Air release valve RN III SA 24/4 03-003

Air disconnect switch – reliable protection for medium voltage lines

The RN III SA 24/4 air disconnect switch is a key element of power infrastructure, designed for the safe disconnection and grounding of circuits in overhead lines with a voltage of 24kV. The device is widely used in both distribution networks and branch points, providing effective protection and enabling safe maintenance work. The design of the disconnect switch allows for installation in both horizontal and vertical positions, increasing installation flexibility.

Construction and design features

The disconnect switch consists of three independent poles (current-carrying conductors) mounted on a common hot-dip galvanized steel beam. The distance between the poles is 430 mm. It is equipped with silicone or porcelain insulators (depending on the version), to which the main contacts made of tinned copper flats are attached. The contacts have a hinged joint, which ensures flexibility during switching and self-cleaning of the contact surface. In addition, the disconnect switch can be equipped with a grounding module, which increases its functionality. The solid construction using hot-dip galvanized steel guarantees high corrosion resistance and long-term reliability.

Application and technical parameters

The device is designed to operate in harsh atmospheric conditions. The rated disconnection voltage is 24 kV, and the rated continuous current is 400 A. The rated switching current reaches 20 A in circuits with low inductance and in ring networks. The device withstands short-circuit current up to 16 kA and peak current up to 40 kA at a rated frequency of 50 Hz. The disconnect switch meets safety and quality standards, such as PN-EN 62271-103:2011 and PN-EN 62271-102:2018 (various versions), confirmed by numerous tests and certificates. Installation is carried out by direct mounting to the pole (vertical version) or on a special supporting structure (horizontal version). Switching is performed using manual drive (optional electric), with a lever operating horizontally. It is important that the lever movement is decisive and smooth, without jerks.