Vacuum and air circuit breakers for MV and LV protection. VS1, ZN85, DW45, CM1 series for reliable fault interruption.
A circuit breaker is an automatic electrical switch designed to protect electrical circuits from damage caused by overcurrent or short circuit. Unlike a fuse, a circuit breaker can be reset to resume normal operation after tripping. Medium voltage circuit breakers use vacuum interrupters (VS1, ZN85) or SF6 gas for arc extinction. Vacuum interrupters are preferred for environmental reasons and lower maintenance. Low voltage circuit breakers include air circuit breakers (ACB) for high currents and moulded case circuit breakers (MCCB) for distribution feeders. Ziyao Power supplies VS1 indoor vacuum circuit breaker (12kV), ZN85 outdoor vacuum circuit breaker, DW45 air circuit breaker (630-3200A), and CM1/NM1 moulded case circuit breaker series.
Where circuit breakers are used in real-world power infrastructure projects.
Circuit breakers for 12-40.5kV switchgear panels and substations.
Main incomers and feeders in low voltage switchgear.
Circuit breakers for motor starting and protection.
Generator circuit breakers for power plants.
Explore our range of circuit breakers for various voltage levels and applications.
Real-world installations using our circuit breakers.
Technical guides and resources about circuit breakers.
Vacuum circuit breakers use vacuum interrupters for arc extinction, SF6 breakers use sulfur hexafluoride gas. Vacuum is environmentally friendly with no greenhouse gas, lower maintenance, and longer life. SF6 has higher interrupting capacity for very high fault currents but faces increasing regulation due to its high global warming potential.
Use Air Circuit Breakers (ACB) for main incomers and high-current feeders above 800A where high interrupting capacity and drawout construction are needed. Use Moulded Case Circuit Breakers (MCCB) for distribution feeders up to 800A where compact size and lower cost are priorities.