at high outputs.. Of course that is just watts not photons..Yes!
In a perfect world the lines should all track together..
Oddly I would have suspected differences in PPFD (different chips, different output at equal wattage) more so than differences in wattage..Of course this is system watts not diode watts..
80 vs 65 vs 50 is a fairly big difference.. To put in in a bit of perspective.. IF all whites and thinking lumens w/ like output chips that's 8000Lumens vs 6500 lumens vs 5000 lumens..
Not sure that is really fair.. but hey food for thought.
BRS "I believe" was referring to SPS dominated tanks (well another generalization) more than "any" tank..
Addendum: TO be fair, it is possible that the blue diodes do produce more photons at a set wattage than the whites sooo it is possible that at lower wattage the REAL output is equal to "whites" at a higher wattage (one would expect some efficiency loss through the phosphors anyways, I guess.
But IF there is a ppfd drop at "blue" significantly below what would be expected for "meter error" then that doesn't apply..
In other words at 50W there could be an equal photon output as at 80W w/ more "whites"..
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naoki
Community Member
Thank you for the wattage info, Dana! I don't want ask too much, but have you ever plotted the wattage (x-axis) vs PPFD/W (y-axis)? For the PPFD, it can be just a point estimate (e.g. 12" in front of the emitters), and it doesn't have to be under the water. Kessil is popular, but they don't release any relevant info (well, in plant grow light market, most respected companies release basic info like total PPF from integrating sphere tests). I'm curious about their driver quality (well, this plot represents other factors like the heatsink efficiency and type of diodes). With lower wattage, LED efficiency increases, but AC/DC conversion efficiency drops. The drop in the driver efficiency could be relatively small with high quality drivers, but below 50% load, the efficiency can be fairly low.
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Dana Riddle
2500 Club Member
I can do that when time permits.
Good point about the color divisions not being equivalent - I should have mentioned that.Yea, matter of semantics.. Could output 25% more gross photons (or use 25% more watts..
Just lower it an inch or so..
NOTE the colors are not equivalent..
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Dana Riddle
2500 Club Member
I can do this for the 360X when time permits and if the owner will extend my time with it. Fluence Bioengineering invited me out to their facility back in April, and said I could bring luminaires to test in their huge integrating sphere. I didn't take advantage, and I'm still kicking myself.
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User1
Guest
If it is the same company I am thinking of I really like how they are laying out their units like the VYPRx. I understand the various form factors, myself included by using a single multi channel, but sometimes I think a bar similar to a florescent tube is more ideal. Then just replicate and add if more light is necessary.
This is a bit off topic, but i wanted to chime in and make some general comments in regards to "Kessil logic", as people often refer to it in lighting posts for Kessil lights. Below is my understanding of Kessil logic. If it or any other information isn't quite right, please let me know!
The idea behind kessil logic is that it allows the user to select a color setting they like and not have to worry about whether the setting is appropriate for coral growth. Kessil controls the spectral light output in such a way that the user can't screw it up so to speak. When LEDs first came out, people / companies were still trying to figure out the best combination of leds to provide the best spectrum for corals in the most efficient way. For the most part, LED fixtures have a really good handle on this now and offer setups that work well. That is why you see very similar set ups / ratios in regards to the types (nm) and quantity of various leds within a fixture across multiple vendors.
So what is actually going on with "kessil logic" with the power to the various leds from Dana's chart above with the wattage? When you have the unit set to the bluer settings, very little power is being driven to the white diodes. When you turn the color up, it increases power to the white diodes also. When you increase the color to the whitest setting (for instance, going from 40% color to 100% color), power to the white leds are increased further and at some point the blue leds are then decreased (which happens around 50% to 60% color setting if i was guessing). This is why the power / wattage drops in Dana's graph showing the whitest setting using LESS watts than the 50% color setting. The 50% color setting is where the unit is maximizing input into each led chip. That's the "logic" that is going on. I can tell you as a lay person who had never used LED lights many years ago, this simplicity was nice and appreciated. Turn a knob to intensity and to the color you like and forget about it.
