The isolator is interlocked with circuit breaker and earthing switch. While opening the circuit, ……. opens first, then the …… and only after this …… can close.
A. isolator, circuit breaker, earthing switch
B. earthing switch, isolator, circuit breaker
C. circuit breaker, earthing switch, isolator
D. circuit breaker, isolator, earthing switch
Answer:D
The isolator is interlocked with circuit breaker and earthing switch. While opening the circuit, ……. opens first, then the …… and only after this …… can close.
A. isolator, circuit breaker, earthing switch B. earthing switch, isolator, circuit breaker C. circuit breaker, earthing switch, isolator D. circuit breaker, isolator, earthing switch