- Jun 20, 2009
- Canberra, ACT, Australia
The total resistance indicates that they used Aluminium wire between the chinese 18 and 20 sizing. As the voltage drop you measured below shows that the wire sizing and type becomes less critical. getting these made with copper would make them even better.I get 2.6-2.7Ω (ohms) for 2x 50 pixel strings connected together. This is with the V+ and gnd of pixel 1's injection pigtail twisted together and the measurement taken between V+ and gnd at the opposite end (after 100th pixel).
That seems in line with back of the envelope calcs based on the wire resistance and per node drawAs far as voltage on 100% white, what starts at
11.91Vdrops down to
11.36Vat the end of the 100th pixel (2x strings of 50).
Thanks for the data