As I gain experience with the intricacies of outdoor cabling and power supply location, I will be situating several external runs of ws2811. Most will be shielded from direct view and will bounce light off an eave and soffit to produce reflected light. The setup protects cable runs and LEDs directly, but in high winds (often the case) there is some misting.
I am considering using a 16/3 extension cord cut into lengths <4 m to power and signal the LEDs, and have adopted raywu pigtails. Such conductors are robust, and easy to work with. I had used 18g 3 conductor wire, but the signal occasionally becomes flaky >3 m. I have tested the 16/3 cord and line losses are minimal up to 5 m (on the workbench). Thoughts or suggestions are welcome.
For longer runs I highly recommend you change your “mind view” about your installation.
There are two things that need to be supplied to your strip setup: Power and Data.
They have different requirements especially when dealing with longer runs.
Power is pretty well defined by Ohm’s law, you figure out the maximum current your strip will need at various distances around the setup and use wire that’s big enough so as to not add too much resistance/cause a voltage drop.
Data is completely different, it needs almost no power and is “regenerated” by every LED that gets proper data and power.
I suggest you make this distinction because your choice of 16/3 implies you’d like to run a single cable supplying power and data to your setup - the 3rd wire being the data line while the other 2 are power.
Your bench setup shows that 16AWG wire is suitable for the voltage/current/distances you anticipate and in general that’s probably a good wire choice. Power seems to be reasonably handled.
Unfortunately data is another matter, linking your data line via the “3rd” wire may work out OK in your setup, but maybe not. I’m very leery of coupling a data line alongside your power lines which is what a 16/3 cable will do. The chance for injection noise in that data stream is greatly increased, it typically shows up as sporadic flashing or flickering for no apparent reason.
You might be able to get away with it and there are a raft of resistor/mid span signal boosters/level shifters that might help. But to have a reliable long term setup, dedicate a separate wire for the data line (actually Data and Ground) and do what you have to do to make that work for you. You’ll likely need a level shifter and/or if the distance to the MCU becomes great enough a differential TxRx board pair.
I put my theory to action and was not disappointed. Voltage drop across 3 m from the Diguno to the pigtail over 16/3 extension cord was 0.14VDC, only half of the drop using 18/3 wire. There is no signal degradation. I plan to power the next run with 12V LEDs, and I expect even better performance.
Thank you for reminding me. That modification was quite successful and inexpensive. The voltage drop is negligible, I use all three conductors Line, Neutral and Ground, replacing the plug ends with Ray Wu connectors.
I used a cheap green 16 gauge 25 foot extension cord. I cut it in half obtaining two 12’ leads. I used the three conductors for Vcc, Vdat and Ground. It works well.
Both lengths were between 10 and 11 metres long straight out of the PSU and esp (i.e. no boast). ~4 straight, the rest coiled.
Wled is ‘limited’ to 9500 ma
Both ran at will white brightness, rapidly toggled between it and other modes several times. No issues. Various intricate displays. No indication of ANY issue with the data going that distance or that kind of cable.
Full disclosure when I first tried the flexible stranded cable I did have issues with the rapid toggling, suspected voltage drop. But I reseated all the connections and it was absolutely fine after that.
Obviously this is much further that I intend to travel but I wanted to understand what distance I could accomplish with a decent draw (1024 LEDs!) and no boosting or sacrificial pixels.
I have actually settled on 0.75mm2 flexible ‘pond cable’ which I have yet to test, but expect no issues.
It is worth noting that given the cost saving of solid core vs flexible (economy’s of scale I presume…) and the fact my cabling will see little movement I plan to use the twin and earth solid core as much as practical. I also believe you get less voltage drop…
Your approach to using 16/3 extension cord for your WS2811 runs sounds solid, especially considering the challenges of outdoor conditions. The thicker gauge wire should help reduce voltage drop and maintain a more stable signal over longer distances, which is crucial for digital LEDs like WS2811.
Here are a few suggestions and considerations:
Waterproof Connections: Since you mentioned misting, ensure that all connections, especially where the pigtails join the extension cord, are waterproof. Using heat shrink tubing or silicone sealant can help protect these joints.
Power Injection: If you’re running longer strips or experiencing any voltage drop, consider implementing power injection at intervals along the strip. This helps keep voltage consistent and prevents color shift or dimming.
Signal Integrity: For longer runs, you might also want to consider adding a signal amplifier or repeater if you experience any signal degradation. These can help maintain signal quality, especially if you’re pushing the limits of distance.
Shielding: If interference is a concern (e.g., from nearby electrical equipment), you might consider using shielded cable for the data line, even if the power is unshielded.
Testing in Conditions: Before finalizing everything, test your setup under the same conditions you expect in the field, particularly in windy or misty weather. This will help you identify any potential issues early.
Temperature Ratings: Make sure your extension cord and connectors are rated for the temperature extremes they may encounter outdoors.
Overall, your plan seems well thought out! Just keep an eye on those environmental factors, and you should have a reliable and visually appealing setup.
