At present， most substation sequential operation schemes only consider primary equipment sequential operations， and operations involving secondary systems must be implemented manually by operating personnel on the field， which will result in temporary interruption of sequential operations. Taking the implementation of an isolator at the bus side of a 220 kV circuit breaker getting hot in double bus mode for example， secondary circuits are optimized for busbars switching，isolator operation and current transformer's secondary circuit switching. The operation hours of routine operations， sequential operations before and after optimization are compared.