What happens on an ungrounded system during the first ground fault?

In an ungrounded electrical system, the main characteristic is that it does not have a direct connection to the earth. When the first ground fault occurs, this type of system is designed to allow the system to continue operating rather than shutting down immediately. This is an intentional design feature that helps to maintain system operation and reliability.

However, even though the system can continue to operate, a protective device is built to detect faults for safety and operational integrity. The protective device is designed to sense the fault condition and opens the circuit to isolate the faulted section. This action prevents further damage to equipment or an escalation to more dangerous situations, such as arcing or misleading ground paths.

Therefore, while the system might continue running, the protective device does indeed open upon detection of the first ground fault to ensure safety. This mechanism highlights how ungrounded systems are intended to manage faults while still maintaining functionality, albeit with conditional oversight for protection.