Description/ Specification of HV Isolator / EHV Isolator
Isolators(electrical) are switches used in electrical circuits to disconnect a circuit from source of electrical supply in offload conditions. Unlike a circuit breaker, which breaks the current in a live circuit, isolators cannot interrupt current or quench an arc that strikes due to breaking of current. Outdoor type isolators, which are used in high voltage distribution or transmission system, can be of double break or single break type. A double break isolator is having metallic current carrying part which is mounted on the central support insulator column comprising of multiple porcelain insulator disks. This is the moving contact. The two fixed contact assemblies are supported at two ends, on similar insulator mountings. The fixed contacts have clamp type multiple fingers which are under spring pressure. The central moving contact arm is rotated on it’s pivot by a motor operated and gear driven mechanism. The two ends of this moving contact arm move towards the fixed contacts at the two ends and simultaneously gets inserted in side them, thereby completing the circuit. In case of single break type the two moving contacts are mounted on two sides and meet at the center to form the contact assembly. Since the internals of circuit breakers are not visible, the complete isolation cannot be confirmed after their opening. Besides, circuit breakers themselves need to be isolated at times for periodic maintenance. For all such purpose isolators re required. This page shows catalogs of isolator manufaturers/dealers/suppliers.
HV Isolator / EHV Isolator
Isolators(electrical) are switches used in electrical circuits to disconnect a circuit from source of electrical supply in offload conditions. Unlike a circuit breaker, which breaks the current in a live circuit, isolators cannot interrupt current or quench an arc that strikes due to breaking of current. Outdoor type isolators, which are used in high voltage distribution or transmission system, can be of double break or single break type. A double break isolator is having metallic current carrying part which is mounted on the central support insulator column comprising of multiple porcelain insulator disks. This is the moving contact. The two fixed contact assemblies are supported at two ends, on similar insulator mountings. The fixed contacts have clamp type multiple fingers which are under spring pressure. The central moving contact arm is rotated on it’s pivot by a motor operated and gear driven mechanism. The two ends of this moving contact arm move towards the fixed contacts at the two ends and simultaneously gets inserted in side them, thereby completing the circuit. In case of single break type the two moving contacts are mounted on two sides and meet at the center to form the contact assembly. Since the internals of circuit breakers are not visible, the complete isolation cannot be confirmed after their opening. Besides, circuit breakers themselves need to be isolated at times for periodic maintenance. For all such purpose isolators re required. This page shows catalogs of isolator manufaturers/dealers/suppliers.
