Air-Insulated Ring Main Units

Reliable Secondary Switchgear Solutions Ring main units (RNBs) are compact, fully enclosed, factory-prefabricated cabinets designed for medium-voltage (MV) power distribution. These switchgear are easy to replace, require minimal maintenance, and provide a high level of protection. To meet diverse needs, RNBs are available in a variety of voltage options, making them suitable for both indoor and outdoor applications. Our product portfolio includes air-insulated, gas-insulated, and oil-insulated RNBs, all compliant with international power distribution standards. Our latest air-insulated models use synthetic air, eliminating the need for sulfur hexafluoride (SF₆), offering a range of specifications to address specific requirements. Our RNBs are specifically developed for medium-voltage power distribution networks, suitable for both indoor and outdoor installations, and operate stably even in the most demanding environments. They offer significant environmental benefits without compromising functionality. Whether you are upgrading existing infrastructure or deploying new secondary switchgear, TOONICE’s RNBs ensure efficient, sustainable, and future-proof power distribution.