The switchgear tripped because the busbar insulation layer broke down, causing a ground fault that triggered protective action tripping. 1 Accident Overview On March 17, 2023, a photovoltaic. Busbar protection (BBP): Protection intended to detect and operate to clear faults on a busbar. The CT Trouble function in the B30 and B90 relays detects this condition by using a low-set differential element, typically set around 10% of the least heavily loaded circuit connected to the bus, that asserts after a settable time delay. The CT Trouble alarm can be sent via SCADA to operating. In the event of a major disturbance on the system that caused an under frequency event, the relays would trip the main 140 kV breaker feeding the mine. If the mine owned relay was the only one to trip, the mine could go back online in stages. Due to the fact that the short-circuit levels of bus bars.
