Ratings and Specifications

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

Superior Interruption Performance

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.

High Level of Safety

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

Low Surge

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.

Easy to Handle

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.

Compact, Lightweight, Simple Structure

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.

Ratings and Specifications

<6kV, 10kV Series>
Type 6-SFG-40 6-SFG-63 10-SFG-40 10-SFG-50
Rated voltage 3.6/7.2kV 7.2kV 12kV
Rated nominal current 1,200A
2,000A
3,000A
4,000A
1,200A
2,000A
3,000A
4,000A
1,200A
2,000A
3,000A
4,000A
1,200A
2,000A
3,000A
4,000A
Rated frequency 50/60Hz
Rated breaking current 40kA 63kA 40kA 50kA
Rated breaking time 5 cycle
Rated gas pressure (at 20 ℃) 0.5MPa
Supply command pressure (at 20 ℃) 0.45MPa
Locking pressure (at 20 ℃) 0.4MPa
Compliant standards JEC-2300
<20kV, 30kV Series>
Type 20-SFG-25A 20-SFG-40A 30-SFG-25A 30-SFG-40A
Rated voltage 24kV 36kV
Rated nominal current 600A
1,200A
2,000A
3,000A
1,200A
2,000A
3,000A
600A
1,200A
2,000A
3,000A
1,200A
2,000A
3,000A
Rated frequency 50/60Hz
Rated breaking current 25kA 40kA 25kA 40kA
Rated breaking time 5 cycle
Rated gas pressure (at 20 ℃) 0.5MPa
Supply command pressure (at 20 ℃) 0.45MPa
Locking pressure (at 20 ℃) 0.4MPa
Compliant standards JEC-2300