G+_Kenny Gardner Posted September 15, 2017 Share Posted September 15, 2017 Neopixel Clock. Ok, somebody please proove me wrong. I cut the Power Jack off the recommended Power Supply to solder on new connectors. There is no way to get 5 amps through those tiny little wires. It takes a minimum of 16 gauge to pump 5 amps through the wires. Link to comment Share on other sites More sharing options...
G+_Kevin Britain Posted September 15, 2017 Share Posted September 15, 2017 5amps? no i believe that should be 5 volts.. Link to comment Share on other sites More sharing options...
G+_Kenny Gardner Posted September 15, 2017 Author Share Posted September 15, 2017 Don't trust it. The wire sizes on the UBEC's are also incredible small. I'm going to play it safe and use 5V supplies from Adafruit and Jameco. I'll be using a Photon without the RTC (that's what the Internet is for), and the UBEC's. Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted September 16, 2017 Share Posted September 16, 2017 Kenny Gardner you are correct that a 16AWG pair is best for 5A, it will only warm by 10°C in still air. If the PS has 22AWG wire it will warm 35°C with 5A applied, not enough to cause a problem but enough that you shouldn't bury the cable in a wall. Ref. page 4 of: belden.com - www.belden.com/docs/files/upload/22Technical_Information.pdf Link to comment Share on other sites More sharing options...
G+_Kenny Gardner Posted September 16, 2017 Author Share Posted September 16, 2017 I'm getting ready to do a load test on the 12V supplies and the UBEC's. Don't trust them. I believe this project uses a total of 86 LED's? At worst case (60ma) that's 5.1 amps. My 5V supplies are capable of handling that, should worst case ever happen. Link to comment Share on other sites More sharing options...
G+_Jim Hofmann Posted September 16, 2017 Share Posted September 16, 2017 I wondered about that. A couple thoughts. The brick (if UL Listed) must safely handle the rated power delivered, so whatever wire size they are using must be OK. So then the question is, why does it work? I have noted that the bricks use stranded wire (which I thought was to prevent a single wire break due to flexing would cause a failure). When I used the site above for multiple stands 10 x 26 awg is equivlent to 16 which was OK for 5 amp. Just my thoughts. Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted September 16, 2017 Share Posted September 16, 2017 Jim Hofmann True, if it is actually UL listed and not just a Chinese made device with marking but not actually tested, sadly too common, then it is safe to use for it's intended application. You are far more likely to get a unit that actually was type tested when bought from Adafruit or Jameco, etc. then from one of the direct from China exporters. Also true that stranding is to give wire better flexibility and endurance to flexing. 10 x 26AWG stranded wire, assuming you can buy that configuration, would almost certainly be called 16AWG stranded wire. A couple of the normally available configurations are 18AWG = 10x28, 16AWG = 7x24. However I suspect Kenny Gardner is seeing something like 7x30 (22AWG) lead wires on the unit he bought. It's actually hard to determine the actual stranding/total AWG without counting and measuring the individual strands with a good measuring caliper or a micrometer. Link to comment Share on other sites More sharing options...
G+_John Sullivan Posted September 16, 2017 Share Posted September 16, 2017 Kenny Gardner: getting back to your original question, what project are you looking at please? This one uses 60 LEDs with a 18ma current draw each (total of slightly more than 1 amp) adafruit.com - NeoPixel 1/4 60 Ring - 5050 RGB LED w/ Integrated Drivers Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted September 16, 2017 Share Posted September 16, 2017 cosmic Ray Here's the page with Padre's rough calculations and the links to the power supply parts. twit.tv - Know How... 333 LED Clock Build Part 4 | TWiT.TV Link to comment Share on other sites More sharing options...
G+_John Sullivan Posted September 17, 2017 Share Posted September 17, 2017 Paul Hutchinson: yes, thanks, I knew about that, but Kenny Gardner's original message mentioned "NeoPixel clock" so I wasn't sure if he was looking at Padre's project or something else. When I Google for NeoPixel clock, it is just the outer ring of 60 LEDs. Again, just wanted to be sure we were talking about the same project. Link to comment Share on other sites More sharing options...
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