10 kV rural overhead line circuit
110 kV line control circuit
1100 kV SF6 circuit breaker
126 kV double-break vacuum circuit breaker
1-wire bus driving circuit
20 kV outdoor on-post vacuum circuit breaker
220 kV circuit breakers
220 kV double circuit on the same tower
24 kV outdoor high-voltage AC vacuum circuit breaker
25 Hz phase detecting track circuit
25Hz phase detecting track circuit