The 21-year-old has yet to make a first-team appearance for the Eagles, but has had six separate loan spells.
In total, he has made 32 league appearances for clubs including Port Vale, Yeovil and Gillingham.
The centre-back has also appeared for England at Under-21 level and joins a club which has won just one of their opening five League One games.
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League One side Southend United have signed defender Ryan Inniss on a season-long loan from Crystal Palace.