DiY LEDs - How to Power Them

[mahiluana]

How many

6 in series / and up to 4 in paralell - 24 chips in total gives you best efficiency,
better heat management and longlife + ~ 50% more light compared to the use of only 6 cobs@1400mA.

If you are able to grow 50% more yield with 50% more light -
your investment of ~ ( $ 360,- for 18 chips) should be compensed after the first grow.

 

[mahiluana]

recommendations

i found good quality here: vanqled.com

 

[Sirtie]

Hello Folks! I hope this is the right place to post this.
I'm looking for some DIYs on how to put together a light with LDD drivers and board (3 or 4 channels) AND a control for sunrise/sunset with Arduino or similar. Could somebody point in the right direction. Thank you!

 

[s20009k]

what drivers do i need for 12 vero29 gen 7 36V (class d)?. looking for around 700-900Watts

 

[GBAUTO]

what drivers do i need for 12 vero29 gen 7 36V (class d)?. looking for around 700-900Watts

I run mine at 2100mA with a HLG-320C-2100B on 4 Vero's/driver so it would take 3 drivers but there are other options. This can give you over 300 watts per driver and allow you to reduce the output via a dimming control.

 

[T-Time]

Hello,

First post here, but I'm long time lurking here and got shiz loads of usefull info without having to as a stupid question yet, so thanks for that

I'm prepering to making my first DIY LED fixture and have a few questions regarding the driver efficiency.
I'll be using 20x CXB3590 3500k DB. Five on a bar, 4 bars total. Driven @1050mA to light up 5x5 space. Witch should give me roughly PPFD of 1220umol averaged and 710W

My two options are:
- 2x HLG-480h-C1400 (A or B to dim ?) 95% efficiency dimmed to 1050mA
- 4x HLG-185h-C1050B 94% eficiency

Will the HLG-480h loose its efficiency while dimmed to 1050mA ?
What potentiometer I need to dimm (externelly)? I know I would need to use 100K ohm + 10k resistor for the HLG-185h. Would it be the same case with 480h ?
While looking into 480h data sheet I've noticed current range is adjustable by A-type via build in potentiometer. Does it mean its either A type adjustable internaly or B type andjusted externaly and I can't get both functions ?
I would like to set it up @1050mA internaly and then adjust the range (10-100%) by external potentiometer.

Thanks
T-Time

 

[sixstring2112]

Hello,

First post here, but I'm long time lurking here and got shiz loads of usefull info without having to as a stupid question yet, so thanks for that

I'm prepering to making my first DIY LED fixture and have a few questions regarding the driver efficiency.
I'll be using 20x CXB3590 3500k DB. Five on a bar, 4 bars total. Driven @1050mA to light up 5x5 space. Witch should give me roughly PPFD of 1220umol averaged and 710W

My two options are:
- 2x HLG-480h-C1400 (A or B to dim ?) 95% efficiency dimmed to 1050mA
- 4x HLG-185h-C1050B 94% eficiency

Will the HLG-480h loose its efficiency while dimmed to 1050mA ?
What potentiometer I need to dimm (externelly)? I know I would need to use 100K ohm + 10k resistor for the HLG-185h. Would it be the same case with 480h ?
While looking into 480h data sheet I've noticed current range is adjustable by A-type via build in potentiometer. Does it mean its either A type adjustable internaly or B type andjusted externaly and I can't get both functions ?
I would like to set it up @1050mA internaly and then adjust the range (10-100%) by external potentiometer.

Thanks
T-Time

i would use the bigger drivers just so you have the extra power if ya want it.i have a bunch of 5 cob fixtures using the smaller drivers and i love them.but they are only good for plants 4 feet or shorter. as far as the dimming questions you lost me a lil.you can have internal dimming and external dimming.its one or the other.you will lose a tiny bit of eff if you dim the 480 to 1050 but not much.the nice thing about the new 480 is dim to off.the bad thing about the new 480 is finding one for less than 150.00 if you can find one at all lol.

 

[NoFucks2Give]

My two options are:

I do not see a 3500K DB in the datasheet. BD? So 72V?

20 CXB x 72V = 1440V
480H-C: 2 x 343= 696V (nine 72V CoBs)
185H-C: 4 x 190 = 760V (ten 72V CoBs)

Coming up short, don't think either option will do the job.

