What could happen if a protection device is not capable of interrupting current at the available fault values?

If a protection device is not capable of interrupting current at the available fault values, it could potentially experience catastrophic failure, such as an explosion, while attempting to clear the fault. This occurs because the device might not be designed to handle the high levels of energy associated with a fault condition. Under such circumstances, excessive current can lead to overheating and arcing within the device.

Additionally, when a protection device fails to interrupt a fault as intended, it may fail to protect the downstream equipment and circuits, leading to further damage. The rapid rise in temperature due to excess current can create conditions where components may melt or even vaporize, posing significant safety risks, including the risk of the device rupturing or exploding. Therefore, the importance of ensuring that protection devices are rated appropriately for the fault currents they may encounter cannot be overstated, as this is crucial for maintaining both system integrity and safety.