I’m building a fairly large setup using WS2812b strips and a Teensy 3 + OctoWS2811. I came across a similar post here - but there is one noticeable difference which is that although the wiring is similar, my project involves 8 entirely separate displays (of 3 strips of 60 LEDs each) rather than one big display wired into groups. My wiring diagram is attached.
I’ve come across some advice to use a single large power supply rather than smaller separate ones. This is tricky for what I have in mind as the displays may be spread out within a space - I’d like to avoid trailing power cables around (i.e. there are already wall sockets around a room). The control data I plan to run through RJ45 cables. If the distance gets too great, I’ll look at another way of sending data between the teensy and the displays. But the power makes sense to me to be more ‘localised’ to each display unit.
I’d appreciate some more eyes on what I have planned re: wiring and power, and there are a few things I’m wondering/assuming that would be good to get some thoughts on to put my mind at rest!
• Common ground - I’ve read that all strips should share a common ground. This is tricky given they are separate units with their own power supply. What’s the actual reason for this? Will I run into display problems if the power supplies don’t share a common ground (but the data cables all go to one place)?
• Power supply limit - If I’m working to the suggested max current (60mA per LED), then each of the 8 displays will draw up to 10.8A at full brightness. I’d really like to use 10A power supplies if possible. My feeling is that this will be fine if I limit brightness on the teensy/software end (I would never need them that bright), but equally I want to KNOW that the supplies are able to deliver all the current needed safely - in case there’s a glitch when data is disconnected etc.
• Fuses - should I be adding fuses anywhere in the project, other than those on the power supply plugs? Could a 10A fuse on each strip (after the power supply) ease my concerns about the max current, or would I just be repeating what’s already there?
• Power cable gauge - based on this chart I think I need at least 14AWG wire for power on each display as it won’t be carrying more than 10A, and over short distances. Would love a sanity check on that!
• Chaining strips - do I need to chain the grounds like I’m chaining the DIN/DO between strips? My understanding is that it would be redundant as the grounds don’t care which end they’re connected from.