1. If the vacuum circuit breaker trolley within the high-voltage switchgear is closed while in the test position, the trolley breaker cannot be moved into the working position. (Prevents closing under load.)
2. If the grounding switch within the high-voltage switchgear is in the closed position, the trolley breaker cannot be closed. (Prevents closing with the grounding switch engaged.)
3. When the vacuum circuit breaker within the high-voltage switchgear is closed and in operation, the rear door of the cabinet is mechanically interlocked with the grounding switch mechanism. (Prevents accidental entry into an energized compartment.)
4. When the vacuum circuit breaker within the high-voltage switchgear is closed and in operation, the grounding switch cannot be engaged. (Prevents applying the grounding switch to an energized circuit.)
5. When the vacuum circuit breaker within the high-voltage switchgear is closed and in operation, the trolley breaker cannot be withdrawn from the working position. (Prevents disconnecting the breaker under load.)
