[MrMan]

So I figured I'd start a thread for my new DIY project, now that I'm actually building it thanks to some interest from @Lingwendil . It's a wifi enabled LED controller/driver.

I wanted my light to look more like a professional light, which meant only one cable going to the light, ideally with a connector. So that meant the board needed to take a single voltage and step it down to 12V to run a fan and 3.3/5V for the controller. This is what I came up with:

Designed to fit the spacings on the RapidLED premium heatsink, barrel connector for power, onboard DC-DC converter steps voltage down to 6.5-12V (adjustable with a pot) and then down to 3.3V for the Wemos. Has 6 drivers although with an on-board connector 8 PWM channels can be brought out for additional drivers. Each driver can accept up to 65V and the DC-DC is also rated for 60V. Output is adjustable from 350mA to 1A.

Since it's an ESP using a PCA9685 for PWM there are a couple options for code. I originally looked at the SSLAC code which is very programmable but I don't think you can view anything outside of your network and I don't think it has much for fan control or temperature reading. Then I saw O2's Blynk based controller for the LED he made, decided it looked like a good base for a project like this and started my own code.

The Blynk code is setup to have a dim sunrise/sunset mode, full daylight mode and moonlight. Each channel can be individually adjusted for each of the modes to allow warmer sunrise/sunset and whatever color moonlight. It will read the heatsink temperature from one or more DS18B20 sensors and turn a fan on when the temperature exceeds a controllable setpoint.

I've started building the first board and tested the DC-DC circuit, over the holidays I plan on finishing the board and testing it out while building my light. Starting with 2 fresh-fish and 2 crisp white COBs, this is over a 36x18x18 tank so each set of COBs basically be over an 18" cube. I'll see how it looks and may need to add more lights or may want to add some supplemental colors.

Also did up a Fritzing schematic which would let you use the code without the PCB for more DIY style:

Fritzing schematic

Blynk code is on Github here.

 

[eltila]

Thanks for the schematics

 

[Lingwendil]

Can't wait to get mine in. I guess that makes me a beta tester?

It'll be nice to have it all on one board! Perfect for the rapidLED enclosures.

 

[MrMan]

Can't wait to get mine in. I guess that makes me a beta tester?

It'll be nice to have it all on one board! Perfect for the rapidLED enclosures.

Pretty much I emailed rapid and couldn't get an extra end cap without the hole so I'm thinking maybe 3d printing an new one with the proper opening for the connector will be my best bet. Just have to learn CAD modeling now lol

Sent from my Nexus 6P using Tapatalk

 

[Lingwendil]

Pretty much I emailed rapid and couldn't get an extra end cap without the hole so I'm thinking maybe 3d printing an new one with the proper opening for the connector will be my best bet. Just have to learn CAD modeling now lol

Sent from my Nexus 6P using Tapatalk

Maybe try these guys? I used them for some audio gear a while back...

https://www.frontpanelexpress.com

 

[MrMan]

Maybe try these guys? I used them for some audio gear a while back...

https://www.frontpanelexpress.com

Might be overkill for what I need but I'll keep them in mind. Hard to tell how much it would end up being since their price options are just examples for much larger pieces.

Found this place:
https://www.elecrow.com/5pcs-acrylic-laser-cutting-service.html

Can do black plastic pieces for pretty cheap, could even get a logo engraved. Are the endcaps plastic or metal?

 

[Lingwendil]

I think its 3/32~1/8" aluminum. Easy to drill at least. They also acted like it was nigh impossible to source extra endplates when I asked too. Strange, but since everyone farms out mfg services nowadays it makes sense.


Silly question, but do you think a relocation of the barrel jack, spaced to fit through the existing hole on the endcaps could work on later revisions? If it's possible to reconfigure the PCB to work that way it could be a viable option I suppose. Otherwise its trivial to drill a hole and simply pop a plastic blockoff plug into the existing hole.

 

[Kampo]

This looks really sweet...if I had not already bought my setups I'd be all over buying one of these boards to test

 

[MrMan]

I think its 3/32~1/8" aluminum. Easy to drill at least. They also acted like it was nigh impossible to source extra endplates when I asked too. Strange, but since everyone farms out mfg services nowadays it makes sense.


Silly question, but do you think a relocation of the barrel jack, spaced to fit through the existing hole on the endcaps could work on later revisions? If it's possible to reconfigure the PCB to work that way it could be a viable option I suppose. Otherwise its trivial to drill a hole and simply pop a plastic blockoff plug into the existing hole.

If I moved the connector to the middle the DC-DC circuit would push over and the wemos would have to move. It could work, but might make the board wider which I'd like to avoid to keep as much room for LEDs as possible. Currently the board is 50mm wide which is under 2 inches.

This looks really sweet...if I had not already bought my setups I'd be all over buying one of these boards to test

Easy solution, just start another tank :wink2:

 

[Lingwendil]

If I moved the connector to the middle the DC-DC circuit would push over and the wemos would have to move. It could work, but might make the board wider which I'd like to avoid to keep as much room for LEDs as possible. Currently the board is 50mm wide which is under 2"

Understandable. I'm braindead with PCB design so I was just curious.