To get 10-100% dimming, B is the only option. A will give you 50-100%. One of the other, not both. Doubt you'd need the 10-50% dimming of the B.
Same potentiometer for both 480 & 185 B types.

Dimming does not affect efficiency. With 110AC you will get 93% @ 50-100% capacity. 230-270AC will get 93-94% @ 60-100% capacity.

How did you calculate your PPFD? At what height? How high will the fixture be over the canopy?

 

[NoFucks2Give]

one for less than 150.00 if you can find one at all lol.

HLG-480H-C1400A $129
HLG-480H-C1400B $138
https://www.trcelectronics.com/ecomm/ProcessItemSearch.aspx?topbarsearchvalue=hlg-480&itemquantity=1
On second page of this search

 

[sixstring2112]

HLG-480H-C1400A $129
HLG-480H-C1400B $138
https://www.trcelectronics.com/ecomm/ProcessItemSearch.aspx?topbarsearchvalue=hlg-480&itemquantity=1

whats the delivery date on those? last i checked it was 6 weeks out

 

[sixstring2112]

I do not see a 3500K DB in the datasheet. BD? So 72V?

20 CXB x 72V = 1440V
480H-C: 2 x 343= 696V (nine 72V CoBs)
185H-C: 4 x 190 = 760V (ten 72V CoBs)

Coming up short, don't think either option will do the job.

To get 10-100% dimming, B is the only option. A will give you 50-100%. One of the other, not both. Doubt you'd need the 10-50% dimming of the B.
Same potentiometer for both 480 & 185 B types.

Dimming does not affect efficiency. With 110AC you will get 93% @ 50-100% capacity. 230-270AC will get 93-94% @ 60-100% capacity.

How did you calculate your PPFD? At what height? How high will the fixture be over the canopy?

db are out there now in 36v data sheets need updated though

 

[NoFucks2Give]

whats the delivery date on those

They have one of each in stock. I have had problems with what their site says vs. actual availability

 

[NoFucks2Give]

now in 36v

Is the 36V a 3.6 Amp?

 

[sixstring2112]

Is the 36V a 3.6 Amp?

3600ma max ? i belive so.its not far off from the 4000k db bins i would imagine. i seen a few people suggest you may see a 3- 5% bump from the cd bin.
i think you can buy them from @REALSTYLES here fairly cheap. rapidled lists cd bin only as far as i can tell.

 

[T-Time]

I do not see a 3500K DB in the datasheet. BD? So 72V?

20 CXB x 72V = 1440V
480H-C: 2 x 343= 696V (nine 72V CoBs)
185H-C: 4 x 190 = 760V (ten 72V CoBs)

Coming up short, don't think either option will do the job.

To get 10-100% dimming, B is the only option. A will give you 50-100%. One of the other, not both. Doubt you'd need the 10-50% dimming of the B.
Same potentiometer for both 480 & 185 B types.

Dimming does not affect efficiency. With 110AC you will get 93% @ 50-100% capacity. 230-270AC will get 93-94% @ 60-100% capacity.

How did you calculate your PPFD? At what height? How high will the fixture be over the canopy?

No, I need DB 36V. No harm going for the top bin
Jerry from kindbrite has them listed. I'll have to send him a message to see are they in stock or is there waiting time on them and the drivers.

B Type it is. I'll need them to be dimmable fairly low as I'll be dimming while watering and working around the plants.

Forward voltage on 480h is 343V so it should fit 10 cobs nicely while running @1050mA and 34V each.

PPFD was calculated from SupraSPL formula found somewhere on RIU:

20 coba * 35.54W = 710.8 dissipation W
710.8 * 0.6122 efficiency = 435 PAR
435 * 0.9 wall losses = 392 PAR W
392 ÷ 1.5m2 = 261 PAR W / m2
261 * 4.64 = PPFD of 1214umol averaged

(EFficiency was taken from CD bin data sheet as I couldn't find any for DB anywhere.)

Probably will be hanging the light 8-12" above the plants. Not sure yet as I'm switching from HID light so I'll be learning to grow with LEDs.

 

[NoFucks2Give]

PPFD was calculated from SupraSPL formula found somewhere on RIU:

Well, it does not work that way. That conversion is wrong.

