[minorhero]

Hello folks!

I am in the midst of building a large vivarium and I am in need of advice on making a custom light for this critter. The vivarium is 4 feet long, 3 feet tall, and 20 inches wide. The opening for the light is 8 inches wide and about 40 inches long.

I want a light that will hit as high up the back wall as possible while also providing at least 50 ppfd (more preferred) at 36" inches. I am guessing this will be a combination of COBs and PCB LEDs. I learned a lot from the last time I built a light, and one important lesson is that colored lights on a vivarium are a bad idea. I was really excited to have richer then real colors on my last vivarium, and when the top is dry it does look lovely. BUT when I mist (which happens every day) either water gets on the top glass or condensation forms. This wouldn't matter except that these water droplets create a lensing effect from the LEDs. For the white leds this doesn't matter. But for the red and cyan leds it means I get little red or cyan spotlights in the tank which is super weird looking.

Not something I would have thought about but having experienced it, I now know to avoid it. So this light needs high cri but only using white light, no RGB colors.

Thoughts on which components to use?

 

[jeffkrol]

Hello folks!

I am in the midst of building a large vivarium and I am in need of advice on making a custom light for this critter. The vivarium is 4 feet long, 3 feet tall, and 20 inches wide. The opening for the light is 8 inches wide and about 40 inches long.

I want a light that will hit as high up the back wall as possible while also providing at least 50 ppfd (more preferred) at 36" inches. I am guessing this will be a combination of COBs and PCB LEDs. I learned a lot from the last time I built a light, and one important lesson is that colored lights on a vivarium are a bad idea.

Still have the height restriction?

I was really excited to have richer then real colors on my last vivarium, and when the top is dry it does look lovely. BUT when I mist (which happens every day) either water gets on the top glass or condensation forms.

This wouldn't matter except that these water droplets create a lensing effect from the LEDs. For the white leds this doesn't matter. But for the red and cyan leds it means I get little red or cyan spotlights in the tank which is super weird looking.

Yea that does happen. W/ the light higher up it's a bit less of an issue.

Not something I would have thought about but having experienced it, I now know to avoid it. So this light needs high cri but only using white light, no RGB colors.

Thoughts on which components to use?

Initial thought was Bridgelux EB strips but at 40" they don't fit quite as nicely as they should.


Bridgelux Decor COB's and Lumileds Crisp White should be enough..
https://www.bridgelux.com/sites/def... EB Series Gen2 Data Sheet 20171020 Rev A.pdf

https://www.lumileds.com/products/cob-leds/luxeon-cob-with-crispwhite/


Red,cyan.violet will be well covered and intensity w/ enough COB's.
Issue will be driving a large array w/out being a logistical mess..


Alternate and I believe a bit higher CRI in combination is the fresh fish and crisp white..
The bridgelux has an advantage w/ added "regular blue" diodes though.
FF/CW

Using the new metrics for color fidelity the FF/CW:
100/100 would be perfect light though one needs to understand few actually prefer complete fidelity w/ nature.


Rf =93 (fidelity to standard)

Rg=101 (gamut >100 more saturated colors)

CCT 5116
CRI 96.5
PPF total 184.82

http://www.qualiteitems.com/images/2freshfish1crispwhite.csv


6 (4/2) COB's would be 21000 Lumens.. 369 PPF to play with.
Note ppf is an area-less measurement..

Alternate..
2 packs staggered..
https://store.yujiintl.com/collecti...ds-high-cri-95-mcpcb-30w-led-module-pack-5pcs

2900 lumens each at 1050mA current..

 

[minorhero]

Still have the height restriction?


Yea that does happen. W/ the light higher up it's a bit less of an issue.


Initial thought was Bridgelux EB strips but at 40" they don't fit quite as nicely as they should.


Bridgelux Decor COB's and Lumileds Crisp White should be enough..
https://www.bridgelux.com/sites/def... EB Series Gen2 Data Sheet 20171020 Rev A.pdf

https://www.lumileds.com/products/cob-leds/luxeon-cob-with-crispwhite/


Red,cyan.violet will be well covered and intensity w/ enough COB's.
Issue will be driving a large array w/out being a logistical mess..


