IEC 62271-106:2021

Overview

IEC 62271-106:2021 is the international standard for high-voltage AC contactors, contactor-based controllers and motor-starters. Edition 2.0 (2021) replaces the 2011 edition and aligns numbering with IEC 62271-1:2017. The standard applies to indoor equipment for systems above 1 kV and up to 24 kV at frequencies up to 60 Hz, and includes additional requirements for outdoor installations when equipment is housed in a protective enclosure. It covers three-pole devices for three-phase systems and single-pole devices for single-phase systems, and addresses controllers where contactors are combined with short‑circuit protective devices (SCPD).

Key topics and requirements

• Scope and exclusions: Defines applicable device types (contactors, starters, contactor-based controllers) and exclusions (circuit‑breaker-based starters, semiconductor contactors, certain liquid or speed-control starters).
• Ratings and characteristics: Requirements for voltage, current, utilization categories and rated making/breaking capacities.
• Design and construction: Mechanical, dielectric and enclosure protection requirements for indoor and sheltered outdoor installations.
• Type tests and routine tests: Procedures to verify making/breaking performance, short‑time current withstand, TRV (transient recovery voltage) characteristics, endurance and on-load operating cycles.
• Service conditions and environmental influence: Normal/special service conditions, pollution exposure and weatherproofing tests for outdoor use.
• Selection, documentation and labelling: Guidance on specifying contactors and motor‑starters, information to be given with enquiries/tenders and manufacturer documentation.
• Safety and EMC: Requirements and informative guidance on safety, control/auxiliary components and electromagnetic compatibility aspects.

Practical applications and users

Who uses IEC 62271-106:

• Manufacturers of high‑voltage AC contactors and contactor-based motor-starters
• Utility and industrial electrical engineers specifying switchgear for medium‑ and high‑voltage motor installations
• Procurement teams and consultants preparing tenders and technical specifications
• Test laboratories and certification bodies performing type tests and routine tests
• Designers of metal‑enclosed switchgear where contactors interface with SCPDs

How it’s used:

• Selecting contactors/motor‑starters for motors in 1–24 kV systems
• Ensuring compliance with required making/breaking and short‑time current performance
• Defining test regimes for type approval and factory testing
• Specifying enclosure protection and environmental tests for outdoor installations

Related standards

• IEC 62271-1:2017 (general requirements for high‑voltage switchgear and controlgear)
• IEC 60060-1 (high‑voltage test techniques)
• IEC 60255-149 (thermal electrical relays) - referenced in the standard
• IEC 60282-1 / IEC 60644 (high‑voltage fuses) and other IEC 62271 series parts for complementary equipment

IEC 62271-106 is essential for anyone involved in the design, manufacture, testing or procurement of high-voltage switchgear components used to switch and protect motors in medium- and high‑voltage power systems.