Overview
IEC TS 60034-30-2:2016 - "Rotating electrical machines - Part 30-2: Efficiency classes of variable speed AC motors (IE‑code)" defines global efficiency classification for variable‑speed AC motors that are not covered by IEC 60034‑30‑1. It applies to motors designed for operation with a sinusoidal fundamental current and intended for converter operation (not direct online/grid operation). The technical specification harmonizes IE‑efficiency classes (IE1 … IE5) for motors rated roughly from 0.12 kW to 1 000 kW, voltages >50 V up to 1 kV and speeds 600 to 6 000 min‑1.
Key topics and requirements
- Scope and applicability: Includes permanent magnet synchronous machines (with/without reluctance torque), sinusoidal reluctance synchronous machines, synchronous machines with DC field windings, and induction machines designed exclusively for variable speed operation. Excludes switched‑reluctance machines, motors with mechanical commutators and motors that cannot be practically tested separately from the driven equipment.
- Efficiency classification (IE‑code): Defines nominal limits and reference values for IE1–IE5 with tables of reference efficiencies and interpolation methods for intermediate powers.
- Testing & loss determination: Uses procedures described in IEC TS 60034‑2‑3 for determination of losses at speed/load points applicable to converter‑operated motors.
- Design/environmental limits: Covers motors cooled per IEC 60034‑6 cooling codes (e.g., IC410, IC411, IC416, IC418), ambient temperature ratings between −20 °C and +60 °C (rating base 25 °C), and rated altitudes up to 4 000 m (efficiency based on up to 1 000 m).
- Documentation & marking: Specifies required information for rating plates and technical documentation (see Clause 5), and tolerances for efficiency ratings.
- Harmonization: Aligned with future IEC 61800‑9‑2 for IE‑classification of frequency converters and power drive systems; supports comparable IE coding for other drive components.
Applications and users
Who benefits from IEC TS 60034‑30‑2:
- Motor manufacturers designing and declaring converter‑rated motor efficiency
- OEMs and system integrators specifying motors for variable‑speed drives
- Energy managers and procurement teams selecting motors for efficiency and lifecycle cost optimization
- Test laboratories performing efficiency verification of converter‑operated motors
- Regulators and standards bodies aligning efficiency metrics for policy, tenders and energy labeling
Practical uses:
- Specifying IE class targets for application‑specific duty cycles
- Comparing different motor technologies (PM, synchronous, induction) on a consistent energy‑efficiency basis
- Documenting motor efficiency on rating plates and datasheets for procurement and compliance
Related standards
- IEC 60034‑30‑1 (fixed‑speed motor efficiency classes)
- IEC TS 60034‑2‑3 (testing procedures for converter‑operated motors)
- IEC 61800‑9‑2 (energy‑efficiency of power drive systems and frequency converters)
Keywords: IEC TS 60034‑30‑2:2016, IE‑code, efficiency classes, variable speed AC motors, converter‑operated motors, rotating electrical machines, permanent magnet synchronous motor, IEC 60034, IEC 61800‑9‑2.