Alternate and I believe a bit higher CRI in combination is the fresh fish and crisp white..
The bridgelux has an advantage w/ added "regular blue" diodes though.
FF/CW

Using the new metrics for color fidelity the FF/CW:
100/100 would be perfect light though one needs to understand few actually prefer complete fidelity w/ nature.


Rf =93 (fidelity to standard)

Rg=101 (gamut >100 more saturated colors)

CCT 5116
CRI 96.5
PPF total 184.82

http://www.qualiteitems.com/images/2freshfish1crispwhite.csv


6 (4/2) COB's would be 21000 Lumens.. 369 PPF to play with.
Note ppf is an area-less measurement..

Alternate..
2 packs staggered..
https://store.yujiintl.com/collecti...ds-high-cri-95-mcpcb-30w-led-module-pack-5pcs

2900 lumens each at 1050mA current..

Probably prefer not to have the yuji option. I would like to keep the lights within 6 inches of the top of the tank if that makes a difference. It seems you are suggesting either bridgelux or fresh fish? So much of this is greek to me. Which would you suggest going forward with?

 

[jeffkrol]

Probably prefer not to have the yuji option. I would like to keep the lights within 6 inches of the top of the tank if that makes a difference. It seems you are suggesting either bridgelux or fresh fish? So much of this is greek to me. Which would you suggest going forward with?

Think it wouldn't make much difference. Bridgelux are def cheaper.. Still would add the crisp white COB's as well though..

One other alternative and can run at constant voltage of 24V soo no messing with drivers.
Fortunately 1ft lengths so easier to tweak w/ 40"

https://store.waveformlighting.com/...9-cri-led-linear-module?variant=8190565777510
$379 for 9 total, 2 rows 6500k 1 row 5000k.. 75.6W and 7200 lumens
No warm option atm though..

Crisp white & fresh fish 8:3 ($73.89/3 39,846 Lumens $220.69 plus $7 x 11 for LDD's..$297.69
ff $18.35 each

Using Brigelux instead
$6.42 or $12.15 each V13 or v18
$130.17 from digikey for 8:3 chips..

About a $90 difference and actually more potential light..
$220 vs $130 for the COB's

4737 x 8 + 1006 x 3 =40914 lumens

did this fast so consider it tentative..
Bridgelux gamut number is "slightly" below 100 but the crisp white should boost the red/violet saturation a bit.

Roughly 300Watts..

 

[minorhero]

Think it wouldn't make much difference. Bridgelux are def cheaper.. Still would add the crisp white COB's as well though..

...

About a $90 difference and actually more potential light..
$220 vs $130 for the COB's

4737 x 8 + 1006 x 3 =40914 lumens

did this fast so consider it tentative..
Bridgelux gamut number is "slightly" below 100 but the crisp white should boost the red/violet saturation a bit.

Roughly 300Watts..

Well if its cheaper and more powerful I can't help but feel that brigelux is the way to go. How would this look? 8 brigelux COBs plus 3.. other COBs? Go with the Led Supply heatsink again? Or something bigger? I measured the hole in my top last night and its 44" long x 8 inches wide. So a little more length to work with if needed.

Definitely not concerned with sunrise or sunset options on this build. The lights will go on at 8am and go off at 8pm and the room the tank is in is above ground with a good number of windows. So even if my family was not up and about one particular morning the room itself will get natural light for the actual sunrise and sunset.

 

[jeffkrol]

Crisp white is to add violet and more red.
Sunrise/set would just be a perk.The Bridgelux royal blue and regular blue is also a bonus

It's also to balance the coolness of the 6500 k
Any lower k cob will do.

You stated you wanted to shy away from any colors .


Any pairing of cw/ww cobs will be similar.

As to the heat sink dealing w/300w is out of my err "expertise" so I'd recommend adding a fan or 2 for insurance

These recommendations are based on quality and quantity if light.
Cheaper cobs are fine

Keep in mind this is a one row affair.
If needed adding a string or 2 if cheap white emitters is cheap.. 12 plus a driver is under
$20 though it "only" adds 24W.

Keep expansion in mind when sizing the power supply..

https://www.neherpetoculture.com/vivariumlighting101

For general info

ESTIMATE of PPFD at 90cm..

