New style Samsung LM561C Board

[ganjamystic]

I've been trying to tell people this forever. if you don't believe me, it's easy to test with even a cheapo $25 lux meter.. if you put cobs or boards in a square grid pattern (3x3, 4x4, 5x5, etc..), you will get a hotspot in the center every time.. however, if you leave an empty space in the center, you will find you can achieve almost perfectly uniform coverage...

O...O
O...O

O...O...O
O.........O
O...O...O

O..O...O..O
O.............O
O.............O
O..O...O..O

O..O...O...O..O
O...................O
O...................O
O...................O
O..O...O...O..O

 

[ganjamystic]

the strip guys found the same thing.. if you space parallel strips evenly across a square or rectangular space you will get a hotspot in the center, but if you space them logarithmically, as in closer together toward the edges, farther apart toward the center, you can get nice even coverage..

|.|.|.|.|.|.| = hotspot

||.|..|..|.|| = no hotspot

 

[firsttimeARE]

A "good" PAR meter... there are many meters that are junk

I could be wrong, but even a cheap meter would tell which one is more powerful, no?

If its off its off for both lights

 

[firsttimeARE]

Do any diodes produce 90CRI?

Is there a noticeable difference between 80cri and 90cri, in terms of yield or bud density?

I had heard 90cri sacrifices lumens/watt at the expense of us seeing color better under it. Not sure how true that is. Just what I heard.

 

[see4]

I could be wrong, but even a cheap meter would tell which one is more powerful, no?

If its off its off for both lights

I would agree, as Im far from an expert in color/light clarity. I've seen a [few] videos explaining CRI and TLCI...

for example does a fairly good job of explaining.

I had heard 90cri sacrifices lumens/watt at the expense of us seeing color better under it. Not sure how true that is. Just what I heard.

I remember seeing the same, just not sure where. I'll need to dig around again for that. Though, with The Dawg's grows, the proof seems to be in the pudding.

 

[firsttimeARE]

Proof is always in the pudding

 

[chuckduck]

To answer a few questions. These are 80 CRI and I got the 3500K boards. I started putting the frame together and things were going well to start.


Off to a good start. Decided to put the boards around the outside as a ring as suggested. Driver placement was a little tricky but I think I found a good way to keep things evenly balanced.
Had the boards facing this way just to get an idea of the layout. When I flipped the boards things started to get a little tight and you'll see my problem in the pictures.

Things worked well when the boards were oriented one way but not so well the other. The connectors aren't going to fit. My last post in this forum was called "Watch a moron build a LED light" so this is to be expected. No surprise here. I'm going to walk away from this for the evening and flip some things around in the morning. I still have to wait for cords, connectors and a few other odds and ends. I hope to have everything mounted and wired up tomorrow.

 

[chuckduck]

i would as well, there will be lots of overlap in the center already. or use 9 or throw some cobs in the middle

what is total wattage of this 336 diode board running at full current? thanks

my 304 diode QB gets ~175 watts @ 1400ma 115v so i did (175/304)*336 =193.42 watts - i'm assuming same output and consumption as same diodes - does my logic seem correct?

Maybe someone can double check my math here but the board is 67 volts and I have a 1750mA driver. That works out to 67*1.75= 117.25 per board. That would make the entire light 938 watts if set to run full. So I have a couple options. I can turn it down to work in a 4x4 area. Or I could raise the light to increase the spread to cover a larger area. I'm going to have it in the center of a 4x8 tent.... for now. Just having fun playing around with this.

 

[chuckduck]

If I was to do this again I might use some steel bars or something to firm it up. It's kinda floppy.

 

[nfhiggs]

To answer a few questions. These are 80 CRI and I got the 3500K boards. I started putting the frame together and things were going well to start.
View attachment 4058639

Off to a good start. Decided to put the boards around the outside as a ring as suggested. Driver placement was a little tricky but I think I found a good way to keep things evenly balanced.View attachment 4058640
Had the boards facing this way just to get an idea of the layout. When I flipped the boards things started to get a little tight and you'll see my problem in the pictures.
View attachment 4058641
Things worked well when the boards were oriented one way but not so well the other. The connectors aren't going to fit. My last post in this forum was called "Watch a moron build a LED light" so this is to be expected. No surprise here. I'm going to walk away from this for the evening and flip some things around in the morning. I still have to wait for cords, connectors and a few other odds and ends. I hope to have everything mounted and wired up tomorrow.

