You can replace internal power supplies as needed while the switch is operating ("hot swapping").
All installed power supplies must have the same airflow direction (front-to-back or back-to-front) and must also match the airflow direction of the fan modules.
To replace one or more AC internal power supplies in an Extreme 8820 switch, follow the steps in Install a 1600 W Internal AC Power Supply.
To replace one or more DC internal power supplies in an Extreme 8820 switch, follow the steps in Install a 1600 W Internal DC Power Supply.