* MIXING LIST
----------------------------------------
myData luxcrispwhite1203.csv [120°] x3
myData bridgeluxv6500.txt [120°] x8
----------------------------------------

* SIMULATION DATA
----------------------------------------
Luminous flux : 25,283 lm
Radiant flux : 94,939 mW
PPF : 419 umol/s
TCP : 5680 K
CRI : 93
λp : 472 nm
Color : #FFE9D5
----------------------------------------

* PERFORMANCE @ 90cm
----------------------------------------
Irradiance : 12.4 W/m²/s
Illuminance : 3,311 lx
PPFD : 55 umol/m²/s
----------------------------------------

by SPECTRA 1.0β @ 1.023world
http://spectra.1023world.net/

Used 1000 Lumens for crisp white (COB 1203)and 2782 for Bridgelux 6500k approx.
Prev calcs used the larger COBs 3x larger in output.

BXRE-65S4001-C-7x
L2C5-30901208E15C0

 

[jeffkrol]

Sorry realized I referenced some BIG Crisp white COB's which ar over $30 each..
just use the smaller ones at 1500 Lumens.

BXRE-65S4001-C-74‎
34V @ 1A 4700 lumens 80ppf

L2C5-30901204E13C0‎
35.3V @ 450mA 1579 lumens

@ 1A 2700 lumens 37.3V
(4700 x 8) + (2700 x 3) = 45,700 Lumens

Corrected data:
* MIXING LIST
----------------------------------------
myData luxcrispwhite1203.csv [120°] x6
myData bridgeluxv6500.txt [120°] x13
----------------------------------------

* SIMULATION DATA
----------------------------------------
Luminous flux : 42,220 lm
Radiant flux : 158,452 mW
PPF : 700 umol/s
TCP : 5560 K
CRI : 92
λp : 472 nm
Color : #FFE5D0
----------------------------------------

* PERFORMANCE @ 90cm
----------------------------------------
Irradiance : 20.8 W/m²/s
Illuminance : 5,530 lx
PPFD : 91.8 umol/m²/s
----------------------------------------

by SPECTRA 1.0β @ 1.023world
SPECTRA

 

[minorhero]

Sorry realized I referenced some BIG Crisp white COB's which ar over $30 each..
just use the smaller ones at 1500 Lumens.

BXRE-65S4001-C-74‎
34V @ 1A 4700 lumens 80ppf

L2C5-30901204E13C0‎
35.3V @ 450mA 1579 lumens

@ 1A 2700 lumens 37.3V
(4700 x 8) + (2700 x 3) = 45,700 Lumens

Corrected data:
* MIXING LIST
----------------------------------------
myData luxcrispwhite1203.csv [120°] x6
myData bridgeluxv6500.txt [120°] x13
----------------------------------------

* SIMULATION DATA
----------------------------------------
Luminous flux : 42,220 lm
Radiant flux : 158,452 mW
PPF : 700 umol/s
TCP : 5560 K
CRI : 92
λp : 472 nm
Color : #FFE5D0
----------------------------------------

* PERFORMANCE @ 90cm
----------------------------------------
Irradiance : 20.8 W/m²/s
Illuminance : 5,530 lx
PPFD : 91.8 umol/m²/s
----------------------------------------

by SPECTRA 1.0β @ 1.023world
SPECTRA

This is exactly what I needed!

This is also going to sock me right in the wallet pretty hard heh. Given that this will be made up of 11 COBs I am guessing I just put a straight line down the middle of the heatsink. Pricing out heatsinks it looks like just the bar will be around 100 dollars. I figure by the time I throw in fans, incidentals plus the power supply I am looking at 400 dollars. Gosh darn lights are expensive! I also don't think I can accomplish what I want without spending the money though.

 

[minorhero]

BXRE-65S4001-C-74‎
34V @ 1A 4700 lumens 80ppf

L2C5-30901204E13C0‎
35.3V @ 450mA 1579 lumens

@ 1A 2700 lumens 37.3V
(4700 x 8) + (2700 x 3) = 45,700 Lumens

Getting ready to place the order, is this the right size/kind of power supply?

 

[jeffkrol]

Nice but fancier than it needs to be.

https://www.ledsupply.com/power-supplies/mean-well-lrs-enclosed

LRS-350-48

Take est. Voltage x driver current to get watts/cob.
Add them up and add 10%

If your going to run all at 1A est would be like 38w x 11= say 450w (w/fudge factor)

Both would be too small though the 350 is closer.

