What connector to use when using 5v 15A
TL;DR Distributing 5V is a bad idea. Use a higher voltage supply (e.g. 24V) with a local DC-DC convert for each strip.



I would highly suggest not trying to distribute 5V @ 15A at all. The voltage drop at 15A is going to be considerable unless you use very thick wire. You will struggle to find a connector with sufficient current rating that isn't excessively large and expensive.

If you think about it, if your wiring loom and connectors had a total resistance of only ~0.3 Ω, your entire voltage would be dropped across it. Even if it was only 0.1 Ω you are dropping a significant portion of your supply voltage.

Instead distribute a 24V supply. This would drop your supply current down to around 3.2A or so, which is much more reasonable. It will also be easier to find a supply capable of handling the current.

If your LED strips require 5V, then for each strip add a DC-DC convert to drop the supply down to 5V locally. By having a converter per strip, the output current for any DC-DC is lower than having just one, and the distance over which you are tranferring it is vastly reduced.