For a PowerStore 5200T system with a mixed SSD and SCM (Storage Class Memory) drive combination, the following statements are correct:

Expansion Enclosures are supported: PowerStore 5200T supports expansion enclosures, allowing for the addition of more drives to increase storage capacity and performance. This flexibility is crucial for scaling the storage system to meet growing data requirements.

SCM drives do not add to usable capacity: SCM drives in the PowerStore 5200T are primarily used for caching purposes rather than for adding to the system's usable capacity. These drives improve performance by accelerating data access times but do not contribute directly to the overall storage capacity.

Dell Technologies PowerStore 5200T Documentation

Dell Entry-Level and Mid-Range Storage Community