Are all of the equipment and structures in a substation connected to a grounding grid?

• A. False
• B. True
• C. Sometimes
• D. Not Applicable

Answer: (B)

All equipment and structures in a substation are bonded to the grounding grid to create a common, low-impedance path to earth. The grounding grid is a network of buried conductors that ties together transformers, switchgear, bus supports, racks, and other metal structures, as well as safety-related items like fences. This bonding ensures fault currents have a direct route to earth and keeps exposed surfaces at or near earth potential. That setup helps protective devices operate quickly and keeps touch/step voltages within safe limits for personnel. Because of this purpose, the statement that all equipment and structures are connected to the grounding grid is the best answer.