LEDBrick Project - DIY pendant w/ pucks

[theatrus]

After poking around with version one of the design, I noticed a lot of air recirculation within the case. Enter, the fan shroud:

I also redesigned the intake to be 100% from the top of the unit and not the sides, and made some artistic upgrades which give it a bit more style over yet another box with holes in it:

Also, the firmware is updated (finally) to read the on-LED-board MCP9808 temperature sensor.

 

[theatrus]

The family grows and undergoes some new firmware feature testing, including temperature based fan spin-down.

 

[Poseidon]

Wonderful!

For the top of the brick, I think a cover would add to the overall appearance, of course there would need to be holes for the airflow. If you made a cover, you could then attach a center mounting point for your cable hanging kit, or even use a small diameter steel cable ran parallel to your incoming power lines and have the appearance of a single small cable coming into the top of the box.

I really like the use of closely spaced LED's, I have been considering going to a puck based LED unit to replace my Phoenix 14K for a couple of years now.

 

[theatrus]

Wonderful!

For the top of the brick, I think a cover would add to the overall appearance, of course there would need to be holes for the airflow. If you made a cover, you could then attach a center mounting point for your cable hanging kit, or even use a small diameter steel cable ran parallel to your incoming power lines and have the appearance of a single small cable coming into the top of the box.

I really like the use of closely spaced LED's, I have been considering going to a puck based LED unit to replace my Phoenix 14K for a couple of years now.

Agree on the cover totally. I need to replace my fan header with a right angle one since right now it's above the case - oops.

In this scenario I'm mounting these on an aluminum rod slid under the cross cables which is held on hooks at the top of my canopy. For an open top look I'd totally do a single cable solution. Would need to look at the proper structural support - right now the case is effectively non old bearing and everything is held by the M4 stainless rods.

I'll post pictures of them mounted soon.

As for spacing, I'd consider increasing the area density on the next revision, or even consider a Vero multichip in the center.

 

[McPuff]

This is really cool. I'm always amazed at what some people on this board can accomplish!!

 

[theatrus]

I've been running an extended burn-in in the garage where I cycle Bluetooth messages at all four units every 100ms with different power levels. Some tweaking of the existing Go based gatt module was needed, and its not a full control system yet but does the job.

The units hanging off a rod in the garage:

Controller code (sans gatt changes):

https://github.com/theatrus/ledbrick/blob/master/controller/ble/ble.go

 

[Fish4ead]

OK. Who are you? I've done some simple coding myself. Robots, cars, simple lighting controls. But your coding is way above my level. What do you do for a living? Where did you learn all of this?

 

[theatrus]

OK. Who are you? I've done some simple coding myself. Robots, cars, simple lighting controls. But your coding is way above my level. What do you do for a living? Where did you learn all of this?

If you really want to know, click through github to other links.

Software engineer by trade. Did many years of embedded, now doing backend servers for a living at various companies you may have heard of.

 

[ReefWreak]

OK. Who are you? I've done some simple coding myself. Robots, cars, simple lighting controls. But your coding is way above my level. What do you do for a living? Where did you learn all of this?

He literally puts his name on the PCBs, and google takes all of 0.52 seconds to return 157,000 results, of which the top ones coincide very closely with the project at hand. lol.

Super cool project so far, really great professional-level results. With time and scale Ecotech/AI could have some serious competition on their hands!

 

[Poseidon]

Not that it matters much, but how much does each of those bricks weigh? Would you think that 4 of them would cover a 24x24 footprint well?

I'm thinking of a similar project, but using the old "sun lifts" to move the lights out of the way as needed.

 

[theatrus]

The heat sink is chunky, so each one is somewhere just south of two pounds. I haven't weighed it fully assembled.

 

[Fish4ead]

He literally puts his name on the PCBs, and google takes all of 0.52 seconds to return 157,000 results, of which the top ones coincide very closely with the project at hand. lol.

Super cool project so far, really great professional-level results. With time and scale Ecotech/AI could have some serious competition on their hands!

I didn't literally mean "who are you" but thanks for the sarcasm and attitude, it really helps.

 

[theatrus]

4 T5s out, 4 LEDBricks in.

Controller on a remotely located RaspberryPi is ticking away:

 

[n0rk]

For me, this is pretty much the essence of DIY and why it's satisfying. Absolutely awesome project, I can't wait to see it progress now they're installed!

