Figure 4-8. If the building steel, metal water pipe, concrete-encased electrode

DOE-HDBK-1092-2004

Figure 4-8. If the building steel, metal water pipe, concrete-encased electrode, and

ground ring are available, they must be grounded and bonded to the service

equipment to create the grounding electrode system.

4.14 GROUND-FAULT PROTECTION OF EQUIPMENT

See Section 2.7 for GFCIs for personnel protection. An increased degree of protection in solidly

grounded systems can be achieved in providing ground-fault protection that will shunt trip circuit

protective devices when user-selected levels of ground fault or leakage current flow are

detected in electrical circuits. This is required to be installed on all solidly grounded wye

services of more than 150 V to ground but not exceeding 600 V phase-to-phase where the

service disconnecting means is rated at 1,000 A or more (See Figure 3-1).

4.15 PERSONNEL PROTECTIVE GROUNDS

Personnel working on or close to deenergized lines or conductors in electrical equipment should

be protected against shock hazard and flash burns that could occur if the circuit were

inadvertently reenergized. Properly installed equipotential protective grounds can aid in

lessening such hazards by providing additional protection to personnel while they service,

repair, and work on such systems. (See Section 7.5).

4.15.1 PURPOSE OF PERSONNEL PROTECTIVE GROUNDS

Personnel protective grounds are applied to deenergized circuits to provide a low-impedance

path to ground should the circuits become reenergized while personnel are working on or close

to the circuit. In addition, the personnel protective grounds provide a means of draining off static

and induced voltage from other sources while work is being performed on a circuit (Figure 4-9

illustrates an example of a personnel protective ground).

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