Solution to this is simple - attach the boards to the bottom side using Epoxy.

 

[Danielson999]

Square aluminum tubing or even channel. Steel is impractical in that it's super heavy and hard to drill through and it corrodes to the point of rusting whereas aluminum doesn't rust, is super light and you can cut through it with level 1 laser vision.

 

[chuckduck]

Solution to this is simple - attach the boards to the bottom side using Epoxy.

Good idea. Thought I could just set them on top and them slide them around for optimal coverage. I can just screw them to the bottom.

 

[see4]

That is going to be some serious friggin light.
That will definitely be a shades required grow.

 

[see4]

Good idea. Thought I could just set them on top and them slide them around for optimal coverage. I can just screw them to the bottom.

The only concern I'd have with using Epoxy, is it's permanent.

 

[firsttimeARE]

To answer a few questions. These are 80 CRI and I got the 3500K boards. I started putting the frame together and things were going well to start.
View attachment 4058639

Off to a good start. Decided to put the boards around the outside as a ring as suggested. Driver placement was a little tricky but I think I found a good way to keep things evenly balanced.View attachment 4058640
Had the boards facing this way just to get an idea of the layout. When I flipped the boards things started to get a little tight and you'll see my problem in the pictures.
View attachment 4058641
Things worked well when the boards were oriented one way but not so well the other. The connectors aren't going to fit. My last post in this forum was called "Watch a moron build a LED light" so this is to be expected. No surprise here. I'm going to walk away from this for the evening and flip some things around in the morning. I still have to wait for cords, connectors and a few other odds and ends. I hope to have everything mounted and wired up tomorrow.

Where are your heat sinks? They help with the rigidity of the frame. I used 1/16" aluminum angle and channels and came out solid. Also not sure if this helped or not, i believe it did, but I drilled and tapped the structure pieces so they had less wiggle.

Also how arent they going to fit? You know how to wire these? Just use solid core wiring to reach the ballasts

 

[chuckduck]

Where are your heat sinks? They help with the rigidity of the frame. I used 1/16" aluminum angle and channels and came out solid. Also not sure if this helped or not, i believe it did, but I drilled and tapped the structure pieces so they had less wiggle.

Also how arent they going to fit? You know how to wire these? Just use solid core wiring to reach the ballasts

Here's a pic of a previous build.
They are going to fit fine I'm just going to need to fiddle with my placement of a few things. I've made two different 3x3 lights each with four boards so I do have some experience wiring them together.
These boards don't require heat sinks. The LEDs are spaced far enough apart and at the current I'm running it shouldn't be a problem. On my other build the boards max out at about 110F at full power. I am going to document the heat output and have some heat sink ideas if needed. Time will tell. These PCBs seem to be thicker but then again there are more LEDs on it.

 

[nfhiggs]

The only concern I'd have with using Epoxy, is it's permanent.

RTV works well too, as long as its not the quick cure stuff.

 

[Prawn Connery]

Maybe consider mounting your drivers remotely. All my drivers are outside the tent. You need a longer main wire, of course, but it removes a lot of heat and very much simplifies the frame. Also, you don' have to worry about the aluminium being "flimsy", as it's only supporting the weight of the boards.

 

[legalcanada]

View attachment 4058698

Here's a pic of a previous build.
They are going to fit fine I'm just going to need to fiddle with my placement of a few things. I've made two different 3x3 lights each with four boards so I do have some experience wiring them together.
These boards don't require heat sinks. The LEDs are spaced far enough apart and at the current I'm running it shouldn't be a problem. On my other build the boards max out at about 110F at full power. I am going to document the heat output and have some heat sink ideas if needed. Time will tell. These PCBs seem to be thicker but then again there are more LEDs on it.

i would remote drive them, have the drivers mounted on a plywood board or the wall or something. i have a hard time believing no heatsink needed. my quantum boards are 120v @ 1400ma and they run at 75* celsius with heatsink

 

[ganjamystic]

Not my cobs. Crossover par/lumens is less than what is directly under the light source. I use one bare cob per sq/ft evenly spaced, 16x cobs over every 4x4 area of growth, at 12" above the canopy there is no hotspots, just even coverage.

Tested a 4x4 grid of cobs spaced 12" part in a 4x4 tent ... readings at 13"

cool I stand corrected then. if you're running them that close looks like 1 per sq ft is just right to get uniform coverage