Generally, the busbar side of 10kV switchgear does not have a dedicated earthing switch. Phase-to-phase and phase-to-ground dimensions are the same because switchgear used on ungrounded or impedance grounded systems will have phase to phase voltage between the unfaulted phases and ground during a ground fault condition. It is not possible to test every configuration of bus used in. After a 10 kV ground fault, the bus VT detects no current but develops zero-sequence voltage and increased current in the open delta. Prolonged operation can damage the VT. Therefore, this paper studied the flexible grounding system consisting of. Between live parts of opposite polarity, 251-600V, Through air gap is 1", Over surface is 2". The proposed scheme successfully detects single-phase-to-ground busbar faults by using the standard settings of the wide y available overcurrent IEDs, and an IEC 61850 communication between them. It's essential for safe equipment maintenance.
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