Bus protection for impedance grounded systems

It is common for the electrical distribution systems in industrial facilities to be grounded through an impedance. Impedance grounded systems are either high-resistance grounded or low- resistance grounded. High-resistance grounding typically limits the ground fault current between 2A to 5A. Low-resistance grounding system typically limits the ground fault current between 200A and 500A. In either case, the goal is to limit the equipment damage caused by ground faults, while still having enough current for sensitive relays to detect and clear ground faults.