IEC 62271-107:2019

Overview

IEC 62271-107:2019 - High-voltage switchgear and controlgear - Part 107 - specifies requirements for alternating-current fused circuit‑switchers rated above 1 kV up to and including 52 kV. Applicable to three‑pole‑operated devices for three‑phase systems at 50 Hz or 60 Hz, this third edition (2019) is a technical revision that updates test and rating rules to align with other IEC switchgear standards.

Key topics and technical requirements

• Scope and ratings
  • Applies to fused circuit‑switchers for 1–52 kV systems, three‑phase AC, 50/60 Hz.
  • Defines rated voltages, insulation levels, rated continuous current, short‑time and peak withstand currents, and auxiliary supply ratings.
• Fuse integration and current ratings
  • The term thermal current is removed; rated continuous current is now linked to installed fuse‑links. Manufacturers must list acceptable fuse‑links and the highest rated continuous current is used for tests.
• Transient recovery voltage (TRV)
  • Rated TRV is removed; TRV is treated as a test parameter, consistent with IEC 62271‑100.
• Making and breaking tests
  • Making and breaking duties are independent type tests (some may be omitted if validated as a load‑break switch). Certain test sequences (e.g., TDIt0 and TDIlow) remain linked to the same rated value.
• Function vs assembly requirements
  • Differentiation between requirements for a fused circuit‑switcher performing the function alone and when that function is part of an assembly, to avoid duplication or conflicts with assembly standards.
• Design, tests and conformity
  • Requirements cover dielectric and RIV tests, continuous current and temperature‑rise tests, short‑circuit withstand, making/breaking test procedures, mechanical operation tests, tightness, EMC, X‑radiation (vacuum interrupters), and routine tests.
• Documentation and selection
  • Guidance for type‑test reports, information to be supplied with tenders/orders, and a selection guide for rated values and applications.

Practical applications and who uses this standard

• Manufacturers of high‑voltage fused circuit‑switchers: product design, type testing, production routine tests, and technical documentation.
• Test laboratories and certification bodies: test procedures, acceptance criteria, and reporting for compliance.
• Utilities, substation designers and OEMs: equipment selection, specifying acceptable fuse‑links, system coordination, and procurement.
• Consultants and contractors: installation, commissioning, maintenance instructions, and safety/EMC considerations.
• Procurement and standards teams: creating technical specs and contracts referencing compliant switchgear.

Related standards

• IEC 62271‑1 (general rules for high‑voltage switchgear and controlgear)
• IEC 62271‑100 (AC circuit‑breakers)
• IEC 62271‑105 (switch-fuse combinations)
• Other IEC parts on assembly, testing and EMC referenced within IEC 62271‑107

IEC 62271‑107:2019 is essential for anyone involved in the specification, manufacture, testing or integration of high‑voltage fused circuit‑switchers used in transmission and distribution substations.