If you drop drivers to 700mA things work out better.

Roughly under 300W then

THIS is better all around.

Se-440-48 at digikey.
https://www.digikey.com/product-detail/en/mean-well-usa-inc/SE-450-48/1866-4477-ND/7706611

(8 x 34 x 1) + ( 3 x 37.3 x 1) x 1.1 = 395.9

watts

It is possible to get the 36v version and dial up the voltage to 39.6 v .
But prob reduce the drive current in the 3 Cobs to guarantee.

Only reason to consider this is a tiny gain in is efficiency.
At least as I understand this.

That 100w costs you $40...

 

[minorhero]

Nice but fancier than it needs to be.

https://www.ledsupply.com/power-supplies/mean-well-lrs-enclosed

LRS-350-48

Take est. Voltage x driver current to get watts/cob.
Add them up and add 10%

If your going to run all at 1A est would be like 38w x 11= say 450w (w/fudge factor)

Both would be too small though the 350 is closer.

If you drop drivers to 700mA things work out better.

Roughly under 300W then

THIS is better all around.

Se-440-48 at digikey.
https://www.digikey.com/product-detail/en/mean-well-usa-inc/SE-450-48/1866-4477-ND/7706611

(8 x 34 x 1) + ( 3 x 37.3 x 1) x 1.1 = 395.9

watts

It is possible to get the 36v version and dial up the voltage to 39.6 v .
But prob reduce the drive current in the 3 Cobs to guarantee.

Only reason to consider this is a tiny gain in is efficiency.
At least as I understand this.

That 100w costs you $40...

So I'm afraid you are going to have to talk to me like I am a child when it comes to this stuff. It sounds like you are saying I should buy this power supply: https://www.digikey.com/product-detail/en/mean-well-usa-inc/SE-450-48/1866-4477-ND/7706611 and buy 2 different drivers? 3 at 700 and 8 at 1000 with the 700s on the lumileds? I know how to repeat what I did for the previous light I built, but that is literally as far as my knowledge goes, so if I need to do other things then solder drivers to COBs etc I'm going to need you to walk me through it ;P

If there is a cheaper option where the quality of the colors is just as good I'm all for it. I can go a little down on the strength of light if needed, I would just like to hit 50 ppfd at substrate as the minimum. If its 60 or 90 ppfd is not as important as it would be to have nice colors if that makes sense.

 

[jeffkrol]

Simple answer no matter what drivers you choose =/< 1A each that BIG power supply will be fine..
https://www.digikey.com/product-detail/en/mean-well-usa-inc/SE-450-48/1866-4477-ND/7706611
450Watt capable
If you want to save a few dollars and lose some wattage the smaller power supply and all 700mA drivers fine
PART #: LRS-350-48
https://www.ledsupply.com/power-supplies/mean-well-lrs-enclosed

The last option is to use 700mA drivers fro the warm whites, 1A drivers for the cool white COBs
and go w/ a SE-450-36 but would most likely need to TWEAK the voltage adjustment on the power supply
so would need a VOM preferrable, or "dial it up" to pot max.
Generally the closer a pwer supply output matches it's "running voltage" the more efficient it is.
Best to ignore this option till you get a better grasp on how I arrived at it.
It's not difficult but one needs to pay more attention to details and frankly reality i.e actual testing things.


Again SE-450-48 works for any of the above but costs sig. more than the LRS series.
It does give "some" room for more COBs down the road though.




Easiest way to calculate all this is just add up the driver currents i.e 11 x 1 =11A
And take the COB (or series string added voltages) add 4 and that gets you the minumum voltage needed
Say 36V + 4 =40V minimum rating. The DRIVER will VARY the voltage to meet it's Amp setpoint.

Problem is this guess is usually expensive since you rarely run a COB at the voltage used to create the estimate.
See using that type of guess would mean you'd want a 48v 11A power supply.
WAY bigger than reality..

Only things one needs to know
W = V X A
voltage adds in series
The voltage (potential across the diode) of a led is determined by it's current and vis versa (some people won't like this description)
current divides in parallel.

