nutz4lights
Full time elf
Honest question right? If voltage drop in the 5V compared to a 12V pixel string is due to the 20AWG wire, why not just ask for 18AWG wire to be used? I could see there being a challenge with soldering the larger wire down to the pad on the circuit board, but...
I already emailed Ray, but does anybody have any thoughts on the matter?
I went to an online calculator and punched in 20AWG wire, DC, 5V, 1.4A string current (what I have measured on my 50 count bullet style ws2811 strings running with white light) with a string length of around 9 meters... The calculator suggests that the voltage drop should be 0.8V so from 5.0V to 4.2V.... which would be great, but I'm seeing closer to 1.8V drop to 3.2V at pixel 50...
If I fiddle with the wire gauge setting in the calculator, I see that the the voltage drop I'm getting would make more sense for a 23AWG wire... and I believe I have ready around here that someone had counted strands and measured diameters to find that the 20AWG was not really 20AWG...
So, let's just say that the 20AWG used in the wire is really 23AWG... and we get a 1.8V drop... which requires power injection every 50 pixels for 5V applications... why not just bump up the gauge wire... I'm showing that a 16AWG wire should allow for 100 pixels of 5V with acceptable voltage drop (to 3.4V at pixel 100).
Thoughts?
-Louie
I already emailed Ray, but does anybody have any thoughts on the matter?
I went to an online calculator and punched in 20AWG wire, DC, 5V, 1.4A string current (what I have measured on my 50 count bullet style ws2811 strings running with white light) with a string length of around 9 meters... The calculator suggests that the voltage drop should be 0.8V so from 5.0V to 4.2V.... which would be great, but I'm seeing closer to 1.8V drop to 3.2V at pixel 50...
If I fiddle with the wire gauge setting in the calculator, I see that the the voltage drop I'm getting would make more sense for a 23AWG wire... and I believe I have ready around here that someone had counted strands and measured diameters to find that the 20AWG was not really 20AWG...
So, let's just say that the 20AWG used in the wire is really 23AWG... and we get a 1.8V drop... which requires power injection every 50 pixels for 5V applications... why not just bump up the gauge wire... I'm showing that a 16AWG wire should allow for 100 pixels of 5V with acceptable voltage drop (to 3.4V at pixel 100).
Thoughts?
-Louie