 

[theatrus]

For me, this is pretty much the essence of DIY and why it's satisfying. Absolutely awesome project, I can't wait to see it progress now they're installed!

Thanks! So far the controller has been in sync with the lights continuously since Saturday. Crossed fingers!

I had to tear out my old Monti cap tower due to mechanical breakage at the bottom. It was pretty ungainly to remove a sand to out-of-water stack of it, mostly dead skeleton due to shading. Upside is I have a whole 1/3rd of my tank back to grow new things [emoji1360]

 

[Fish4ead]

For me, this is pretty much the essence of DIY and why it's satisfying. Absolutely awesome project, I can't wait to see it progress now they're installed!

Agreed, I can't thank you enough for not only sharing your project but the detail you provided us.

 

[theatrus]

Thanks!

While these units are done for now, I am building a few more drivers and lights which may be more universally applicable.

One shortcoming of this design is the maximum PWM frequency of the PCA9685 is 1.5kHz, which is absurdly low. For the 500kHz switch speed I would ideally want a 50kHz PWM. You can see the low frequency on a suitably fast phone camera if it's running at high speed. A lot of drivers also have current programmability, without having to adjust shunts.

The next driver series under development has an I2C device onboard (a super cheap basic MCU) which will be able to run several PWM channels and program the maximum current in 32-64 steps. The I2C can be chained to several driver boards which means your main controller wiring becomes much easier (2 wires + ground, shared) and let's you use nearly anything for a main controller (since the smarts are all on the driver board, no PWM needed. Great for Raspberry Pis). I need a good name for the drivers (not that LEDBrick was good) - SmartAcro? [emoji854]

 

[theatrus]

I did some exploratory work on a new fixture for a frag tank, or as a nano pendant. The original is still running fine.

This time I'm looking at using reflectors with a combination of a Vero or other COB for white and discrete emitters for the other spectral portions.

I'm starting with a Ledil Brooke series reflector, which is expensive in ones and twos (like, $6!), but can probably subbed out for something less crazy.

Ledil Brooke - look for the BXRA ES footprint in 50degree

Some pictures of a sample unit on 2" and 3.5" heatsinkusa stock. I'd probably get the round stock if I did a single unit version:

I can fit a variety of LEDs in the space for the emitter - in this case 9 total, 2x Rebel, 4x Oslon Squre, 3x Cree XP/XT footprints:

(inner circle is the board-side of the reflector, outer circle is the full diameter)

Thermals will of course be critical with that many close packed heat sources. I can easily slam in 2 or so of the (very expensive) Rebel UV emitters.

With some informal testing with this reflector, it has nowhere near the hotspot problem a classic lens makes - anything in the cone of light has a relatively even illumination (using a Vero 10 as the guinea pig, even though this wide one isn't designed for it).

I'm also working on a new (I2C controlled, analog and digital / PWM dimming for maximum control) boost+buck driver in a 2 or 3-up configuration which may interest a number of people. Run up to 50V out from 12-36V inputs, at 1.5-2A.

 

[theatrus]

I may have found a good compromise for puck wiring.

Since the Aluminum core boards are all single layer, through-hole terminal blocks are out. I used a Molex PicoLock connector on my previous puck, and its great, except that its a lot of work to hand build cables and requires at the very minimum a special crimp tool.

Phoenix and AVX both make SMT terminal blocks which are low profile and feature a push-release mechanism:

https://www.phoenixcontact.com/online/portal/us?urile=pxc-oc-itemdetail:pid=1702474

 

[theatrus]

Did some more iteration on this concept. This is a 2in diameter circle MPCB, with an overhang. This should fit nicely on the round PCB from HeatsinkUSA, which would make a perfect little DIY pendant for small tanks or anywhere else a hanging pendant is ideal.

The footprints are arranged as two channels, with:

1x Rebel, 5x Osram Square (for the 5W Royal Blue LEDs)
4x Cree XP/XT + 1x Rebel

Dropping in different/new footprints is trivial at this point - what would interest people? More Rebel? All Cree? Luxeon Z? I'm looking for a raw-chip source of violets which isn't going to break the bank. I'm also trying some new branding not under the LEDBrick name