 

[minorhero]

Simple answer no matter what drivers you choose =/< 1A each that BIG power supply will be fine..
https://www.digikey.com/product-detail/en/mean-well-usa-inc/SE-450-48/1866-4477-ND/7706611
450Watt capable
If you want to save a few dollars and lose some wattage the smaller power supply and all 700mA drivers fine
PART #: LRS-350-48
https://www.ledsupply.com/power-supplies/mean-well-lrs-enclosed

The last option is to use 700mA drivers fro the warm whites, 1A drivers for the cool white COBs
and go w/ a SE-450-36 but would most likely need to TWEAK the voltage adjustment on the power supply
so would need a VOM preferrable, or "dial it up" to pot max.
Generally the closer a pwer supply output matches it's "running voltage" the more efficient it is.
Best to ignore this option till you get a better grasp on how I arrived at it.
It's not difficult but one needs to pay more attention to details and frankly reality i.e actual testing things.


Again SE-450-48 works for any of the above but costs sig. more than the LRS series.
It does give "some" room for more COBs down the road though.




Easiest way to calculate all this is just add up the driver currents i.e 11 x 1 =11A
And take the COB (or series string added voltages) add 4 and that gets you the minumum voltage needed
Say 36V + 4 =40V minimum rating. The DRIVER will VARY the voltage to meet it's Amp setpoint.

Problem is this guess is usually expensive since you rarely run a COB at the voltage used to create the estimate.
See using that type of guess would mean you'd want a 48v 11A power supply.
WAY bigger than reality..

Only things one needs to know
W = V X A
voltage adds in series
The voltage (potential across the diode) of a led is determined by it's current and vis versa (some people won't like this description)
current divides in parallel.

Ok getting slightly better at understanding

I am about to pull the trigger then as I think I have what I need but just to be sure, does this look correct?

The cost savings between the two power supplies is 35 dollars before shipping is taken into consideration and less once it is. I don't mind paying a bit more for the simplicity of ordering from the same location when the difference is not much. Similarly there appears no cost difference between the 1A drivers and the 700ma so I will keep the 1A.

 

[jeffkrol]

Ok getting slightly better at understanding

I am about to pull the trigger then as I think I have what I need but just to be sure, does this look correct?

The cost savings between the two power supplies is 35 dollars before shipping is taken into consideration and less once it is. I don't mind paying a bit more for the simplicity of ordering from the same location when the difference is not much. Similarly there appears no cost difference between the 1A drivers and the 700ma so I will keep the 1A.

Crisp white really shouldn't be run at 1A..700mA will be better for longevity.

Rest is fine...

 

[minorhero]

Crisp white really shouldn't be run at 1A..700mA will be better for longevity.

Rest is fine...

Thank you! Much appreciated! I bought three 700ma and eight 1a drivers and the rest as listed. Had to buy from both mouser and digikey actually since neither had everything needed in stock.

I also bought 4 usb powered cooling fans for the heatsink. So hopefully sometime next week I will have all the parts in and can begin assembly.

 

[jeffkrol]

Yay.

Yea I peeked at Mouser to see if you could get all in one place but no luck.

 

[minorhero]

Build complete!! Also wow need to dim this sucker

I used thermal adhesive to attach the cobs to the heatsink and drilled holes for wires to be run through from the finned side to keep the business side of the heatsink as clean as possible:

After that I wired up the drivers:

I put it on the viv and turned it on the results.. exceeded expectations by a LOT:

After owning frogs for a bit in my other tank I discovered that they don't much like super bright lights so.... yeah going to need to dim this sucker down a bit. There is a a screw like knob on the power supply, can I simply turn that to dim the light? Or do I need to install something else? Or are these COBs not dimmable and I should find something translucent to put on the tank to diffuse more of the light?

 

[jeffkrol]

Short of removing cobs you'll need to dim it on the ldd 5v pwm side


.https://www.google.com/amp/s/www.pl...how-use-tc-420-control-ldd-drivers.html?amp=1

 

[jeffkrol]

Oh yea you can also dim it bt applying 0 - 2.4 volts on the dim wire.

 

[minorhero]

Oh yea you can also dim it bt applying 0 - 2.4 volts on the dim wire.

This sounds intriguing, how do I make that happen? Can I buy some kind of twisty knob like device and hook that up to the power supply on one side and on the other side hook it up to the dimming wire (the white one on the drivers right?).