I am scaling up a project from a small demo to a large permanent

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I am scaling up a project from a small demo to a large permanent installation. and I am looking for advice on things that might go wrong. What should I change before the installation. I have done a bunch of smaller installations but this is my first really big one.

This system is currently working in my house.

  • 20 spokes,
  • Each spoke is 2 meters long,
  • The strips are from Adafruit WS2812 and have 60 pixels per meter.
  • Each spoke has 2x 2 meter strips of LEDs that show the same pattern. I have wired the data lines of both LED strips in each spoke together.
  • Each set of 4 spokes have a separate power supply with the grounds connected.
  • Each of the 5 power supply has a continuous rating 40 Amp at 5v (200 Watts).
  • I have 2x 15 amp 110 circuits breakers to work with on site.
  • Each pare of strips has a capacitor (1000 µF, 6.3V) across the + and – terminals
  • I am using a Teensy 3.2 https://www.pjrc.com/store/teensy32.html mostly because of memory and speed.
  • I am using a separate power supply for the Teensy
  • I am using Modbus RTU (RS485) for communication to the Teensy .
  • The data wires coming from the Teensy are in a 3 wire bundle with the power and ground.
  • The data wires are 160 cm from the Teensy to the first LED on the stips.
  • Total of 80 meters of strips, 4,800 LEDs, 200 amp at 5v for a total of 1000 W,

I do know that the Teensy produces 3.3v and the ws2812 needs 5v on the data line but it is working in my house right now. Do I need the logic level converters?

Anything else that would make this system more reliable?

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If the teensy become an issue you can always drop $3 on a arduino compatible device.

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Ws2812s are not made equal. Some work perfectly with 3.3V, some don’t. If yours are working, I would leave them alone. Alternatively, you could use the Teensy LC, I believe that provides 5V on the data line.

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@Dushyant_Ahuja The Teensy LC only has 1x 5v DI pin. I am currently using 20 different DI pins on the Teensy. one for each spoke. I thought that this would be better, as it would be faster to push out all the data simultaneously on all the pins rather then out of a single pin. Please correctly me if I am mistaken…

It also looks like the Teensy LC only has 8k of ram. ~4,800 LEDs at 3x bytes per LED will consume ~14 k of ram. I don’t think I can address all my LEDs with a Teensy LC because of the memory limitations.

I didn’t know about the Teensy LC before. Neat board, thank you for introducing it to me.

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@Dustin_Van_Tate_Test I believe that the biggest Arduino Mega has a RAM of 8k. I need at lest ~14 just to hold each pixel in ram. I don’t think an Arduino is the right choice here.

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@Steven_Smethurst I missed that. But, like I said - you should need level shifters only if your LEDs are glitching. Make sure you use something like the HCT245 series.
http://happyinmotion.com/?p=1247

I generally use them with the ESP8266 - which has the added advantage of having wifi inbuilt. Of course - it doesn’t have 20 IOs. But I think, unless you need to run 30fps animations, the ESP8266 should be able to run all the LEDs you need.

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It will change your wiring significantly but… I would go for the Teensy OCTOWS2811 adaptor (available at PJRC). For so many LEDS you will have the benefit of 8 times faster updates to your LEDS AND you get an 8 way voltage converter as a bonus !!

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Actually, that adaptor is NOT necessary at all for 8-way parallel output but it does provides 8-way level shifting from 3.3V to 5V data signals.

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@Steven_Smethurst Absolutely grab yourself a SN74HCT245N for level shifting

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Definitely use a level shifter. Any time you care about reliability, stay well within the datasheets. PJRC sells a module just for this purpose: https://www.pjrc.com/store/octo28_adaptor.html

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Not all level shifter are equal. PJRC has demonstrated big ws2811 installations and Paul really knows his stuff.

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I want to make it one to. But I want to use an octows2811 adaptor whit a teensy. Can you guys know how to modifide my FastLED code to controll 8 strip? and I want to controll whit JINX

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I would highly recommend using an octows2811 - it made things so much faster and more stable. My only regret was the wasted time having bugs, timing issues when trying to do dmx too, trying other level shifters and having issues with them etc

14

Your setup is 60pixel x 2 m x 4 strip x 5 = 2400 pixel to control (total pixel is 4800) ???

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One observation - your circuit diagram shows the grounds of all the power supplies as not connected. Please ensure that you connect the grounds of all the power supplies together.

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i definitely recommend using a level shifter to get a 5V signal. I have done an installation where the first LED is 1.75m away, and the 3.3V signal is not good enough, whereas the 5V signal is perfect.
OctoWs2811 as others have suggested is a good shout. I’ve not used it as I use APA102’s but I have only heard good things about it.