The 435 PAR is not valid. That would be photon energy in Watts. The 0.6122 efficacy is very efficient and highly unlikely for a phosphor convertor CoB.

A photon has a specific amount of energy associated with its wavelength.

Photon quanta Energy Ep = h•f = h•(c/λ), measured in Watts.
h=6,63•10^-34 [Joule second]; Plancks constant
c=2.998x10^8 [meter/second]; Speed of light
f = [1/s]; Frequency
λ [m] Wavelength in meters

The conversion from lumens to Watts is wavelength dependent as defined by the CIE Photopic Luminous Efficacy table.
I created this table from the CIE table (third column) to show the amount of difference from wavelength to another. http://www.growlightresearch.com/ppfd/lux.html

From the definition of a candela:

The candela is the luminous intensity, in a given direction. of a source that emits monochromatic radiation of frequency 540 x 1012 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian.​

Luminous flux in lumens = Radiant power in watts x 683 lumens/watt x luminous efficacy
Radiant power (watts) = Luminous flux in lumens / (683 lumens/watt x luminous efficacy)


I converted a CoB from lumens to photon energy Watts to PPFD.

http://www.growlightresearch.com/ppfd/convert.html​

The first sets of columns converts 100 lumens at each wavelength to Watts and PPF
The middle set of columns converts 10 µMoles to Watts and Lumens
The third set of column converts a Luxeon CoB from lumens to Watts and PPFD at each wavelength. I measured the Lumens, Watts, and PPFD and compared them to my calculations. So both Measured and Calculated values are there.

Here is a graphic illustration of the converted Luxeon CoB in both Lumens and PPFD.




The luminous flux is the part of the power which is perceived as light by the human eye, and the figure 683 lumens/watt is based upon the sensitivity of the eye at 555 nm, the peak efficiency of the photopic (daylight) vision curve. The luminous efficacy is 1 at the 555nm wavelength .

For example a 470nm photon has an energy of 4.229 x10^-19. which is 0.255 W per µMole, so 1 Watt would be 2.365 x 10^18 photons or 1 Watt Blue @ 470um = 3.926 µMoles
But for a 660nm photon, the energy is 2.723 x 10^-19 Watts which works out to 1 Watt Deep Red @ 660um = 5.513 µMoles

1 Watt Far Red at 730nm = 6.098 µMoles
1 Watt Green at 530nm = 4.344 µMoles

I am going to guess your 4.64 is 1 Watt @ 555nm. So the formulas you used would work for a Lime Green LED which being the most sensitive color with the highest conversion factor in the CIE table, which means your LED is no where near 1214 µMoles, it is a lot less.

But all you have to do is set the height of the fixture closer to the canopy than 1 meter and your µMoles will multiply exponentially.

I have lots of apps that could help you with your fixture. Like finding the ideal position for the LEDs and the height of the fixture.

 

[T-Time]

@NoFucks2Give
Shishhhh... Talking about in depth answers...
Sure. Throw at me whatever calc You've got. I'll try to soak it all in if I can.
I'm only new to this. Started learning about the cobs, photons, wats , efficiency, mA, PAR and everything else only couple months ago. I thought " I've got this" , but then You showed up hahaha

While we're at it I have two more questions.
WAGO 221 connectors are rated to 450V. How's that gonna work If I wan't to connect two HLG-480H together?
Which AWG wire should I use to power them ? 18AWG would be ok or I have to use 12AWG ?

 

[NoFucks2Give]

How's that gonna work If I wan't to connect two HLG-480H together?

Assuming you will not be plugging bare wire into connectors with live lethal voltages, it will not matter.
The only time a connector has any voltage is when it is open.

18 gauge will be fine. It can easily handle 16 Amps. The Molex connector for Bridgelux is 28 gauge.
22 gauge and up will do just fine. 24 would be okay.

The next important step is where to place the LEDs on the bar. You want uniformity. With good uniformity you can place the fixture closer to the canopy.

Knowing where to place the LEDs and at what height to hang the bar is complicated, but after you know, it is simple. For a 5' grow space the bar should be 5' long with 15" between the LEDs. Common logic would say not to place on at each end of the 5 foot space as half of the photons will miss the plants and hit the wall. But it improves the uniformity enough that the bar can be lowered closer to the canopy which greatly increases the flux at the canopy. The height is all about the view angle of the LED.

