HR20-0.5 Low-voltage Knife-fuse Switch-Knife-fuse Switch

HR20-0.5 (Type 1)

HR20-0.5 (Type 2)

Application

The HR20-0.5 low-voltage fuse-disconnect switch is a combination appliance consisting of a knife switch and a fuse. It is suitable for use in outdoor low-voltage circuits. Under normal power feeding conditions, it is used to connect and disconnect the power supply. In case of short circuit or overload, it provides circuit protection. It can be used wherever there is a transformer output to outdoor lines, such as rural power grids, agricultural and forestry farms, urban network renovation, railway petrochemical, indoor and outdoor factories of all sizes, etc.

Structural Features

The HR20-0.5 low-voltage fuse-disconnect switch adopts a three-pole common base assembly. Each pole has clip-type moving and fixed contacts, respectively fixed on the base by post insulators. The moving contact part consists of a porcelain knife handle and two mutually insulated conductive parts rigidly connected together. The user selects a suitable fuse link and connects it between these two conductive parts, serving both as a switch and a fuse. An arc-extinguishing contact is installed between the moving and fixed contacts, designed so that the arc-extinguishing contact makes contact before the main contact, preventing arc damage to the main contact. A ring-type tripping device is installed above the moving contact, allowing remote operation from the ground using an insulating hook stick. It has the advantages of simple structure, reliable performance, and convenient use. This HR20-0.5 knife-fuse switch is one of the commonly used protection devices in low-voltage distribution systems.

External and Installation Dimensions