What Is Metal-Enclosed Switchgear?

Metal-enclosed switchgear is an assembly that integrates power reception and distribution equipment—such as circuit breakers, measuring instruments, busbars, and control devices—within a grounded metal enclosure. Due to its structure, which completely covers all live parts, this equipment provides exceptional safety and reliability by preventing accidental electric shocks and inhibiting the spread of fire. Consequently, it is widely utilized as core infrastructure in large-scale buildings and industrial plants.

Transition to the New Standard (JIS C 62271-200)

The JEM 1425 standard, which has been widely applied in Japan, will be withdrawn in March 2025 and fully transitioned to the JIS standard harmonized with international standards.
With this transition, the safety concept will shift from "Classification by partition structures" to a functional classification based on "Loss of Service Continuity (LSC)" during maintenance and inspection, which more closely reflects actual operational practices. This enables more advanced system design, such as clarifying the scope of power outages in the event of failure or during inspections.

We offer a product lineup compliant with the new standard "JIS C 62271-200."
Currently, we provide products that conform to Loss of Service Continuity (LSC) category "LSC1" and Partition Class "PI" (equivalent to the former JEM 1425 CW/PW types). We propose power reception and transformation equipment that ensures the same level of safety and operability as before, even under the new standard.

*April 2026: Evaluation and certification acquired for Public Building Electrical Equipment and Materials.

Harnessing switchboards used to receive electricity supplied by an electric power company, these units are applied to high-voltage (6.6 kV) power-receiving systems with installed power-receiving capacity of up to 4,000 kVA. Everything from main shutoff devices to step-down transformers and breakers for distribution lines are housed in metal boxes.

The unit is referred to as a CB model where the main shutoff device is a high-voltage AC circuit breaker and as a PF/S model where the unit does not include a protection relay or other such component thanks to the use of a fuse-switch combination for installed power-receiving capacity of up to 300 kVA. Structurally speaking, we also offer cubicles for outdoor or indoor environments as well as thin-style cubicles to match the attributes of the installation site. Certified cubicles designed to secure a reliable source of emergency power to be supplied to firefighting systems and other such equipment are also available.

Control panels are devices primarily used to operate, protect, and monitor electric motors (air-conditioning equipment, fans, and pumps) and other such equipment. For this purpose, they house circuit breakers, switches, protection relays, and other such components.

There are control panels for use outdoors or indoors depending on the location site and wall-hung or free-standing control panels according to size. We also offer certified control panels for disaster-prevention systems.

Distribution boards distribute electricity diverted from a main line to electric light fixtures (lighting and outlets) and motor circuits. In order to protect these circuits, these boards house molded-case circuit breakers, switches, and other such components. In addition, distribution boards are also used to perform lighting control for illumination and operational control for small electric motors.

There are wall-hung or free-standing distribution boards according to size as well as shaft-type boards for which doors are not required due to their being installed inside pipe shafts. We also offer certified distribution boards for disaster-prevention purposes.

PDUs (power distribution units) are a type of highly functional and reliable distribution board used to receive electricity supplied by UPS (uninterruptible power supply) units and distribute it to IT equipment (network devices and servers) and other essential services. They are used together with PDPs (power distribution panels) (PDFs) designed to supply electricity to subdivided loads.

In the Japanese market, electrical facilities for key industries such as data centers and semiconductor factories are increasingly requiring the adoption of products compliant with international standards, including IEC standards. This trend is driven by the recent shift toward larger-scale and higher-load operations, as well as the expansion of investment by foreign-capital enterprises.

To address these market conditions, we have entered into a partner license agreement with ABB for the "System pro E power" switchboard, which complies with the "IEC 61439-1/-2" standards. new.abb.com

Through this agreement, we will integrate ABB’s world-class, high-quality IEC switchboard technology with our extensive experience in design, manufacturing, and operation cultivated for the domestic construction market, industrial facilities, and data centers. This synergy enables us to provide domestically produced IEC switchboards that meet the specific requirements of the Japanese market.

These switchboards constitute a type of metal-enclosed switchgear used in large plants and wind-turbine generator systems for the distribution of 24 kV of electricity. An air insulation system has been adopted out of consideration for the environment.

In solar power generation systems, interconnected boards are used to connect with the power networks of electric power companies. Voltmeters and protection relays required for interconnection and transformers for voltage matching are mounted onto these boards. Connection boxes used to connect power conditioner units to solar cell panels are also available.

When constructing a UPS system, an input transformer panel will be needed to step-down the voltage of supplied commercial power where high-voltage AC inputting is used. I/O boards used when building a system to provide parallel redundancy or a common spare for a UPS system and output branch power boards for securing branch circuits matched to loads are available.

Easy-access switchgear panels, telephone terminal boards, low-current terminal boards, grounding terminal boards, apparatus storage boards, protection relay boards, instrument boards, control boards, outlet boards, alarm panels, main controllers, and other boards and panels.