What is the maximum impedance difference permitted between two cans for paralleling?

The maximum impedance difference permitted between two cans for paralleling is typically set at 7.5%. This standard ensures that both energy sources operate efficiently and effectively together without causing significant imbalance in current distribution. When two cans are in parallel, a high impedance difference could lead to one can bearing more load than the other, potentially causing overheating, reduced life span, or failure of the can with the higher load. Thus, keeping this impedance difference at 7.5% allows for proper load sharing, enhancing reliability and operational stability in electrical systems.

Considerations for the other options indicate that higher limits for impedance difference could introduce significant risk and inefficiency in the operations of the system.