Easy solution, just start another tank :wink2:

I am fighting all of my instincts to not grab another 20 long to do another planted. I've got a 55 in storage that is earmarked for a freshwater build once we move in a few months, and the current 20 long reef is slated to be replaced by a 40 breeder or similar (36x18) footprint tank around the same time. Multiple tank syndrome is a hell of a drug :smile:

I think the Petco doller-per-gallon sale is coming up again soon, always a good time to grab a few 10's or 20's to play with :hihi:

 

[MrMan]

Finished building the PCB, heatsink has been shipped and should be ready to pickup on Friday.

 

[MrMan]

So I picked up my heatsink today and went to check the fit of the PCB on the slots and found they're slightly off, which is annoying since I got a drawing from them and did the PCB based on that. I should be able to drill out one edge of the holes and it'll work but shouldn't have been necessary. Also noticed that the board bows a bit when both sides are tightened so I'm going to use a thermally conductive double sided tape between the board and heatsink to ensure everything stays cool.

I'm curious though if the COBs should be installed beside each other or in front/behind eachother. I'm leaning towards this but I suppose I could always change it:

 

[Lingwendil]

:bounce:

Can't wait!

 

[MrMan]

We have light!

I don't have my proper power supply yet so I'm making do with a 50W supply I had which will let me test each LED at full brightness. They all run as expected, fan works properly, havn't tested the daily fading cycle yet but that'll be done soon. The only weird thing is that the warm white COBs are always on even when the dimming is set to 0, it's so dim you can see the individual LEDs in the COB but it's strange. They still work as expected from 1-100 though so I'm sure I can ignore it.

This is the supply I am going to use:
Meanwell GST120A48-P1M

 

[Kampo]

We have light!

I don't have my proper power supply yet so I'm making do with a 50W supply I had which will let me test each LED at full brightness. They all run as expected, fan works properly, havn't tested the daily fading cycle yet but that'll be done soon. The only weird thing is that the warm white COBs are always on even when the dimming is set to 0, it's so dim you can see the individual LEDs in the COB but it's strange. They still work as expected from 1-100 though so I'm sure I can ignore it.

This is the supply I am going to use:
Meanwell GST120A48-P1M

love that psu, makes it look even more professional. but wow 50 bucks is a lot of coin for a power brick...that said i've looked and there are not many options for 48v psus that don't look like a metal cage. i found a few chinese built ones that woudl work for my proejct in powerbrick form...but chinese powersupplies always worry me

 

[MrMan]

love that psu, makes it look even more professional. but wow 50 bucks is a lot of coin for a power brick...that said i've looked and there are not many options for 48v psus that don't look like a metal cage. i found a few chinese built ones that woudl work for my proejct in powerbrick form...but chinese powersupplies always worry me

Yea there's way cheaper to be had on ebay but they're smaller than they should be for the power rating so I feel it'll only be a matter of time until they fail. Better off buying a quality one from the get-go that'll last. I may go down to the 90W which should be enough to power the 4 COBs, but then again also nice to have some extra power if I want to add any colored LEDs.

 

[jeffkrol]

They all run as expected, fan works properly, havn't tested the daily fading cycle yet but that'll be done soon. The only weird thing is that the warm white COBs are always on even when the dimming is set to 0, it's so dim you can see the individual LEDs in the COB but it's strange. They still work as expected from 1-100 though so I'm sure I can ignore it.

This is the supply I am going to use:
Meanwell GST120A48-P1M

Check chip to heatsink for bridging..
Doesn't take much leakage voltage to light diodes..

https://www.google.com/url?sa=t&rct...45517149.pdf&usg=AOvVaw20dMqXGEKxIJ4vCE6w9uUR
BajaNomad - ghost voltage? - Powered by XMB

 

[ChrisX]

Since it's an ESP using a PCA9685 for PWM there are a couple options for code. I originally looked at the SSLAC code which is very programmable but I don't think you can view anything outside of your network and I don't think it has much for fan control or temperature reading. Then I saw O2's Blynk based controller for the LED he made, decided it looked like a good base for a project like this and started my own code.

How did you integrate the PCA9685 board into a custom PCB? Was their circuit diagram available or did you have to trace and recreate it?

Edit: Just answered my own question. The PCA9685 boards are just extensions to the chip. All you had to do was duplicate their circuit, create a new PCB layout and have it printed.

 

[MrMan]

Check chip to heatsink for bridging..
Doesn't take much leakage voltage to light diodes..

https://www.google.com/url?sa=t&rct...45517149.pdf&usg=AOvVaw20dMqXGEKxIJ4vCE6w9uUR
BajaNomad - ghost voltage? - Powered by XMB

Yea I did that right away, everything is high impedence (ie > 1Mohm) to heatsink. It's only the warm white COBs that do it, the freshfish are completely off, which is weird.

How did you integrate the PCA9685 board into a custom PCB? Was their circuit diagram available or did you have to trace and recreate it?

Edit: Just answered my own question. The PCA9685 boards are just extensions to the chip. All you had to do was duplicate their circuit, create a new PCB layout and have it printed.

Yup, just need to add the correct footprint and connections. Adafruit sells a PCA9685 breakout board as well if building this setup without the PCB.

 

[jeffkrol]

Out of curiosity did you try it off the heatsink?
Otherwise it's a driver error..
also you could try the shunt resistor thingy..

Had similar issues w/ my first puck designs (10W cheapos) and Meanwell AC/DC drivers..
Scrapped the system..