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1. Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 19:31:37 JST Disinformation Purveyor :verified_think:
   So after talking to a friend of mine I've decided the lamp will need active cooling if I want to keep the PSU concealed, so I'm going to add a fan. The new problem I have is regulating the fan speed based on temperature inside of the lamp stand where the electronics are. I don't really want it to run at full speed unless it's needed. I am contemplating adding a second microcontroller to read a probe and spin the fan. I have spare mcus with no network that I can probably use for this.
   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 20:00:30 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas yeah this PSU is open faced on 2 sides for passive cooling and if I do my best to conceal it I am a bit concerned it may not get enough air. I have controllers and fans to spare and adequate power to run it so other than a temperature probe I don't need anything to do it this way. I have a laptop fan which should work perfectly and is very low profile so I can have a half inch slit at top and bottom of the lamp and use the fan for exhaust at the top. I think without a temp probe I could just run the fan @ 50%, but a probe lets me turn it off completely if it isn't needed which would be ideal.
   • Niclas Hedhman (niclas@angrytoday.com)'s status on Wednesday, 15-Nov-2023 20:00:32 JST Niclas Hedhman

     in reply to

     @thatguyoverthere

     Could also lower light output to regulate temperature. Also, a modern power supply can be 90-95% efficient and cleverly placed ventilation and convection draft could be anough.

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   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 20:02:38 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas as far as lowering the light output I'd need to talk to wled to do that. I don't think wled is temperature aware so it would probably still need another controller taking those measurements. I could probably send something to home assistant if I use a network able controller but I have a few of these arduino minis that i think might fit the bill nicely.
   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 20:33:23 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas 5v leds with a total of up to nearly 30 amps for the whole thing. The problem is that 5v stuff wants 10A per meter at full power.
     
     The strips I'm using are also fairly high pixel density. I used them for my desk lamp last year and you end up with about twice as many leds as you do with the 12v strips I have.
   • Niclas Hedhman (niclas@angrytoday.com)'s status on Wednesday, 15-Nov-2023 20:33:24 JST Niclas Hedhman

     in reply to

     @thatguyoverthere How much power are you going to output from the PSU?

     Say driving 50Watts of LED current, you shouldn't get more than 5W of heat from PSU, and that should cool passively, especially if you have a reasonable heat sink.

   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 20:33:51 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas
   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 20:37:24 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas Each shelf has a strip that will run the length of the front edge with the top shelf being slightly longer than the ones below. All in all I am using around 3 meters of leds at this density (just under which leaves room for the mcu[s] and fan). Like I said though I'm not sure I'll ever need to bring the leds to 100%. I just think adding a fan to help keep the psu cool if I do isn't going to do too much to the design except allow for smaller ventilation holes
   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 20:49:10 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas I have a few different fans but the one I'm thinking of using is 5v and ultra low profile because it's a laptop fan and I think it's exhaust orientation is perfect for this application (small 1/2" slit in the back of the lamp shoud suffice). The dislike of fans is why I want to use pwm and an extra controller to only turn it on when necessary. My office ambient temps vary with the seasons because it's a sun porch with not the best insulation (lots of old windows) so if temps are good now they might now be in August. I could even go so far as including an emergency shutoff with the second MCU if I run the switch through it and allow temperature to turn off the relay if the fan is at 100 and it is still too high or something.
     
     I'm planning on making the back serviceable so I may be able to make some changes in the future if necessary but I'd like to work out a good electronics plan before I settle on the dimensions of the lamp.
   • Niclas Hedhman (niclas@angrytoday.com)'s status on Wednesday, 15-Nov-2023 20:49:11 JST Niclas Hedhman

     in reply to

     @thatguyoverthere

     Also, some fans can move a lot of air at relatively low speeds, so if fan is required, look for large diameter and probably a high end brand like Noctua.
     I love it when people build stuff.
     Good Luck.

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   • Niclas Hedhman (niclas@angrytoday.com)'s status on Wednesday, 15-Nov-2023 20:49:14 JST Niclas Hedhman

     in reply to

     @thatguyoverthere

     Alright, Before deciding on the active cooling, I would test the PSU with full load and see whether the temperatures are excessive.
     I hate fans, and sometimes it is "better" to compromise on the "delivery", say less current or multiple PSUs.

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   • Niclas Hedhman (niclas@angrytoday.com)'s status on Wednesday, 15-Nov-2023 21:03:05 JST Niclas Hedhman

     in reply to

     @thatguyoverthere

     Most PSUs have overheating protection built-in, so I wouldn't spend time on that. If it doesn't, I would suggest you get another PSU.

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   • Disinformation Purveyor :verified_think: (thatguyoverthere@shitposter.club)'s status on Wednesday, 15-Nov-2023 21:15:00 JST Disinformation Purveyor :verified_think:

     in reply to

     • Niclas Hedhman
     @niclas yeah kind of just thinking out loud. I am planning on adding a switch to the mix, and wled only has room for one switch IIRC, so if I were to want to interrupt from any other controller I'd probably want to run the switch through that controller, but you are right that it shouldn't be necessary. The fan may not either as you pointed out. I just don't mind taking the time to consider ways I can help prevent failure before I build it out.
     
     I have been playing around with a few design ideas. I'm not much of an artist but I may try and draft something out in openscad later. I kind of have it in my head, but a model would help get everything laid out. That said I modeled out the book case I was going to build in openscad and then followed none of those plans (happier with the final anyway).