Which grounding approach is used for minimizing voltage levels in electrical systems?

The high-impedance grounding approach is used in electrical systems primarily to minimize voltage levels during ground faults. This method connects the grounding system through a high-impedance resistor, which allows only a small amount of fault current to flow. As a result, the voltage rise on the ground faulted equipment is significantly reduced, minimizing the risk of damage to equipment and enhancing safety.

By limiting current flow during a fault condition, high-impedance grounding helps maintain system stability and allows for continued operation of equipment under certain fault conditions, which can be crucial in maintaining the supply of power or data in critical applications. This approach is particularly beneficial in systems where sensitive electronic equipment is present, as it helps to protect against overvoltages that can lead to equipment failure.

In contrast, other grounding methods have different purposes: system bonding generally focuses on ensuring a common reference point for the system; equipment grounding protects personnel and equipment from electric shock by providing a low-resistance path for fault currents; and low-impedance grounding allows for higher levels of fault currents to flow, which could potentially lead to greater equipment damage and increased safety hazards.