As far as par, the reality is that the kessil light could probably put out more par by allowing the blue diodes to stay maxed while the white diodes are increased. But i think Kessil's goal was to create a light that was "idiot proof" so people would be less able to fry corals (which might also explain the 140 degree wide angle lens choice, so there's less hot spots). Of course, there might also be technical / design reasons behind the way the kessil logic works, such as trying to limit too much heat if all diodes were allowed to run at maximum for instance.
Lastly, as i believe most people are aware nowadays, not all photons are are as useful as others to corals. A photon emitted in the 550 nm range may measure the same as a photon in the 450 nm range on a par meter, but we know the 450 nm will be better utilized by corals. Kessil tries to steer the conversation away from par to focus on this fact. Nowadays, though, I feel like almost all major LED fixtures have a good handle on their led chip / nm offerings, so i think par can be a very useful tool. The areas, though, we don't really see discussed as much but are probably just as important are things such as the quality of the actual led chip being used, effective cooling designs, and how leds are being driven. These are things that are harder to quantify but will most likely affect the long term performance of a unit.
Sorry if this was too iff topic!
I will say after seeing this thread that I'm not that inclined to upgrade my Kessils A360we to the x version anytime soon. But maybe i need to see one in person!
The idea behind kessil logic is that it allows the user to select a color setting they like and not have to worry about whether the setting is appropriate for coral growth. Kessil controls the spectral light output in such a way that the user can't screw it up so to speak. When LEDs first came out, people / companies were still trying to figure out the best combination of leds to provide the best spectrum for corals in the most efficient way. For the most part, LED fixtures have a really good handle on this now and offer setups that work well. That is why you see very similar set ups / ratios in regards to the types (nm) and quantity of various leds within a fixture across multiple vendors.
So what is actually going on with "kessil logic" with the power to the various leds from Dana's chart above with the wattage? When you have the unit set to the bluer settings, very little power is being driven to the white diodes. When you turn the color up, it increases power to the white diodes also. When you increase the color to the whitest setting (for instance, going from 40% color to 100% color), power to the white leds are increased further and at some point the blue leds are then decreased (which happens around 50% to 60% color setting if i was guessing). This is why the power / wattage drops in Dana's graph showing the whitest setting using LESS watts than the 50% color setting. The 50% color setting is where the unit is maximizing input into each led chip. That's the "logic" that is going on. I can tell you as a lay person who had never used LED lights many years ago, this simplicity was nice and appreciated. Turn a knob to intensity and to the color you like and forget about it.
As far as par, the reality is that the kessil light could probably put out more par by allowing the blue diodes to stay maxed while the white diodes are increased. But i think Kessil's goal was to create a light that was "idiot proof" so people would be less able to fry corals (which might also explain the 140 degree wide angle lens choice, so there's less hot spots). Of course, there might also be technical / design reasons behind the way the kessil logic works, such as trying to limit too much heat if all diodes were allowed to run at maximum for instance.
Lastly, as i believe most people are aware nowadays, not all photons are are as useful as others to corals. A photon emitted in the 550 nm range may measure the same as a photon in the 450 nm range on a par meter, but we know the 450 nm will be better utilized by corals. Kessil tries to steer the conversation away from par to focus on this fact. Nowadays, though, I feel like almost all major LED fixtures have a good handle on their led chip / nm offerings, so i think par can be a very useful tool. The areas, though, we don't really see discussed as much but are probably just as important are things such as the quality of the actual led chip being used, effective cooling designs, and how leds are being driven. These are things that are harder to quantify but will most likely affect the long term performance of a unit.
Sorry if this was too iff topic!
I will say after seeing this thread that I'm not that inclined to upgrade my Kessils A360we to the x version anytime soon. But maybe i need to see one in person!
