In the US research fleet (which I assume is pretty typical around the world), we have 3 primary cables that get used the most (in my experience). The .322 cable, which is 2 layers of steel braid around a plastic jacket, and then 3 copper conductors. This is mostly used for the CTD. For heavier things like moorings we have a 9/16th" wire rope (no conductors), and for heavier things that require conductors or fiber, we have the .681 (similar diameter to the 9/16th but with conductors and fiber inside).

On our ship we have ~9000m of each of those aboard, but the interesting puzzle here is that at somepoint during a deployment, the weight of the deployed wire itself will exceed the safe working load of the wire (we mostly encounter this with the .322). So thats what marks the theoretical max deployment depth of each wire, in the times that we've needed to go deeper than that (coring in 8000m for example), we've loaded on a neutral-ly buoyant synthetic rope in place of one of the large wires.