Summary comparison
|
method |
Features/Applications |
Representative location |
Technical logic |
|
Global Grounding |
Wide equipotential network, overall risk diversification |
large plants, power plants |
Suppressing ground potential rise and minimizing electric shock |
|
Integrated grounding |
Integrated grounding for various purpose facilities |
Buildings, hospitals, data centers |
Relieves potential difference and protects entire facility |
|
common ground |
Shared grounding between equipment, convenient for maintenance |
General factories, schools |
Reduced grounding resistance, easy management |
|
Independent grounding |
Individual grounding for each device |
Communications Bureau, Laboratory |
Blocking potential interference, localizing faults |
Global Earthing System (GES)
-
It is defined as the ‘global grounding system’ in international standards such as IEC 61936-1 and IEC 60364.
-
Requires maintenance of equipotential by configuring the entire facility as a single distribution network with a grounding network.
-
It should be designed so that the grounding resistance, contact voltage, and earth potential rise (EPR) are below the limits for human electric shock, and is recommended for large-scale facilities/industrial installations.
-
All low-voltage, high-voltage, and extra-high-voltage facilities are connected to a single grounding network.
Integrated Earthing
-
Clearly defined in IEC 60364, IEC 61936-1, etc.
-
All conductive parts, such as power, communications, and lightning protection, within a building or facility are connected to a single grounding point.
-
The purpose is to eliminate potential differences, achieve equipotential bonding, and reduce the risk of electric shock.
-
Mixed grounding methods (mixed use of individual grounding and integrated grounding) within the same electrical power usage area are prohibited.
Common/Combined Earthing
-
As specified in IEC 60364-5-54, IEC 61936-1, etc.
-
The goal is to interconnect grounding electrodes of multiple facilities, reduce grounding resistance, and facilitate maintenance.
-
Common grounding is applied when the grounding electrode of a low-voltage facility is included in the high-voltage or extra-high-voltage grounding resistance area.
-
Used in substations, factories, etc.
Separate Earthing
-
IEC 60364 describes the method of individually connecting equipment to an external earth electrode in TT and IT systems.
-
Evaluate grounding resistance for each equipment and maintain allowable contact voltage standards.
-
Separate grounding networks are required to avoid interference between sensitive devices, communication equipment, and laboratories.
Internationally, IEC standards focus on safety (grounding resistance and permissible contact voltage), equipotentiality, and minimizing potential differences between facilities, and each country's electrical installation technical standards (KSC and KEC) also reflect these standards.