I use this app to compare two LED view angles. http://www.growlightresearch.com/ppfd/dangles.php (dual angles)

If you space the LEDs at 15" you can put the bar 11" over the canopy. with any other spacing between the LEDs, the bar would have to be higher.

First set of columns is Flux, Times more flux than at max height entered, height of bar, and Interval between LEDs in inches.
The middle section is a PPFD map.
The right end section is min, max, max-min, population variation, population standard deviation, and the last is my 0-100 ranking based on a statistical model.
As the height increases after 11" the variance and standard deviation decreases (improves) , that is only due to the decrease in flux and those statistics improve with smaller numbers.
The white 100 in on the far right indicates my estimated ideal height.

Most put the fixture up fairly high and eye ball the uniformity unless they have a PAR meter. Notice that the uniformity decreases higher than 11".
the flux at 11" is 4.8 times (480%) greater than at 24". Using the Inverse Square, flux at 11" is 12.6 times greater than 1 Meter.

I tested my modeling of uniformity comparing the measured vs. simulation model values and came out with only about 1% of error.

There were about 2 Million calculations done to come up with these numbers.

You can see how the PPFD map changes if you use less (12"-14") than 15" spacing. Because the LEDs will not be mounted at the end of the bar with less than 15" the number on the right will decease.

I'm sure you've seen the "Typical Spacial Distribution" curve in the Cree datasheet, without realizing its importance. Now you know. Optical lenses are not needed with a well designed bar.

 

[T-Time]

Tons of useful info !
Are those calculations done taking led power into consideration ? I wouldn't want to burn my ladies hats off I was thinking to run mine @1050mA

15" spacing on the bar and 20" apart from next bar. Looks like a compromise I'll have to live with as I wouldn't want to go with 25 cobs for a financial reason. unless You propose other set up, like middle bars spaced closer maybe ?

 

[NoFucks2Give]

like middle bars spaced closer maybe

You will not need to purchase additional CoBs. The next topic would be heatsinks. I highly recommend water cooled. I have a water cooled heat sink that is very simple and will cost about $3 per foot plus $30 for tubing and water pumps.

Spacing between bars is a whole different thing. In a straight line I am only calculating two dimensions, photons from the left and right.

I have not finished the calculations for multiple bars, but am far enough along to estimate the distance between two bars. Right now I am in the middle of updating the multi-bar code and cannot run a simulation right now.

UPDATE: I ran a few simulations, and the results look very good. It appears 20" between is going to be fine. A span of 15-20 inches between bars all look good.

In the image below I calculate the flux of each LED at 0.1" increments along the heavy yellow line. This illustration below shows 1 bar of 5 LEDs.

First I calculate the distance from the current point (offset) on the yellow line to each LED using simple right angle trig.
To get the distance I fist need the angle.
angle = arctan(offset/height)
distance = height / cosine(angle)

Then I calculate the flux based on the distance the photons travel and the Inverse Squares Law.
flux = Height Max / (distance x ( radiation distribution flux @ angle))^2

radiation distribution flux @ angle comes from the LED datasheet as shown in the dual angles app:
http://www.growlightresearch.com/ppfd/dangles.php

I you'd like to see a more details on how I calculate the values, I've attached a PDF with draft explanation.
The PDF also explains how I get the radiation distribution angles from the datasheet.





The below illustration show the challenge estimating the distance between between bars, where there are photons coming from forward left, behind left, forward right, and behind right with multiple rows.

The red lines represents a small fraction of the photon paths from the LEDs to the measurement points where I calculate the flux.

Below I measure in 0.1 increments along the vertical yellow line between bars 1 and 2.
I have written the code for two bars. The illustration below show 4 bars of 5 LEDs. So I have an idea about how far apart the bars should be.

Then (I have not written the code yet) measure The yellow line moving the yellow line to the right in 0.1" increments between the blue lines.

To calculate the distance from the offset point to each LED requires an extra trigonometric calculation on the floor.
This is done for every LED on all the bars for each point on the yellow line.

floorAngle = arctan(LED X position/offset)
floorDistance = offset / cosine(floorAngle)
angle =atan(floorDistance /height)
distance = height / (cosine(angle)
flux = Height Max / (distance x ( radiation distribution @ angle))^2

Where offset = each 0.1" along the yellow line.