A transformer has no inherent ground connections. When forming a new system, unless the transformer is bonded to ground, the secondary system will remain ungrounded, and you may get floating voltages due to capacitive coupling to ground. The secondary winding does not have a solid connection until. Grounding is a mechanism to protect distribution equipment and people under normal operating conditions, abnormal operational (overcurrent and overvoltage) responses, and hazardous conditions such as shocks. Grounding is necessary to assure correct operation of electrical devices, to assure safety. Can the resulting system be left ungrounded with adequate protection and continue serving load? Ungrounded systems can often be avoided with proper planning and design. When this is not possible, a thorough understanding of the system behavior and the application of voltage protection schemes can. The topic of system grounding is extremely important, as it affects the susceptibility of the system to voltage transients, determines the types of loads the system can accommodate, and helps to determine the system protection requirements. The system grounding arrangement is determined by the. The secondary neutral (Wye) is left open (not grounded). Because with an ungrounded wye, the open Xo bushing can be used for ground detection, with a single PT, or voltage measurement.
