Power Injection

I watched Bill Porter’s xEssential E10 “Power Injection Made Easy” video from November 20, 2018 as well as other video’s on the topic. I was confused with one aspect and hope that you can provide clarification. I am planning to connect six 5v 75 pixel strings end to end making a 450 pixel string plugged into port 1 of a Falcon F16v3. The F16v3 will be drawing power from a Meanwell power supply providing power to the F16v3 itself as well as the pixel string. Then I plan to inject power at various points within the 450 pixel string using a 14AWG wire and a 10amp fuse at the start of the power injection run. However, this string of pixels is also receiving power directly from the F16v3 which is connected to a 5amp fuse. My understanding is that the same string of pixels should not be connected to two fuses. I am not sure how to avoid this. My only thought is that the V+ From the F16v3 to the pixel strip must not get connected and the power injection itself starts at pixel 1. Hope my question is clear. Any advise you can provide is greatly appreciated! Thank you!

You have pretty much answered your own question there Russell. You would even get away with the first pixel getting it's power from the first injection point if the first injection point wasn't too many pixels away. Being that it's a matrix and 5v I would most likely inject at the start and end in addition to the other points.

I watched that video and have set up power off my F16 and then power from the same supply via fused board to the injection point at 100 (using 5V). He has power from the board, and then power from his power injection with fuses on each too. So is that wrong having two fuses???? I'm confused.

Powering a string from 2 or more fuses creates the possibility of a 'cascade fuse failure'. That is, if something happens within the string to cause one of the fuses to open (blow) then its portion of the load is shifted to the remaining fuse(s) which then likely will cause another to open. Attempting to determine fuse failure in a string powered from multiple points is more difficult.

I have not watched the xEssentials video mentioned so cannot comment on the presentor's video content. In my opinion, I see nothing wrong with using multiple fuse powered strings if you understand and are comfortable using that particular method.