IEC 60068-3-3:2019

Overview

IEC 60068-3-3:2019 - Environmental testing - Part 3-3: Supporting documentation and guidance - Seismic test methods for equipment is the 2nd edition (2019) of the IEC guidance for seismic dynamic testing. It applies primarily to electro‑technical equipment (and can be extended to other equipment and components) and is focused on verification based entirely on dynamic testing (analysis or combined test/analysis approaches are outside its scope). The 2019 revision aligns test levels with seismic activity, provides a standard shape for a required response spectrum for uncertain seismic environments, and updates terminology (replacing “envelope” with the mathematically precise term “dominance”). The corrigendum of September 2021 is included.

Key topics and requirements

• Seismic classification: Defines general seismic class and specific seismic class and guidance for selecting between them.
• Test wave types: Specifies multifrequency/time‑history tests and single‑frequency methods (sine‑beat, sine‑sweep, continuous sine), plus other waveforms for simulation.
• Vibration response investigation (VRI): Procedures to identify critical frequencies and modal response before qualification testing.
• Single and multi‑axis testing: Guidance on single‑axis, biaxial and triaxial installations and sequencing.
• Calculated amplitude test method: Methodology for the general seismic class, including selection of test acceleration, wave factor, geometric factor, damping ratio, duration and safety margins.
• Required response spectrum: A standard response spectrum shape is given for general seismic class applications where seismic environment is unknown or imprecise.
• Conditioning and mounting: Requirements for mounting, functional monitoring during tests, measurement practices and conditioning for assemblies, equipment and components.
• Terminology and documentation: Clauses on service conditions, malfunction and qualification criteria, and detailed test documentation.

Practical applications

• Use for seismic qualification of electrical cabinets, switchgear, control systems, power electronics, telecommunication racks and industrial equipment intended for seismically active locations.
• Supports test labs, manufacturers, design and qualification engineers in preparing test plans, specifying vibration levels and documenting compliance.
• Helps procurement and certification bodies define objective, reproducible seismic test requirements tied to regional seismic activity.

Who should use this standard

• Environmental and vibration test laboratories
• Product qualification and reliability engineers
• Manufacturers of electro‑technical and industrial equipment
• Specifiers, procurement and regulatory compliance teams evaluating seismic ruggedness

Related standards

• IEC 60068 series (environmental testing) - see in particular IEC 60068-2-57 (referenced response spectrum guidance).

Keywords: IEC 60068-3-3:2019, seismic test methods, environmental testing, vibration testing, seismic qualification, response spectrum, electro‑technical equipment.