ZW20-12 Outdoor Vacuum Circuit Breaker

The ZW20-12 is an outdoor AC vacuum “boundary circuit breaker” — a multifunctional intelligent device combining four switch functions in one unit: vacuum breaker, vacuum load switch, recloser, and sectionalizer. The main configuration consists of a vacuum breaker, a CH-40 intelligent controller, and an external voltage transformer (bilateral PT available for ring-network distribution automation lines).

Widely used in 10 kV / 13 kV urban and rural power grid spatial ring networks as a disconnecting switch, contact switch, or automatic switching device for ring-network load transfer, it also serves as a boundary switch (“watchdog”) on branch lines, and as a recloser or sectionalizer on overhead feeder distribution networks. With remote management, protection and control functions, and communication capability, the ZW20-12 uses mA-level zero-sequence and phase-to-phase short-circuit current detection to automatically isolate single-phase grounding faults and phase-to-phase short-circuit faults.