Flexible Design - Well-matched to a Range of Applications

Switchgear that provides some of the greatest system flexibility in the market, designed to allow freedom when configuring the lay out for cable lead-in and power/control cable terminals.

Space saving – Effective, flexible layout

The functional modular structure of the switchboard contributes ensuring an efficient layout capable of fitting easily into the installation space. The busbars are installed in two busbar sections, allowing the freedom to create a layout appropriate for the electrical room.

JP Pat No.4519067
Others, five patents in Japan four patents in four different countries (KR, DE, US, CN)

Laborsaving – Reduction of manpower

The optional condition-based maintenance (CBM) unit detects abnormalities in operating devices and other components. This helps prevent failures and realizes efficient maintenance, leading to shorter inspection times and reducing lifecycle costs. Solid insulation can be added to the busbar connectors as an option to allow future system expansion between switchgear. This option not only reduces the gas processing work, but also contributes to reduced installation work when expanding the system.
JP Pat No.4488995

Energy Saving – Reduced Operating Costs

An electro-magnetic vacuum circuit breaker (VCB) operating mechanism has been adopted, reducing operating energy by approximately 70% conventional motor-spring operating mechanisms. Optimal equipment placement and the shortest possible main-circuit conductor enables a reduction in power loss (heat value) of up to 60% by minimizing electrical resistance compared to its previous model.

High reliability – Long-term, Trouble free Operation

Electro-magnetic VCB operating mechanisms have been adopted, realizing ever higher level of reliability. The reduced number of parts*1 also translates into a lower chance of failure.
*1: HG-VA & HG-VG models have 30% fewer parts compared to our conventional motor-spring VCB operating mechanisms.

Safe Design – Ensures operator’s safety

Busbars and other main-circuit components are fitted inside strong, grounded, metal containers to secure safety. Tests have been carried out to confirm that insulation performance can withstand system voltage even if the gas pressure drops to atmospheric pressure*2.
*2: If the gas pressure drops below the gas-pressure alarm level, restore the rated gas pressure and contact a Mitsubishi Electric Co. representative.

Minimal Maintenance – Reduced Maintenance Costs

The high-tech electro-magnetic VCB operating mechanisms provide maintenance-free use for a period of over 15 years.*3 The secret to this amazingly low maintenance requirement is placing the VCB and disconnecting / earthing switch in a hermetically sealed vessel and applying an original anti-oxidation grease to the moving parts of the disconnecting / earthing switch.
*3: Under normal operating conditions as specified in IEC standards.

Environmentally friendly – SF6-free

Mitsubishi Electric Co. is a global leader in dry compressed-air insulation technologies, which has been developed through extensive experience in designing and developing SF6 switchgear. Under dry, clean and compressed conditions, air has good insulation properties, making it an ideal solution for switchgear insulation (dry-air insulation is only available for HG-VA).



Type HG-VA(dry-air) HG-VG(SF6)
Standard JEC(*1) 2350(2005)
Rated voltage(kV) 72 72/84
Rated frequency(Hz) 50/60
Rated nominal current of main busbars (A) 800/1200
Rated insulation level LIWV (kV) peak 350 350/400
Rated insulation level AC(1min) (kV) rms 140 140/160
Rated short-time withstand current (kA) 25/31.5
Rated duration of short-time current (sec) 2
Insulation medium Dry air SF6
Rated gas pressure (MPa-abs) Dry air : 0.25 SF6: 0.15
Alarm gas pressure (MPa-abs) Dry air : 0.23 SF6: 0.13
  1. *1 Japanese Electrotechnical Committee.


Type HG-VA(dry-air) HG-VG(SF6)
Standard JEC 2300(1998)
Rated voltage(kV) 72 72/84
Type of circuit breaker Vacuum
Rated short-circuit breaking current (kA) 25/31.5
Rated short-circuit making current (kA) 63/80
Break time (cycles) 3
Rated operating sequence O-1min-CO-3min-CO, CO-15sec-CO
Type of operating mechanism Electro-magnetic