Minimalistic multichip DIY LED build

[cephalotus]

Also how do we get the right lens for these multi chips?

On eBay, the diameter and the focal length are indicated. But the angles are indicated as a range, like 5-90 deg, or 30-130 deg. 5 deg and 90 deg is a lot of difference, how do we know what we are getting?

Some lenses are adjustable. The eBay store I deal with advertise their lenses in diameter and a single fixed degree.

 

[smoothdog]

Also how do we get the right lens for these multi chips?

On eBay, the diameter and the focal length are indicated. But the angles are indicated as a range, like 5-90 deg, or 30-130 deg. 5 deg and 90 deg is a lot of difference, how do we know what we are getting?

The spread is based on the distance from the led to the lens. The further away it is the tighter the focus. If the lens is not sold with the reflector/base then they advertise the focal range of the lens. If you are looking for a particular angle it is best to buy them as a pair.

 

[mr.wilson]

As you can see in the following picture, multichip lenses create a hot spot in the centre, with noticeably less intensity as you move outward. When picking a lens, you need to calculate the effective coverage rather than the total footprint of the light. The narrower the lens, the more significant the drop off in intensity as you move outward.

 

[Navyblue]

Thanks all for the answers.

Say for a rectangular looking 50W chip, are their dimension standard from different vendor? If so, what is the diameter, focal length and mounting distance to get a 30 deg spread? And how about for a 20W or 10W chip?

 

[TropTrea]

Thanks all for the answers.

Say for a rectangular looking 50W chip, are their dimension standard from different vendor? If so, what is the diameter, focal length and mounting distance to get a 30 deg spread? And how about for a 20W or 10W chip?

The difference in the dimensions of even single emitter 3 watt chips vary considerabley between vendors. Therefore most of them do not have interchangable lenses. Now when you go to multi chips there is even more variences there consider different multichip builders use different brands of single emitters as well as the number of single emitters, and the spacing between them.

Most vendors that offer both will designate which lenses work with there multi or single emmiter chips. I would say your safest bet is to stay with the same vendor for both items if at all possible.

 

[TropTrea]

Also how do we get the right lens for these multi chips?

On eBay, the diameter and the focal length are indicated. But the angles are indicated as a range, like 5-90 deg, or 30-130 deg. 5 deg and 90 deg is a lot of difference, how do we know what we are getting?

This type of lens realy makes the build a little more complex as far as mounting the lens is concerned. The Focal lenght is what is normaly the distance from the center of the lens to the light source. While the diameret of the lens has a lot to do with its actuall effeciency. The good point on lenses like this is that adjusting the distance between the lens and led you can adjust its beam angle. The hard part is calculating this before hand without a considerable knowledge of optics. Therefore the ideal would to have a telescoping tube type of structure that the lens is mounted on and you can therefore adjust the beam angle. Keep in mind though that the longer the distance between the light source and the lens is the more the beam will be concentrated at a smaller angle however the greater the light loss you will also have. Simularly the material and coating on the lens can also effect the quality of light. Often lenses are coated with a UV filtering material that actualy cut off light shorter than a set wave length. Even pure glass has a considerable amount of UV filtering before it is even coated.

 

[mr.wilson]

Typical dome lenses for multichips are made of K9/BK7 borosilicate glass. The light transmission is 96%. From my experience moving the chip an inch or two closer or farther from the lens doesn't change the beam angle dramatically. Adjusting the distance from the water surface to the lens is a more practical method of adjusting the beam angle.

Be careful when using optics narrower than 90˚, as you can burn corals. Use a quantum meter to make sure you are reaching and not exceeding your target intensity.

 

[Navyblue]

Thanks all.

 

[megadeth72]

the 50w-100 chips on ebay all use the same base as far as I can tell, I've ordered from different venders and got the same base. They have 2 plugs on each side for the reflector to lock into. The problem on ebay is the seller does not list what the angle is when the reflector/lens is mounted right to the led.

ac-rc on ebay sells both 90 and 60 degree reflector/lens combo's with the specs so you know what your getting, 26.5mm square opening

I'm not aware of another source anywhere, but I have not looked hard, I'm sure there's a name for the base they all use, dont know what it is

 

[Navyblue]

Thanks, that's very helpful.

 

[megadeth72]

got another multichip via ebay here's how it tests on my diy par meter

Chip has 6500K-7500K 30x and 450nm~455nm 20x and it cost me 27 $

Some par meter results, using a 90 degree reflector/lens

In tank and distance from lens
surface 470par 9.5"
sandbed 300par 18"
corner 175par 18"

top corners 90par 9.5"
dead center 268par 9.5"

24" air results 90par
36" air results 48par

 

[shaima7689]

Hello all!!! I have a 55l (12gallon) tank. I want to keep softies and LPS! And I would like to use LEDs as the sole lighting in my tank. I would like to know which of these two builds is better??:

Build 1: 10w hybrid multi chip (6 450-455 royal blue + 3 20000k) super actinic red phosphor coated LED X 4

Build 2: 20w hybrid multi chip (6 450-455 royal blue + 3 20500k) X 1 + 10w hybrid (as above) X 2

Build 3: 10w hybrid multi chip X 1 + 10k chip + blue chip

Basically the options are these (mixed and matched):

20w Uv chip
20w hybrid (royal blue and 20500k)
20w 14000k
20w 10000k
10w hybrid red phosphor coating (royal blue and 20000k)
10w hybrid (no coating) (royal blue and 20000k)
10w 20000k
10w super actinic
10w 10000k
10 4500k ( warm white)

Everytime I think I have come up with a mix I'm unsure it's sufficient and then I worry so please help!!!

