Overview
IEC TS 62271-314:2024 - High-voltage switchgear and controlgear - Part 314: Direct current disconnectors and earthing switches - is a Technical Specification by the IEC that defines requirements and type-test procedures for HVDC disconnectors and earthing switches intended for indoor and outdoor installations on transmission systems with direct voltages of 100 kV and above. It also covers their operating devices and auxiliary equipment.
Note: Disconnectors with an integral fuse are excluded from this document.
Key topics and technical requirements
The specification addresses functional, electrical and mechanical aspects needed for safe and reliable operation of HVDC switching devices. Major technical topics include:
-
Ratings and characteristics
- Rated direct voltage, insulation levels and rated continuous current
- Short‑time withstand current, rated peak withstand current and duration
- Rated auxiliary supply voltages and frequencies
-
Design and construction
- Requirements for liquids, gases and vacuum tightness
- Earthing arrangements and isolating distances
- Mechanical strength, dimensional tolerances and position indication
- Locking, nameplates and degree of protection for enclosures
-
Type tests and verification
- Dielectric tests (including wet and artificial pollution tests for outdoor insulators)
- Continuous current, short‑time and peak withstand current tests
- Capacitive current making (cable discharge) tests and classifications for earthing switches
- Mechanical and operating endurance tests, contact zone testing
- EMC tests, partial discharge, tightness, and X‑ray tests for vacuum interrupters
-
Special operational modes
- Stored energy, dependent/independent power operation and manual actuators
- Earthing switches with short‑circuit making capability and cable discharging making capability
Practical applications and who uses this standard
IEC TS 62271-314:2024 is intended for professionals involved in the design, manufacture, testing, installation and operation of high-voltage DC grid components, including:
- HVDC converter station designers and engineers
- Switchgear manufacturers and component suppliers
- Utilities and transmission system operators specifying HVDC switchgear
- Third‑party testing laboratories and certification bodies
- Procurement teams creating technical specifications for HVDC projects
Using this TS helps ensure interoperability, safety, predictable mechanical/electrical performance and compliance with internationally recognized test methods for HVDC disconnectors and earthing switches.
Related standards
While this TS focuses on DC disconnectors and earthing switches, implementers commonly reference other IEC 62271 series documents for complementary requirements (e.g., general switchgear requirements, AC switchgear sections) and standards on insulation coordination, EMC and testing methods.
Keywords: IEC TS 62271-314:2024, HVDC disconnectors, earthing switches, high-voltage direct current, type tests, short-time withstand current, cable discharge, switchgear standards.