EQUIPMENT FAMILY
Ring main units (RMU)
Choose a platform, then confirm the voltage, current, short-circuit rating, site conditions, cable connections and document list for the offered unit.
HJ-AM Series (Air-Insulated Metal-Enclosed RMU)
The HJ-AM Series Air-Insulated Metal-Enclosed RMU is designed for secondary medium-voltage distribution up to 24 kV. It uses ambient air as the main insulation medium, with SF6 load break switches or vacuum circuit breakers for switching. The unit offers visible fault isolation and modular flexibility.
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HJ-Eco Series (Eco-Gas Insulated RMU)
The HJ-Eco Series Eco-Gas Insulated RMU is a 12kV ring main unit that is 100% SF6-free, using dry air or N2 as insulating gas with vacuum switching. It has a GWP of less than 1, meeting strict environmental standards. Available in C, F, and V modules, it offers rated currents up to 1250A and short-circuit withstand up to 31.5kA. Suitable for utility upgrades aiming for carbon neutrality.
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HJ-GIS Series (SF6 Gas-Insulated RMU)
The HJ-GIS Series (HSRM16-12) is an SF6 gas-insulated ring main unit designed for compact secondary substations, heavy industrial networks, underground vaults, and coastal environments. All primary circuits are sealed in an IP67 stainless-steel tank, supporting long-term reliability. Available modules include load break switch, switch-fuse combo, and vacuum circuit breaker, with ratings up to 24kV and 1250A.
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HJ-RMU Series Modular Ring Main Unit (Smart Integrated Edition)
The HJ-RMU Series Modular Ring Main Unit (Smart Integrated Edition) is a factory pre-wired distribution automation platform for 12kV to 24kV networks. It integrates primary switchgear (air, SF6, solid, or eco-gas) with DTU/FTU terminals and electronic sensors, providing SCADA-ready hardware. It supports multiple communication interfaces and protocols, with IP67 internal connections and a built-in backup battery.
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HJ-SIS Series (Solid Insulated Switchgear)
The HJ-SIS Series Solid Insulated Switchgear is a ring main unit for medium-voltage distribution up to 24 kV. It uses epoxy resin solid casting, eliminating SF6 gas. All live parts are sealed and shielded, offering a maintenance-free design with zero greenhouse gas emissions. The compact footprint starts at 400 mm width.
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