Also I don't want it tooo blue i like some white (sterile look) and I'm making a panel

 

[shaima7689]

Ohh and I'm using an old biscuit tin sanding it down and installing a fan to make the case

 

[mr.wilson]

As much as this is a multichip thread, from time to time questions about 3w arrays and "how should I light my tank" come up. I don't want to go too far off topic, but in the best interest of answering your question, a PAR38 lamp is your best lighting solution for a 55l tank. Even a PAR30 would be enough. You're looking at $30-100 all in and you can have whatever colour combo you want. A 20-24w PAR38 will give you 200 PAR @ 24" with 90˚ lenses.

The only limitation is the PAR series use only one driver so there is no independent control of colour channels. You could use a second PAR30 (9w) for exclusive blue light.

 

[megadeth72]

This is the 10g that runs the 50w mulitchip I posted about in post # 3453

same tank with a rb 50w I was testing

 

[xenia outbreak]

I have spent the last month or so reading this entire thread. What a ride!! It seems to have died off recently, but hopefully there's still a few people around willing to help. I built a simple small multichip fixture for my sump and it works great. Now I want to make something for my display tank 35gal 30"x12"x20"H Here's my plan:

1-350w 36v 9.7a switching power supply

4xLDD-1000H drivers wired in parallel off the power supply---current range: 1000mA, voltage output: 2-52VDC, voltage input: 9-56VDC, pwm dimming

2x30W CW 20000K multichips---1000mA, 30-32V FV 1 per driver

2x10W RB 445nm multichips---1050mA, 10-12V FV wired in series on 1 driver

2x20W RB 453nm multichips---2000mA, 10-12V FV wired in series on 1 driver driven at 1000mA obviously

1-Typhon Boostled controller for dimming, etc..

I saw this idea somewhere on this thread, I just don't remember from who. I have been getting a better grasp of what is possible electrically from reading this thread but I'm still not 100% confident I know what I'm doing. Has anyone done this kind of build with the switching power supply and LDD drivers? Anyone using the Typhon Boostled controller? And is there anything wrong electrically with the way I'm thinking of wiring it? Any feedback is much appreciated. Thanks.

 

[danielcassar]

any suggestions are welcome

any suggestions are welcome

Hi all. It's been months since i posted last.... Lasse suggested me to light my tank with 12 10W LEDS. My tank measurements are as follows length 53" (135cm), 13.5" (34cm) height including sand and depth of 13.5" (34cm). Now I wish some opinions regards how I should place the leds over my tank to avoid disco affects. My plan is to have 6 royal blu leds 455nm and 6 white leds (12,000K) all mounted on a piece of aluminium 46" (117cm) long and 16" wide......please any suggestions are welcome

P.S this is my tank as it is now

Thanks
Daniel

 

[MrShroomy]

I know this thread has died down some but if anyone could help me that would be great. Right now i'm setting up a 90 gallon sps and lps tank. The dimensions are 48" x 18" x 25". I am trying to decide on the best way to make the led fixture. I was thinking 2 pendants, one on each side of the tank, made up of a 50w hybrid and other 20w chips. Earlier in the thread someone mentioned that the larger chips (100w) let a lot of light out on thin tanks (18"). I would rather have fewer chips and fewer drivers. If someone has a better way to do it that would be great. The chips I was looking at are

EPISTAR 50W Super Actinic Blue Hybrid 45mil LED Panel
20 chips 20000K + 30 chips 450-453nm Royal Blue

EPISTAR 20W 10000K Led Panel for Aquarium

EPISTAR 20W 445nm Royal Blue 45mil LED Panel for Aquarium

20W 16000K LED Panel for Aquarium

As far as drivers go I would like to be able to dim them manually but I will most likely not buy a controller. I'm feeling a little overwhelmed with the amount of options and combinations you can have. Any help would be very appreciated thanks!

This is a basic idea of what I would like to do. Feel free to make suggestions!

 

[Skinnysloth]

I know this thread has died down some but if anyone could help me that would be great. Right now i'm setting up a 90 gallon sps and lps tank. The dimensions are 48" x 18" x 25". I am trying to decide on the best way to make the led fixture. I was thinking 2 pendants, one on each side of the tank, made up of a 50w hybrid and other 20w chips. Earlier in the thread someone mentioned that the larger chips (100w) let a lot of light out on thin tanks (18"). I would rather have fewer chips and fewer drivers. If someone has a better way to do it that would be great. The chips I was looking at are

EPISTAR 50W Super Actinic Blue Hybrid 45mil LED Panel
20 chips 20000K + 30 chips 450-453nm Royal Blue

EPISTAR 20W 10000K Led Panel for Aquarium

EPISTAR 20W 445nm Royal Blue 45mil LED Panel for Aquarium

20W 16000K LED Panel for Aquarium

As far as drivers go I would like to be able to dim them manually but I will most likely not buy a controller. I'm feeling a little overwhelmed with the amount of options and combinations you can have. Any help would be very appreciated thanks!

This is a basic idea of what I would like to do. Feel free to make suggestions!

I would add a 20w 420nm led to that cluster to hit the photosynthetic band of chlorophyll A in that region. I wouldn't bother with anything above 10000k as the color accuracy can vary quite a bit.

 

[MrShroomy]

I would add a 20w 420nm led to that cluster to hit the photosynthetic band of chlorophyll A in that region. I wouldn't bother with anything above 10000k as the color accuracy can vary quite a bit.

So i should remove the 20w 16000k? Should i put anything in its place or just have the 50w and three 20w chips. Is there a certain blue to white ratio i should have? I know with the individual 3 w leds there is but I don't know if the same thing applies here.