Common redundancy configurations used in refrigeration systems include N+1, 2N, and 2(N-1) configurations. N+1 redundancy involves duplicating critical components, such as compressors or pumps, to ensure that the system remains operational even if one component fails. 2N redundancy involves duplicating entire systems, providing 100% redundancy and ensuring continuous operation even in the event of a complete system failure. 2(N-1) redundancy involves duplicating critical components and providing spare capacity to handle partial system failures. The choice of redundancy configuration depends on the system’s criticality, availability requirements, and cost constraints.