IEC 61587-2:2011

Overview

IEC 61587-2:2011 is an international standard published by the International Electrotechnical Commission (IEC) that specifies seismic testing requirements for mechanical structures of electronic equipment cabinets and racks. This standard applies to the mechanical structures conforming to IEC 60917 and IEC 60297 series and focuses exclusively on their ability to withstand seismic events. It does not cover the electronic components installed inside nor cabinets or racks featuring anti-seismic isolation systems.

The key purpose of IEC 61587-2:2011 is to define consistent test conditions, including specimen setup, loading schemes, and seismic excitations (single-axis or tri-axis acceleration), to evaluate the structural integrity of cabinets and racks exposed to earthquakes. This second edition advances testing methodologies by introducing tri-axial excitation to better simulate real earthquake conditions, offering more accurate assessments compared to the previous single-axis focus.

Key Topics

• Scope and Application
  Applies to mechanical structures of cabinets and racks as per IEC 60917 and IEC 60297. Excludes electronic systems and anti-seismic isolation structures.
• Test Specimen Setup
  Cabinets/racks are loaded with dummy plug-in units distributed through their height, replicating realistic installation conditions. Physical dimensions (height, width, depth) and load distribution are standardized for testing.
• Seismic Test Methods
  • Single-Axis Acceleration: Traditional method involving vibration along one axis.
  • Tri-Axial Acceleration: Introduced in Edition 2.0 for simultaneous vibration along three axes, simulating actual seismic wave randomness.
• Required Response Spectra (RRS)
  Specifies seismic wave acceleration spectra with defined damping ratios (typically 2% or 3%), used as reference for generating test vibrations for single or tri-axial testing.
• Assessment Criteria
  Post-test evaluation of structural performance to confirm whether the cabinet or rack withstands prescribed seismic intensities without unacceptable damage or failure.
• Exclusions
  Does not cover seismic testing of internal electronic devices or systems, nor structures with built-in seismic isolation devices.

Applications

IEC 61587-2:2011 is essential for manufacturers, test laboratories, and engineers involved in the design, certification, and validation of electronic equipment enclosures intended for seismic zones. Practical applications include:

• Assessing reliability and safety of 19-inch racks and modular cabinets used in telecommunications, data centers, industrial electronics, and control systems under earthquake loading conditions.
• Supporting compliance verification and conformity assessment processes for electronic equipment mechanical structures.
• Guiding the design of rugged and seismic-resistant enclosures to minimize operational disruptions and equipment damage during seismic events.
• Providing a benchmark for structural testing under standardized seismic waveforms, including both simplified single-axis and more representative tri-axial excitations.
• Enabling customized testing scenarios by adjusting cabinet size, load distribution, and seismic intensity to meet specific project requirements beyond the reference setup.

Related Standards

• IEC 60917 Series: Modular mechanical structures for electronic equipment-standardizes dimensions and design requirements for plug-in units and subracks.
• IEC 60297 Series: Specifies mechanical dimensions, particularly the 19-inch rack series for electronic equipment enclosures.
• IEC 60068 Environmental Testing Series: Including parts covering vibration tests-IEC 60068-2-6 (sinusoidal vibration), IEC 60068-2-47 (specimen mounting), IEC 60068-2-57 (time-history vibration)-which provide methodology references for seismic test execution.
• IEC 60068-3-3: Provides guidance on seismic testing methods specifically for equipment, supporting the understanding and application of IEC 61587-2.

By adhering to IEC 61587-2:2011, stakeholders ensure that the mechanical structures of cabinets and racks used in seismic-prone areas are validated against rigorous testing protocols, enhancing safety, reliability, and operational continuity of critical electronic systems during earthquakes. This standard is vital for achieving international harmonization in seismic testing practices for electronic equipment housings.