The chassis supports both single and dual power supplies (AC or DC). "Power supply" slot is a "port adapter" slot. 7301 power supplies are not modular (come as fixed configurations upon purchase as single or dual).
These are the paths to get to each CCX logs through CLI. They may be helpful if you are having issues accessing RTMT or downloading logs through it.
If you want to download them you have to prefix "file get " and you can add one of the options (re...