I´d like to install more (USB) power in my case - semi-separate from the PSU feeding my modules.
Would it be as simple as using a larger power brick, then Y split power cable inside, feeding internal PSU + a DC step down converter on the same 15V line?
Could add thicker cables.
Many options to step down 15V to 5v, from Alibaba stuff to the pro gear:
Cosel STMGFS 30W Isolated DC-DC Voltage in 18 → 76 V dc, Voltage out 5V dc 6A
Heat will not be a problem, can make a 6-8hp heat sink + ventilation grid.
Just need power to iPad Pro and other suchness. Have a Doepfer A-183-9 4 USB power lying around.
But as the Marathon Man was asked: Is it safe?