Hi all, can anyone recommend a solid guide on approaches to wiring either 5v or 12v ws2812b strips when the start of the strip is located, say up to 5-10 meters away from the controller + power supply?
I have a couple of basic questions. Lets assume the start of my ws2812b strip is 5m away from the controller and power supply...
should capacitors and resistors be placed closer to the controller end or as close as possible to the start of the strip?
does it matter where the ground link between external power supply and controller occurs? (ie: closer to controller + power supply or at start of the strip?)
Can I split a wire from a single data pin on the controller into several lines to control multiple strips or better to just define multiple data pins (one for each strip)? (i'm planning something with 6x individual 5m strips, so if I can use one wire instead of 6, then uses less wire running all over the place).
What gauge wire is recommended for longer length DATA line? I'm good with calculations on current load for the power lines but for example, will 24 or 22 AWG suffice for 5 - 10m run of data pin line?
Basically these questions underlie 3 main design criteria which is that I want the wiring to be as simple as possible (ie: fewer wires the better), robust for outdoor use (make use of 2 or 3 way little junction boxes if necessary), and as fast as possible to set up (plug'n'play with 3 pin pig tail connectors).
Can I ask how you're powering the strips, as I have a similar project, and of course the Arduino can't power the strips, so one seems to end up with a lot of mosfets involved. Is that your experience too?
Data wire size doesn't matter. Your land-line telephone probably uses 26AWG and it works just fine. Data wires are high impedance and will pick up noise, so use twisted pair, one being a ground wire. OR use shielded wire.
wcndave:
Can I ask how you're powering the strips, as I have a similar project, and of course the Arduino can't power the strips, so one seems to end up with a lot of mosfets involved. Is that your experience too?
I'm just using an ebay el cheapo 5v/40A DC power supply. Should be able to minimise voltage drop (its not THAT far really) by using multiple 14 or 12awg DC cable runs so current load is WAY below rating. Thanks to Paul's answer I'll use those recommendations on the data wire.
Check the adafruit uber guide on powering ws2812 strips. There are various diagrams around also showing how to wire multi-strip arrays, but as far as I can tell, they all use external 5v or 12v DC power supplies.
of course the Arduino can't power the strips, so one seems to end up with a lot of mosfets involved. Is that your experience too?
No you should not need to do that.
can anyone recommend a solid guide on approaches to wiring either 5v or 12v ws2812b strips when the start of the strip is located, say up to 5-10 meters away from the controller + power supply?
At that sort of distance the capacitance of the data wire is critical. The data signal is quite high frequency and can be distorted by too much capacitance. You should use a differential buffer at each end, that is Arduino and strip.
Grumpy_Mike:
At that sort of distance the capacitance of the data wire is critical. The data signal is quite high frequency and can be distorted by too much capacitance. You should use a differential buffer at each end, that is Arduino and strip.
