Ring Main Unit (RMU) Panels 

Specification
A Ring Main Unit (RMU) is a compact, sealed, and maintenance-free switchgear unit used in medium voltage (MV) power distribution networks. RMUs are designed for automatic power distribution, fault isolation, and supply restoration, making them an ideal choice for industrial plants, urban power distribution, and utility substations.

Working & Operation

• Normal Operation: RMU distributes power through a ring network, ensuring redundancy and reliability.

• Fault Detection & Isolation: If a fault occurs, the faulty section is automatically isolated, while power continues to flow through alternative routes.

• Load Switching: RMU allows safe and efficient switching operations without disrupting power supply.

• Restoration & Monitoring: Modern RMUs are equipped with remote monitoring and automation features for rapid fault resolution.

Salient Features 

• Voltage Rating: 11kV to 36kV

• Current Rating: Up to 630A

• Breaking Capacity: Up to 25kA

• Insulation Type: SF6 gas-insulated or air-insulated

• Compact & Modular Design: Requires minimal space, ideal for urban installations

• Automatic Load Transfer: Ensures continuous power supply with minimal downtime

• Maintenance-Free: Sealed enclosure prevents contamination and external damage

• IP Rating: IP54 / IP55 for outdoor installations

• Smart Grid Ready: Can be integrated with SCADA and remote control systems

Applications

• Power Distribution for Urban & Industrial Networks

Types 

Gas-Insulated RMU (SF6 RMU)

• Uses SF6 gas as insulation, ensuring superior protection and longevity.

• Compact and sealed, making it maintenance-free.

• Widely used in industrial power distribution and urban networks.

Air-Insulated RMU (AIS RMU)

• Uses air as an insulating medium, making it environmentally friendly.

• Slightly larger than SF6 RMU but cost-effective.

• Used in industrial plants and substations.

Motorized & SCADA-Enabled RMU

• Equipped with motorized mechanisms for remote operation.

• Can be integrated with SCADA systems for real-time monitoring and automation.

• Used in smart grids, metro stations, and high-demand power networks.

Outdoor & Indoor RMU

• Outdoor RMU: Weatherproof, designed for harsh environmental conditions.

• Indoor RMU: Installed within buildings, substations, and control rooms.