Gas Circuit Breakers

• 6kV, 10kV Series
• 20kV, 30kV Series

Owing to the excellent properties of SF₆ gas, these circuit breakers not only exhibit stable interrupting performance under regular short-circuiting conditions, but also under severe conditions, such as out-of-phase grounding and loss of synchronization.

The drawer-type design of the grounded tank model makes maintenance work extremely safe, and the SF₆ gas is chemically inactive and noncombustible.

When interrupting a magnetized current, the cutting-current is small; therefore, the surge at the time of interruption is less than twice the voltage applied. Additionally, restart does not occur when the charging current is interrupted, so no overcurrent is generated. Therefore, the circuit breakers can be used safely without surge absorbers for all circuits.

No need for compressors or large-capacity batteries thanks to the incorporation of an electric spring operating method. Additionally, switching operation can be performed manually at times when the power source is off.

The puffer-type arc extinguishing chamber is small and simple, and incorporating the grounded-tank design enabled a significant reduction in cubicle size.
For example, Mitsubishi Electric’s 34.5kV TGBA cubicle equipped with this circuit breaker has a footprint of only 2m² (1.2 x 1.65m) in the case of a single bus feeder board. This makes it a particularly advantageous product for use in substations, etc. located in narrow buildings.