I'm designing a system that provides power/ethernet/serial for up to 5 daisychained units. All of the boxes will be metal and my initial plan is to run power and signal ground through the 14 pin cables that will connect each unit. Each cable's shield will be tied to chassis ground and the plan is to tie chassis and power ground together in the PSU/COMM box.
My question is A) is this a sound idea and B) should I connect an RC connection (1Meg/100pF or something) from my PCB mounting holes to the chassis ground in each box? Pros/Cons?
The boxes will draw between 5 and 10 amps at 48V. We'll have 100 Mbit ethernet and also rs232.